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How to Use Graduated Neutral Density Filters for Landscape Photography

03 Jan

The post How to Use Graduated Neutral Density Filters for Landscape Photography appeared first on Digital Photography School. It was authored by Francesco Gola.

graduated neutral density filters landscape photography

If you want to create stunning landscape photos without significant post-processing, then you need a graduated neutral density filter.

But why are GND filters so important? What do they do? And how do you use them?

That’s what this article is all about.

So if you’re ready to discover how you can capture beautiful landscape images with GND filters, let’s get started!

Dynamic range

Since the camera was invented, we have tried to copy one of the greatest wonders of our body: the human eye. Unfortunately, while it’s been nearly 200 years since we first captured light with the camera, we are still far from overcoming Mother Nature.

Why?

Because the eye sees much better than the camera.

The parameter that describes this behavior is called dynamic range. It basically defines the difference between the minimum and maximum value of brightness that a device (like your eye or the sensor of your camera) is able to record. From a practical perspective, dynamic range defines the ability of your camera to see details in very dark areas and very bright areas of a scene.

If you’re wondering how much more your eye sees compared to your camera, the answer is staggering. Your eye can see about twice as much dynamic range as older cameras (though camera technology has come a long way in recent years!).

The problem

Thanks to the eye’s massive dynamic range, when you look at a marvelous sunset, you’re able to see all the details in the scene (in both the sky and the land).

But as soon as you try to capture the scene with your camera, you’ll get an overexposed sky or an underexposed foreground. The dynamic range of your camera is limited, and can therefore capture detail in only one of these areas, so you have to choose.

Given that limitation, how can we hope to shoot a beautiful sunset or a wonderful sunrise and capture all the marvelous details, both in the sky and on the land?

There are different methods to overcome this problem, but my favorite is the use of graduated neutral density filters (also known as GNDs).

What is a graduated neutral density filter?

A graduated neutral density filter is a piece of glass made up of two distinct parts:

A completely transparent area, and a darker section.

Now, by positioning the darkest part of the filter to correspond with the brightest portion of the scene you’re photographing, you can reduce the exposure difference (dynamic range) in the frame.

In other words, by positioning the dark part of a graduated neutral density filter over a bright sky, you can reduce the difference in brightness between the sky and the land for a much more even exposure.

To reduce the exposure difference is to reduce the dynamic range of the scene – so your camera can simultaneously capture detail in both bright and dark areas of the scene. GND filters are like sunglasses for your camera – except that the sunglasses are only applied to a portion of the image, rather than the entire shot.

Types of graduated neutral density filters

Graduated neutral density filters are typically distinguished by the type of transition between the transparent and dark areas of the filter. There are three main families of GNDs:

Hard-edge filters are characterized by a clear boundary between the transparent and dark areas. You use a hard-edge GND when the separation between the bright and dark areas of your scene is very defined, such as when photographing a seascape with a flat horizon.
Soft-edge filters are characterized by a soft transition (they change from light to dark more gradually), and are therefore used when the transition between light and dark areas is less distinct. A classic example is a mountainous scene, where the mountains intersect with the sky.
Reverse filters are nothing more than hard-edge GNDs with a dark area that fades away as you move from the line of separation to the upper border of the filter (so the filter is darker in the middle than on the edge). Reverse GNDs were invented to better manage sunrises and sunsets, where the light is more intense on the horizon line (in the middle of the scene). If you love seascapes (like me!), this filter will be your best friend forever.

Another difference between filters is the material. Higher-quality filters are made of optical glass. Putting an inexpensive resin filter in front of a lens worth hundreds (or thousands) of dollars is not a great idea.

Finally, GND filters are distinguished by their ability to block light. In other words, how dark are they at their most extreme?

In landscape photography, you generally need one to four stops of darkness during sunrise and sunset, depending on the weather conditions. This is the reason why most filters on the market offer these gradations.

You can shop for graduated neutral density filters on Amazon or at B&H Photo Video (they ship worldwide).

How to use a GND filter in the field

Using graduated neutral density filters in the field is very simple.

First, try to take exposure readings off the darkest and brightest areas of the scene (usually the foreground and the sky, respectively). The difference in exposure will indicate the intensity of the filter you’ll need.

For instance, if the meter reading for the sky is 1/250s and the meter reading for the foreground is 1/30s, then the difference between those readings is three stops (1/250s > 1/125s > 1/60s > 1/30s), so to balance the exposure you should use a 0.9 (3-stop) GND.

At this point, just mount the filter with its dark side over the brightest part of the scene. This is why a GND screw-in filter doesn’t make sense. You would not be able to align the transition area with the scene, whereas a drop-in filter lets you position the transition area perfectly.

To avoid holding the filter with your hands, you can buy a filter holder. Once the holder is mounted in front of your lens, it will hold your filters in place. (Note that you can stack multiple filters this way.)

There are many nice holders on the market, but the best one (in my opinion) is the V6 Holder by NiSi filters. It’s the only filter holder that lets you simultaneously install three different filters and a polarizer without any vignetting issues (plus, it works as wide as 16mm on full-frame cameras).

Graduated neutral density filters in landscape photography: Conclusion

Without graduated neutral density filters, capturing sunrise and sunset scenes will be hard – and sometimes impossible.

That’s why I recommend you always have at least one GND in your bag.

And the limited dynamic range of your camera will just be a bad memory!

The post How to Use Graduated Neutral Density Filters for Landscape Photography appeared first on Digital Photography School. It was authored by Francesco Gola.

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Samsung details new 65/14nm stacked sensor design for improving power efficiency, density of mobile image sensors

08 Oct

Stacked Architecture of the chipset Samsung details in its new paper.

Samsung has published a paper detailing a new stacked CMOS mobile image sensor that uses a 14nm processing layer to deliver high-resolution images while reducing power consumption.

The stacked sensor consists of two chips: a 12MP backside-illuminated (BSI) pixel chip on the top that uses 65nm process and a bottom chip for analog and logic circuits that uses 14nm process. By using the super-fine 14nm process on the processing layer, Samsung says it could achieve a 29% drop in power consumption compared to current conventional sensors that use a 65nm/28nm process.

Microphotograph of Implemented Sensor (Left: Top Chip & Right: Bottom Chip)

Samsung says the chip is capable of outputting at 120 frames per second while consuming just 612mW of power. The analog and digital power supply requirements also drop to 2.2V and 0.8V, respectively, compared to conventional 65nm/28nm process chipsets.

What this all translates to is a more energy-efficient stacked sensor for future smartphones that also manages to improve data throughput and reduce noise. It also paves the way for creating sensors with smaller pixel pitches, maximizing the potential for even higher-resolution sensors without increasing the size of mobile sensors. As illustrated in the below graphic, a 16MP sensor with a 1.0um pixel pitch is the same size as a 13MP sensor with a 1.12um pixel pitch.

Of course, smaller pixels means each pixel will be less sensitive, but Samsung emphasizes this shortcoming can be overcome through its pixel-merging technologies such as its Tetracell (2×2) and Nonacell (3×3) technologies, which will merge data from neighboring pixels together to achieve better image quality when light is scarce.

Specifications of the 12MP sensor Samsung details in its paper.

Samsung specifically notes the power-saving nature of stacked sensors using the 65nm/14nm process will be ‘critical’ for 8K video capture and even higher-resolution sensors, as power consumption is one of the biggest factors limiting 8K capture on current smartphones.

As tends to be the case with developments of this kind, there’s no knowing when we might see this 65nm/14nm stacked sensor design inside a consumer smartphone.

Articles: Digital Photography Review (dpreview.com)

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Firecrest 77mm 16-Stop Stackable Neutral Density Filter Review

26 Aug

The post Firecrest 77mm 16-Stop Stackable Neutral Density Filter Review appeared first on Digital Photography School. It was authored by John McIntire.

There is something about long exposure photography that is just, for lack of a better word, appealing. Blurring moving elements (like water, clouds, tourists and moving cars) in your images can create an ethereal or even surreal aesthetic that many photographers, myself included, are drawn to. Formatt-Hitech’s Firecrest 16-stop neutral density filters take long exposure photography to the extreme. By allowing ten-minute exposures in the middle of the day, these filters open up long exposure techniques to normally impossible times. And it does it with fantastic results. In this article, I’ll review the Firecrest 77mm 16-stop Stackable Neutral Density Filter.

What is it?

Firecrest-77mm-16-Stop-Stackable-Neutral-Density-Filter

A neutral density filter is a piece of material (glass or resin in most cases) that you affix to the front of your lens. What they do is cut down the amount of light hitting your sensor, increasing the amount of time you need to expose for. Doing this allows you to get longer exposures than you would normally be able to, making it easy to blur water and clouds in a satisfying way.

Most ND filters come in a range of one to three stops. However, five and ten-stop filters are also very popular amongst landscape photographers. During golden hour and blue hour, when light levels are generally quite low, these strengths of filter make it easy to achieve exposures that last for several seconds.

Image: An exposure time of 408 seconds in the middle of the day is impossible without a specialist f...

An exposure time of 408 seconds in the middle of the day is impossible without a specialist filter such as this one.

What a 16-stop filter allows is extremely long exposures even in the brightest of lighting conditions; including midday sun. For example, with a 16-stop filter, an exposure of 1/2000th of a second becomes 30 seconds. In comparison, with a 10-stop filter, that 1/2000th of second exposure becomes 1/2 of a second. You can probably already see the advantage that the denser 16-stop filter provides.

To drive it home, look at the sunny 16 rule, which says that on a bright sunny day, an exposure of f/16 at 1/125th of a second should give you close to a correct exposure (it usually does). With a 10-stop filter, that becomes 8 seconds.

That might be good enough in many cases, but it also won’t completely blur anything other than the fastest moving elements. With 16 stops, that 1/125th of a second becomes 8 minutes and 44 seconds, ensuring anything moving in your frame is either blurred or disappeared.

What is this good for?

Firecrest-77mm-16-Stop-Stackable-Neutral-Density-Filter

A 16-stop ND filter allows you to blur moving objects in your frame, which can lead to more pleasing images.

Being able to blur details out of clouds and water allows you to remove details that might detract from your subject. This lends itself well to minimalist styles of photography. If that fits your taste, the results can be stunning.

Exposures of this length not only blur moving elements within your frame but can also completely remove other moving things. Boats in rivers, tourists in front of landmarks, and anything else that might move through your frame during the exposure time disappears.

A filter of this strength is also good for things like star trails at night.

Before you consider

Image: You may need some extra specialist equipment before you get started, such as the trigger that...

You may need some extra specialist equipment before you get started, such as the trigger that allows the control of your camera with a phone.

The one thing that you need to know before you consider purchasing a filter like this is that you will need some extra equipment you may not already have. A high-quality tripod is an absolute must as you will need to keep your camera absolutely still during the long exposures.

The other thing you need to take into account is some way of controlling your camera. Because many cameras are limited to exposures of 30 seconds, you will need a way to keep the shutter open in bulb mode for the duration of the exposure without touching the camera. There are many options out there, including remotes and cable releases. I used the Pulse time-lapse trigger from Alpine Labs, which lets you control your camera with your phone. There are others available too, like the MIOPS trigger.

An exposure calculator is also an absolute must as you will need to be able to calculate how long your exposures need to be. There are plenty of free options available for both Android and iOS.

The Filter

Firecrest-77mm-16-Stop-Stackable-Neutral-Density-Filter

After shopping around for a bit, I decided on Formatt-Hitech’s circular screw-in Firecrest 77mm 16-Stop stackable neutral density filter. This filter has a few features that make it stand out.

Since I knew that I would not be using any other filters in conjunction with this one, I wanted a circular screw-in variety. That’s because I thought that the length of the exposures might create the opportunity for light leaks with my normal filter system. I might be wrong on this, but it’s not a chance I wanted to take.

Formatt-Hitech claims their filter is truly neutral (including in the UV and infrared spectrums) and that there are no color casts. This is important to me as my Lee Big Stopper (10-stops) always adds a strong blue cast that is painful to deal with. I won’t go into details about the coatings as you can find them on the product listings.

Does it do the job?

Image: The Formatt-Hitech Firecrest 77mm 16-Stop stackable neutral density filter is certainly a cap...

The Formatt-Hitech Firecrest 77mm 16-Stop stackable neutral density filter is certainly a capable piece of kit.

That’s an emphatic “yes” from me. While there are some downsides to the filter, it provides all of the quality you could expect. The few places it does fall short are all easy to overcome and well worth the little effort to do so.

Pros

Exposure times

The exposure difference between a 10-stop and 16-stop filter can be a bit staggering at first.

Just as the exposure calculator said, the 16-stops of ND filter provides really long exposures even in daylight. 1/125th of a second becomes nearly nine minutes, while 1/15th of a second becomes nearly one hour and thirteen minutes.

Attaches well

It still takes care, but the filter attaches easily enough.

It’s easy enough to attach the filter to the filter thread of your lens. It does require care as it is easy to slip (I’m sure that’s more me than the filter), but with this technique, there’s no reason to go fast anyway.

Color casts

The color represented without the 16-stop filter.

Color represented with the 16-stop filter.

I won’t say there is no color cast, but they are very minimal if they appear. Comparing shots with and without the filter side by side, it does seem that there is a slight, slight shift towards blue and green. However, I am not sure if that’s an optical illusion. Either way, it’s easy to deal with.

Cons

There are some downsides of both the filter and the technique. However, their effects are minimal and easy to overcome.

Extra equipment

Firecrest-77mm-16-Stop-Stackable-Neutral-Density-Filter

As mentioned, to get started with this technique, it’s not just the cost of the filter you need to take into account. If you don’t have a good enough tripod or some variety of release to trigger your camera, you will have to shell out for those.

Light leaks

Circled is a pair of light leaks that appear at either edge of the frame.

Despite opting for the circular filter to avoid light leaks, they did appear in my images at the left and right of the bottom third of the frame. They were minimal and easy to deal with in post-production, but they are there.

I have done some research, and it seems there’s a chance these leaks are coming from where the lens attaches to the camera body. If that’s the case, you can fix it by covering the join with black material. Formatt-Hitech also sells an accessory that fits around the front of the lens and filter to help prevent light leaks.

Exposure times in low light

When it comes to shooting later in the day when the exposure times get longer, and the light changes rapidly, it’s likely your required exposure time will change partway through your exposure. For example, if your metered exposure when you start is 1/125th (8 minutes and 44 seconds), and the light levels drop to 1/30th (if the sun moves behind a cloud for example) during that exposure, the new time is 36 minutes and 24 seconds. This means that your image will be quite underexposed.

Because of this, I’ve found this technique works better in the middle of the day when light levels are consistent.

Noise and hot pixels

Here, you can see a combination of noise and hot pixels after an 8-minute and 44-second exposure.

Noise and hot pixels have little to do with the filter itself. Extremely long exposures with digital cameras open you up to problems with noise. The longer your shutter is open, the more noise appears in your frame.

Software is very good at dealing with this, but you do need to be aware of it.

This is especially true if you opt to up your ISO in lower light levels to keep the exposure time in the minutes rather than in the hours.

Direct light

Taken in overcast conditions, the technique has emphasized the flatness of the light.

In direct sunshine, contrasty conditions get emphasized.

What I’ve found with this technique is that it works best with direct light on your subject. If the conditions are overcast, or the light is otherwise dull, the long exposure tends to emphasize the flatness of the scene.

Of course, that won’t always be the case and please don’t take that as a rule of any sort, it’s just an observation. If you live somewhere that is sunny and bright most of the time, this won’t pose you much of a problem. However, I live in Yorkshire and overcast days are the rule rather than the exception.

Price

I do not include the price of the Firecrest 77mm 16-Stop Stackable Neutral Density Filter as either a pro or a con. At $ 125, it’s probably not going to be an impulse buy for most photographers. However, for what it is, what it does, and how well-made it is, it is well worth that price. It’s also roughly the same price as filter offerings from companies like Lee Filters.

Overall experience

Overall, the Formatt-Hitech Firecrest 77mm 16-Stop Stackable Neutral Density Filter does exactly the job I bought it for.

In the end, the Firecrest 77mm 16-stop Stackable Neutral Density Filter does exactly what I wanted it to when I bought it, and it does it well. The complications aren’t hard to overcome, and it is well worth the extra effort. At $ 125, it is well within reach of anyone who wants to have a serious attempt with the techniques it offers.

I also found that I really appreciate the side effects of the technique. Because the exposure times are incredibly long, you can spend a couple of hours on location and come away with only a handful of images. This slow-treacle approach to photography is enjoyable and turns the whole experience into a mindful one.

If you like the effect of streaky clouds and flat water, or you are into minimalist photography, this type of filter may be indispensable for you.

Do you do long exposure photography? Do you use a 16-stop filter? What are your experiences? Share with us in the comments!

The post Firecrest 77mm 16-Stop Stackable Neutral Density Filter Review appeared first on Digital Photography School. It was authored by John McIntire.

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Try this DIY Neutral Density Filter for Long Exposure Photos

15 May

The post Try this DIY Neutral Density Filter for Long Exposure Photos appeared first on Digital Photography School. It was authored by Rick Ohnsman.

You could buy an expensive ND filter to make a long exposure image like this. Or, you could do it “on the cheap” with the trick you’ll learn in this article. 162 seconds f/8, ISO 100

You’ve seen those landscape photos where the water has been rendered silky smooth, ocean waves look more like fog, or the clouds have streaked motion effects? How are they done? They are long exposure photos. The shutter speed often measured in full seconds rather than fractions of a second. Some even measured in minutes of exposure. In low light, you can sometimes slow your shutter speed by decreasing the aperture size and setting the ISO as low as it can go.

Of course, if you’re working in bright light, you may find that even with the smallest aperture and lowest ISO you still can’t get the shutter speed slow enough to produce the effect you want while still maintaining proper exposure. What can you do then? It’s time for a Neutral Density Filter.

So what are they, how do they work, and how can you achieve a similar effect without immediately laying down about $ 100 U.S dollars for one? Read on my friend.

This one was done with a variable ND filter. With a 30-second exposure, whatever moves will blur. Note the water and clouds.

What is ND and why use it?

On a bright sunny day, you may reach for a pair of sunglasses to reduce the amount of light coming into our eyes. A Neutral Density (ND) Filter is much the same for your camera. The “density” part of that term refers to how dense or dark the filter might be. The “neutral” portion of the term refers to the coloration the filter might add to the image.

If we’re making color images, we’d like a filter that would help reduce the amount of light while remaining neutral in color and not putting a color cast on our images. So we want a neutral filter that can cut the light in situations where the ambient light is too bright to get a slow shutter speed beyond that obtainable with a combination of the lowest ISO and smallest aperture.

A 6-stop ND filter was used here. 30 seconds, f/20 ISO 100

Types of ND filters

The DIY approach to long exposure photography to be discussed here uses a method never initially designed for photography but will allow you to give this technique a try “on the cheap.” Rather than spend around $ 100, it’ll cost you a tenth of that. Before I reveal the “secret,” let’s first talk about the commercial photographic ND filters you might buy.

Camera filters typically fall into two types:

Screw mount – Those that screw into the filter threads on the front of your lens

Square filters – Those that are mounted to the lens with a filter holder.

Both are available in varying degrees of density. How dark the filter is, is typically described in how many “stops” of light it reduces compared to an exposure without the filter.

For example, if you made a proper exposure at ISO 100, f/5.6, 125 seconds, and then after the filter was mounted, you needed to slow the shutter speed to 1/2 second to get the same exposure, (assuming you left the ISO at 100 and f-stop at 5.6), that filter would be a 6-stop ND filter. (1/125 – > 1/60 -> 1/30 – 1/15 -> 1/8 -> 1/4 -> 1/2 second ). The density of the filter would have reduced the amount of light by 6-stops.

You can purchase both screw mount and square filters in various “strengths” or number of stops they reduce the light.

For example, this 77mm screw-mount 6-stop ND filter made by B&W runs about US$ 71, while this popular 10-stop square mount ND filter, the Lee “Big Stopper” is at this writing US$ 129.00.

A variable ND might work, but take it too far…

…and you’ll get weird artifacts.

Variable ND Filters – Another type of ND filter uses two polarized filters mounted together so they can be rotated in a way that produces variable density. One might think this is a better solution than a fixed ND filter, allowing the photographer the means of adjusting the desired stops of reduction.

That would be ideal, and it works – to a point.

The problem with variable ND filters is sometimes they can produce nasty “artifacts” that spoil the image, especially on wide-angle lenses at higher density settings with less expensive variable ND filters.

More expensive variable ND filters will be better, but of course, cost even more.

The “One Weird Trick” ND filter

You’ve seen that “one weird trick” phrase used on the web before, right? Usually, it’s for a gimmick that is less than a quality product. I confess, what I’m going to suggest here is a bit of a gimmick and no, won’t deliver the results of the pricier dedicated photography ND filters. You have to perform a few workarounds to get it to produce decent results and mounting it to your camera will be a little… “funky,” shall we say? The upside is, it will probably cost about 1/10th of what a true photographic ND filter.

So, it could be a nice introduction to long exposure photography, while allowing you to explore this technique on a budget to see if it’s for you.

So here’s the big reveal…

What you are going to use is a piece of welder’s helmet glass.

You’ve seen welders wearing helmets while they work and perhaps noted a glass “window” they look through to observe their work? The intensity of arc welding is so great that without a way to darken the welding spark the welder would be blinded. So, a piece of very dark glass, a “density filter,” is what they have in their helmets. The common denominator is the welder wants to darken the welding arc and you, as a photographer, want to darken the light coming into your lens.

These aren’t spacemen. They are welders and that piece of glass you see in their helmets is what you need for this “weird trick.”

What and where to get it

What you are looking for is a piece of welding glass used in a helmet. Pieces can be purchased alone, (as replacements for the helmets) and in various sizes and “grades.” You might have a local welding supply shop where you can get these or purchase them online. Here is a link to an example. The glass measures 4.5″ x 5.25′ (114.3 mm x 133.35 mm) which is large enough to cover most camera lenses. It comes in grades 4, 5, 6, 8, 10, 11, 12, and 14 with the higher numbers being darker/denser.

This chart may help you in determining the conversion from “grade” to the amount of f-stop reduction:

To keep it simple, most often you will use a 6-stop or a 10-stop ND filter. One popular brand of ND filters is Lee. Their “Little Stopper” is a 6-stop filter, and their “Big Stopper” is a 10-stop filter. So consulting the chart, if you wanted a 6-stop welding glass filter, get a Grade 6, and for a 10-stop reduction, get a Grade 8.

The left half of this shot shows how the uncorrected image looks due to the heavy green color of the welder’s glass. The right has been white-balanced using the custom white balance method discussed.

Density Yes, Neutral… not even close

This is probably the biggest drawback to using a piece of welding glass as an ND filter. You can get very dark pieces of welding glass, so density isn’t a problem. The problem is that most welding filters have a very pronounced green, or in some cases, gold color cast.

Dedicated photography ND filters may have a little coloration, but try to come as close to neutral as possible. You will pay more for more neutral filters as you’d prefer to get darkening without coloration. So what to do when using a welding glass filter?

Three options to dealing with the color cast

There are three things you can do to help reduce the distinct coloration a welding glass filter causes:

Shoot in Raw, (which you do anyway, right?) and adjust your white balance when editing to compensate.
Set an in-camera Custom White Balance
Plan to make your images monochrome where color casts won’t be a problem.

Let’s discuss these options.

The first is simple enough. Yes, when you review your images after shooting on the camera LCD they will look very green. (I’ve only used the green welder’s glass, not the gold). Just know you will be adding lots of magenta, (the opposite of green), to your white balance when you edit. Even then, good color may be a struggle.

Rather than fight the color cast, maybe monochrome is the ticket when using the welder’s glass ND trick.

The second option, setting a custom white balance, is a good idea. To do so, mount your welding glass filter, (more on that in a minute) and make an exposure of the sun or bright sky. Then, using the custom white balance function of your camera, (consult your manual on how to do this), store that image and white balance on it, creating a custom white balance you can use to shoot with when using your welding glass filter.

The advantage of this is image playback on your LCD will be closer to a normal color.

Additional tweaking will likely be needed in post-processing, but this may help you a bit when shooting.

The third option, (and to me maybe the best) is not to fight the color cast and plan to make your welding glass filter shots monochrome. Long exposure images have an “ethereal” look often enhanced in a monochrome image. So, rather than fight trying to restore good color from that alien green image, embrace monochrome.

If you decide you love long exposure photography, you will then likely buy a photographic ND filter which will make much better color shots.

Calculating your exposure

Before mounting your welding glass on your lens, you will want to compose your shot as usual. You will also want to obtain good focus. Do this first, because you won’t be able to see much of anything with the welding glass mounted.

Once focus has been obtained, switch the focus to manual. Consider putting a piece of tape on the focus ring so it won’t move later.

Now make a shot with good exposure without the filter. You will be changing your shutter speed once the filter is mounted, so choose an aperture and ISO. What setting you choose will depend on the depth of field you require and also how long you’d like your exposure to be. The slower the shutter speed you set here (while still getting a proper exposure), the longer your exposure can be with the filter.

Your subject will largely dictate your desired exposure length and the look you are trying to achieve. A silky waterfall might only require a 2-second exposure while smoothing ocean waves could take 30 seconds and streaking clouds in the sky a couple of minutes. There is no formula here – trial and error will help you learn what works right.

The monochrome version of this shot above was done with the welders’ glass and an exposure time of 1.6 sec. This shot was taken later when the last rays of sun lit the turbines and also used 1.6 seconds. Too short a shutter speed and the blades were frozen. Too long and they disappeared. 1.6 seconds was the “sweet spot.”

Using an app to calculate shutter speed with the filter

Your meter will likely be useless once you mount the welding glass ND filter so you will need to calculate shutter speed yourself using the previous exposure information as a starting point. There are numerous smartphone apps available to help you. I like the one made by Lee Filters (Android / iOS ). Made for use with their Little (6-stop)/Big (10-stop)/Super (15-Stop) filters, you will need to tweak a bit when using it with your welding glass. However, it will get you in the ballpark, and you can adjust from there.

Let’s use an example: You’ve made a shot without the filter and with the ISO set at 100 and the aperture at f/22 you can get the shutter speed down to 1/15th of a second and make a proper exposure. You bought both a Grade 6 (6.67-stops) and Grade 8 (10-stops) pieces of welding glass. What will your new shutter speed need to be with each filter installed? Using the Lee app, we can see the 6-stop reduction would put us at between 4 and 8 seconds and the 10-stop reduction at 1 minute.

Again, plan on using these adjusted settings as starting points. Try them and adjust your shutter speed (or possibly other settings) as needed. Definitely plan on taking multiple shots as you get things dialed in. Long exposure photography is not something you do in a hurry.

It’s funky, but it works. Reverse the lens hood and use rubber bands to attach the welder’s glass filter.

Attaching the welding glass filter

You’ve set up the camera, composed, focused, locked everything in, calculated your new shutter speed and are ready to mount the welding glass ND filter. I think I used the word “funky” earlier in the article to describe how you will attach your DIY ND filter to your lens. The photo here, showing how reversing the lens hood on your lens and then using rubber bands pretty much depicts the technique.

Something to improve it a bit – put some black gaffer tape on the edges of your piece of welders glass. This will give the rubber bands a surface with more friction to grab onto. (It also helps you in hanging onto the glass). I’m not sure if the edges of the glass would transmit light onto the image, but the tape will also prevent that should it occur. If your lens doesn’t have a hood to reverse, try larger bands which will allow you to stretch them back around the camera body.

Try not to disturb the focus ring as you mount the filter. You will not be able to check focus again once the filter is in place.

Set your focus BEFORE mounting the filter and turn the switch to Manual focus (MF)

Making the shot

With the welder’s glass filter mounted, you will pretty much be “flying blind.” You will not be able to see anything through the viewfinder, and maybe, if your filter isn’t too dark, you might be able to see just a little bit using live view if your camera supports that. You better have composed and focused before mounting the filter as you can’t see to do it now. Your meter will also not work with such low light.

While you could use the 2-second timer to trip the shot, I’d suggest a remote release. You will also definitely need one if you’ll be making exposures over 30-seconds (on most cameras) in which case you will be putting your camera in Bulb-Mode.

A release that allows you to lock the shutter open during the exposure will help a lot here. The Lee exposure calculator app also has a countdown timer. Activate it when you open the shutter and it will countdown and beep at the end of the calculated exposure time telling you when to close the shutter.

If your shutter speed will exceed 30-seconds, you will probably need to use bulb mode. A remote release is a good idea in such cases.

You may also want to consider using the noise reduction feature of your camera. Noise can be a problem with long exposures. The noise reduction feature will make a second black frame image the same length as your first shot and then subtract any random noise or hot pixels from your image using the black frame as a reference.

Keep in mind, however, that the black frame exposure will be as long as the original shot so if you are, for example, making a 2-minute exposure, your camera will be busy for four minutes. I told you, you don’t do long-exposure photography in a hurry.

No filter. A straight shot – 1/25 sec. f/8 ISO 100

Back in post-production

You edit your long exposure images much as you do with any regular shot with the big exception of that crazy color cast. There are lots of web resources that tell you how to help correct for that cast so I won’t spend time on that here. Just know that with this welding glass technique you will never get the color as good as you would without the filter. I still believe that monochrome is the way to go here.

Using the welder’s glass ND. Custom white balanced in the camera, color corrected again in Lightroom and Photoshop. 162 seconds, f/8 ISO 100. The monochrome version is at the top of this article.

Frustrations and limitations

I’ve since bought a real ND filter, the 6-stop B+W I mentioned, so my welding glass hasn’t seen much use until I got it out to make this article. In making the wind turbine shots, I found what I think, (after some comparison testing), is a Grade 10 glass, very dark but still not dark enough to make even a short 1.6 second shot, (the shutter speed I determined was best to get the hint of motion I wanted on the turbine blades.) Longer exposures simply caused the blades to disappear entirely.

A side note here: long exposures can be a great way to make a crowd disappear when photographing a busy cityscape. The people move and so disappear during a long exposure while the static buildings and such stay put and show up in the photo.

Trying to darken the shot further, I put a polarizer on the lens, (dropping the exposure 2-stops), and then stacked the welder’s glass ND over that. It wasn’t a good combination. Too much, as the British say, “faffing about,” and I likely knocked my focus off slightly. Also, shooting through both the polarizer and the welding glass put too much “cheap glass” between the camera and the image, so the sharpness suffered.

A straight shot with no filter. 125/sec. f/22 ISO 100

A second trip to the Boise River provided an opportunity to see how a long exposure would depict the fast-moving spring runoff. I was able to use much longer exposures here, a few just over two minutes. I also made a 30-second exposure with the sun in the shot, something that wouldn’t have been possible with no filter even with the minimum ISO of 50 and the smallest aperture of f/22. Shooting long exposures in bright light is a big reason for using an ND filter.

A shot directly into the sun, and a shutter speed of 20 seconds, probably isn’t possible without a strong ND filter. I calculate the Grade 10 welder’s glass used here to give about 13-stops of light reduction. 20 seconds f/14 ISO 100

When to buy a real ND filter

You may find the welder’s glass technique a fun way to dip your photographic toe in the waters of long exposure photography. If you find you enjoy it and like the kinds of images you can make, save up and buy a good ND filter. However, if the technique is interesting, but not really your bag, then you will have discovered that having only spent a few dollars on your welder’s glass DIY version.

Either way, you will learn much more about creatively using your camera controls to make exciting photos and that’s what it’s all about. Learn and enjoy!

The post Try this DIY Neutral Density Filter for Long Exposure Photos appeared first on Digital Photography School. It was authored by Rick Ohnsman.

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Tips for Using Neutral Density Filters for Cityscape Photography at Blue Hour

19 Sep

Neutral density filters (ND filters) are essential tools when it comes to shooting cityscapes at blue hour. Even without an ND filter, you could shoot for a few seconds of exposure (using a small aperture like f/13) when the light falls towards the end of dusk.

But those opaque filters let you take even longer exposure photos (minutes, not just seconds), and create beautiful effects such as light trails, silky smooth water, rushing clouds, etc., by slowing down the shutter speed by a certain number of f-stops.

Singapore - Using Neutral Density Filters for Cityscape Photography at Blue Hour

This Marina Bay (Singapore) photo was shot with a 2-second exposure (at f/13) without using any ND filter. The sky looks good, but the water isn’t smoothed out at all, as that exposure is way too short to create silky smooth water effect that is seen in the photos to follow.

How ND Filters Make Your Exposure Longer

ND filters come in different strengths, some popular ones are 3-stop, 6-stop and 10-stop. The bigger the number, the darker the filter (i.e. the less light that is let through) and the longer the exposure will be.

For example, a base shutter speed of one second (i.e. when no filter is attached) can be extended to as long as 1024 seconds (over 17 minutes) with 10-stop ND filter attached, as each “stop” doubles the exposure time:

1 second > 2 seconds [1 stop] > 4 seconds [2 stops] > 8 seconds [3 stops] > 15 seconds [4 stops] > 30 seconds [5 stops] > 64 seconds [6 stops] > 128 seconds [7 stops] > 256 seconds [8 stops] > 512 seconds [9 stops] > 1024 seconds [10 stops]

It’s easy to calculate when a base shutter speed is a simple number like one second, but what about starting with, say, 1/15th of a second? This is where the Long Exposure Calculator app (for iOS) comes in handy and makes your life easier, as it automatically calculates a required shutter speed for you (look for an Android equivalent here).

ND filter and app - Using Neutral Density Filters for Cityscape Photography at Blue Hour

Neutral density (ND) filter (left) and Long Exposure Calculator app (right).

Using Different Strengths of ND Filters for Your Desired Effect

In this article, we’ll take a little deeper look at when to use which ND filter for your desired effect at blue hour.

3-Stop ND Filter

I don’t use 3-stop ND filter when taking cityscapes at a waterfront, as the strength is too mild to create a silky smooth water effect. Hence, my use of 3-stop ND filter is limited for scenes that have no water to be smoothed out, such as the photo below with light trails of moving cars, which doesn’t require a very long shutter speed.

Shanghai skyline - Using Neutral Density Filters for Cityscape Photography at Blue Hour

Shanghai skyline (China) shot with a 25-second exposure (f/8) using a B+W 3-Stop ND Filter (77mm). The base shutter speed was 3 seconds, ISO 100.

Singapore skyline shot with a 10-second exposure (f/13) using the same 3 -stop ND filter. The base shutter speed was 1.3 seconds, ISO 100.

This mild strength 3-stop ND filter (i.e. not so long exposure) isn’t all bad, though. It allows you to take a number of photos during blue hour, unlike more dense filters like a 6-stop ND filter where you can take no more than a few photos due to a longer exposure time required per photo.

6-Stop ND Filter

I almost exclusively use a 6-stop ND filter when shooting cityscapes at a waterfront. To create silky smooth water effects, slowing down 3 stops isn’t quite enough, but a 10-stop one is way too strong. For example, a base shutter speed of 2 seconds (i.e. with no filter attached) gets extended to 15 seconds (with 3-stop ND filter), 128 seconds (with a 6-stop ND filter) and whopping 34 minutes and 8 seconds (with a 10-stop ND filter) respectively.

Shanghai - Using Neutral Density Filters for Cityscape Photography at Blue Hour

Shanghai skyline (China) shot with a 164-second exposure (f/11) using a B+W 6-Stop ND Filter (77mm) in order to achieve my desired effect of silky smooth water. Had I used a 3-stop ND filter, the water wouldn’t have been smoothed out this much (base shutter speed: 2.5 seconds, ISO 100).

Marina Bay (Singapore) shot with a 163-second exposure (f/13) using the same 6-stop ND filter (base shutter speed: 2.5 seconds, ISO 100).

I typically aim to shoot with a base shutter speed of 2-3 seconds when using a 6-stop ND filter, which extends the exposure to 128 -192 seconds respectively. In order to create a silky smooth water effect, 2-3 minutes of exposure seems just right.

By the way, if you’re planning to buy only one filter for cityscape photography at blue hour, I’d recommend nothing but a 6-stop ND filter. I’ve probably photographed 90% of my cityscapes at blue hour using a 6-stop ND filter. It’s really a game changer if you are interested in doing this kind of photography.

10-Stop ND Filter

A 10-stop ND filter is a kind of special filter that lets you expose extremely long (longer than necessary in most cases!). Personally, I don’t really find 10-stop ND filter useful for shooting cityscapes at blue hour, as the exposure goes too long (even starting at a base shutter speed of 1/2 second gets extended to 8 and a half minutes), and digital noise caused by long exposure becomes too unbearable (even with in-camera long exposure noise reduction turned on).

So, this extreme filter’s use is rather limited to pre-dusk or even earlier in the day, not towards the end of dusk. In fact, one big advantage of a 10-stop ND filter is letting you take long exposure photos while the sky is still bright, which is something 3 and 6-stop ND filters aren’t up to the task of doing.

With a 10-stop ND filter, I usually aim to shoot with a base shutter speed of 1/4 or 1/3 second which is extended to 256 and 341 seconds respectively. I tend to avoid an exposure that exceeds 6-7 minutes, as long exposure noise starts to creep in.

Such a base shutter speed (1/4 or 1/3 second) can normally be achieved around sunset time or before, therefore you don’t really see deep bluish hue that’s typically seen at the prime time of the blue hour. Instead, your photo will have a surreal look that is very unique and distinctive to 10-stop ND filter.

Singapore skyline shot with a 258-second exposure (f/8) using B+W 10 Stop ND Filter (77mm) with a base shutter speed of 1/4 second, ISO 100.

Singapore skyline shot with a 259-second exposure (f/7.1) using the same 10-stop ND filter (base shutter speed: 1/4 second, ISO 100).

Conclusion

I hope this post helps you get started with shooting cityscape photos at blue hour using neutral density filters. I’m sure that you’ll be hooked in no time and can no longer shoot cityscapes at blue hour without one!

If you have any questions or tips to share, feel free to do so in the comments below.

The post Tips for Using Neutral Density Filters for Cityscape Photography at Blue Hour appeared first on Digital Photography School.

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Review of the Tiffen Variable Neutral Density Filter

28 May

In this review, I’d like to show you the Tiffen Variable Neutral Density Filter and give you my thoughts on it.

Review of the Tiffen Variable Neutral Density Filter - filter on a table

Review of the Tiffen Variable Neutral Density Filter - minimum setting

The markings on the edge indicate the strength being applied. Here it is set to MIN (minimum) or the lowest setting.

What is an ND or neutral density filter?

A neutral density filter is a piece of glass that goes in front of your lens in order to reduce the amount of light that enters the camera. One of its biggest purposes is to allow you to shoot at your desired aperture and shutter speed combination without worrying about it being too bright outside and your photos being overexposed.

This also grants you the capability to create beautiful motion blurs (using a long exposure) without worrying too heavily about lighting conditions. All of this being said, the main drawback of neutral density filters is needing to carry so many different ones of varying shades and densities.

Notice how the light from outside the window is overexposed, except for the part coming through the filter. The ND filter is blocking light and here you can clearly see the difference with the filter and without.

The Tiffen Variable Neutral Density Filter

The Tiffen Variable ND Filter aims to change that fact. By simply rotating the outer part of the filter, you can adjust it from an approximate range of two (ND 0.6) to eight (ND 2.4) stops. The profile of the ring is 9mm, so it’s rather thin and easy to maneuver.

The Tiffen Variable ND filter operates on the same principle as a circular polarizer, granting full manual capabilities to adjust your frame however you see fit. As such, the stops marked on the filter itself are intended to be used as reference points and do not actually signify official stops.

Like other Tiffen filters, the variable ND filter is made in the USA and sports high-quality optical glass using Tiffen’s ColorCore® technology. The kit includes a padded case and built-in lens-cloth to aid in the portability of this filter.

Review of the Tiffen Variable Neutral Density Filter - white dog in the sun

ISO: 100, shutter speed: 1/1600th, f/1.2 – the use of the filter here allowed me to shoot wide open even in bright sunlight.

How I use this filter with my photography

I will preface to say that although I should be using ND filters more in my work, I seldom do. I acquired this filter blind, having not used NDs often in my work. As someone who is consistently at the mercy of my client’s schedules, the Tiffen variable ND filter provided an apt solution to sessions booked around the infamous noon hour.

Motion blurs are not a common part of my photography – but I have now begun using the variable ND filter every single day to preserve my love of shallow-depths-of-field and wide apertures in unfavorable lighting conditions.

Review of the Tiffen Variable Neutral Density Filter - man in a field

ISO: 100, shutter speed: 1/8000th, f/1.2 – this exposure combination would result in overexposure in the bright sun without the use of the Tiffen Variable ND filter.

In real-life use of this filter, it was great to be able to visually see how the adjustments affected the image and maintain the integrity of the shot I wanted to take. Many of my clients enjoy my stylistic aesthetic of consistently using very low aperture numbers and a shallow depth of field in my work. This filter allows me to maintain this effect even on the brightest of days.

girl with a guitar portrait outdoors - Review of the Tiffen Variable Neutral Density Filter

ISO: 100, Shutter Speed: 1/8000, f/1.2

Using the filter

The test images here all featured my lively white dog, who previously was nearly impossible to properly expose with a wide aperture in the clear, bright noon sun. Each photograph features the same settings, with the ND ring being rotated to showcase how dark it can truly get.

These images were shot at high noon, in bright sun, with a 50mm f/1.2 lens wide open at 1.2. The ISO was set to 100, and the shutter speed to 1/1600th. The variable ND filter allowed me to darken the frame enough to ensure that the depth of field was kept intact.

It was very easy for me to figure out precisely what ND stop I needed due to being able to see the changes in real-time by rotating the cuff. The filter does have a slight blue cast and a severe blue tint when turned beyond the “maximum” markers on the filter.

Review of the Tiffen Variable Neutral Density Filter

ISO: 100, Shutter speed: 1/1600th, f/1.2

First impressions

Right off the bat, what I was really fond of about this filter is the ease at which I could adjust the stops; the rotation is very smooth and fluid. The filter itself is lightweight and features pristine Tiffen glass. The actual filter rim is intended to expand past the parameter of the lens glass to avoid an unintentional vignette, a welcome addition.

My only complaint would be there is a bit of a learning curve on actually attaching the filter to my lens, it took longer time than I would have initially liked due to the chunky rotating mount being in the way. It initially felt a bit loose on the lens, only to find that it was strictly my misuse/improper attachment causing the minor mishap.

Once this was remedied with a bit of practice, all was well. Unfortunately, the filter scale is hidden under the lens, so it also took some finagling to realign the filter stops. These are all minor inconveniences in the grand scheme of things, however.

portrait with blurred background - Review of the Tiffen Variable Neutral Density Filter

ISO: 100, Shutter Speed: 1/8000, f/1.2

Bonus tip: I went and purchased a step-down and step-up ring to be able to attach the filter to several of my other lenses, and I found that the addition of the ring actually helped screw the variable ND filter to my lenses because there was an additional amount of space to grip while I spun.

Purchasing a filter: Buy the filter to fit your largest lens and add some step-down rings to attach it to smaller ones. Then you only need one filter, not one for each lens you own.

Review of the Tiffen Variable Neutral Density Filter - dog with a blue ball

Notes on negative reviews

Many of the negative commentaries I have heard from this filter are due largely to misuse. Though it is possible to twist beyond the scopes or the maximum and minimum stop markers on the rotator mount, it isn’t useful nor practical from a photographic standpoint due to the distortion you can experience.

You should only range within the marked stops in order to use this filter effectively. I did experience chromatic aberration while using this filter but much of that is affected by the lens itself. This can easily be remedied in post-processing.

Review of the Tiffen Variable Neutral Density Filter - happy border collie

Tiffen Variable ND Filter and moving water

As I mentioned before, I don’t shoot a lot of moving things or added motion in my images. So our dPS editor, Darlene, has kindly provided some of her images of a waterfall shot with a variable ND filter to demonstrate its effects on that type of subject.

ISO 100, f/22, 1/10th with ND filter set to minimum.

ISO 100, f/22, o.3 seconds with ND filter.

ISO 100, f/22, 1.3 seconds with ND filter.

ISO 100, f/22, 4 seconds with ND filter.

ISO 100, f/22, 30 seconds with ND filter.

Notice how as the filter strength was increased, she was able to slow the shutter speed to change the effect of the flowing water. Attempting this in bright sun without a variable ND filter would result in extremely overexposed images.

For reference, her exposure without the filter was ISO 100, f/22, 1/20th, so the last shot above would have been 9 stops too bright. So having such a filter in your toolkit gives you a lot more options than shooting without it.

Summary

Retailing between $ 78.00 to $ 113.00 depending on the filter size, the price is very reasonable for the amount of use you can get out of this nifty piece of glass. The Tiffen Variable Neutral Density Filter is available in 52mm, 58mm, 62mm, 67mm, 72mm, 77mm, 82mm – plenty of diameters for all of your lenses. This filter is well-worth adding to any photographic collection.

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Kowloon Walled City: Drone Photos Reveal a Re-Growth of Urban Density

15 Jun

[ By SA Rogers in Drawing & Digital. ]

Once notorious both for its lawlessness and a maze of urban density so intense that sunlight couldn’t penetrate to its lowest levels, Kowloon Walled City was demolished in the 1990s, but a new version of it is rising from the ashes. Standing in stark contrast to the modern towers of Hong Kong just beyond its borders, Kowloon was an autonomous ‘city of anarchy’ built up from the ground like lasagna. 500 buildings were packed into less than seven acres, and there were no municipal services like trash collection or running water.

Outsiders called it the City of Darkness, and it certainly had a squalid appearance, but former residents remember it with fondness as a friendly and tight-knit community where everyone worked together to uphold their own poor but inventive society. But Hong Kong (and later, Britain – check out our previous coverage for the history) wasn’t too fond of the fact that it was run by the mob and packed with gambling dens and brothels, not to mention concerns about its structural soundness. So in 1993, all 50,000 inhabitants were cleared out and the whole thing was razed to the ground.

In its place came a 330,000-square-foot park full of paths and pavilions named after the city’s former streets and buildings. Ponds, gardens and floral walkways took the place of layer after layer of haphazard architecture. That park is still there – but it seems that the wild profusion of growth associated with Kowloon’s spirit couldn’t be contained. It may be modernized, with orderly rows of skyscrapers instead of a labyrinthine network of mismatched towers, but it’s growing more packed every year, and this level of density is creeping into the rest of Hong Kong, too.

Photographer Andy Yeung proves as much with his new drone photography series, Walled City. “The Kowloon Walled City was once the densest place on Earth. Hundreds of houses stacked on top of each other enclosed in the center of the structure. This notorious city was demolished in 1990s. However, if you look hard enough you will notice that the city is not dead.”

“Part of it still exists in many of current high density housing apartments where the only view out of the window is neighbor’s window. I hope this series can get people to think about claustrophobic living in Hong Kong from a new perspective.”

See the whole series at Andy Yeung’s website or on 500px.

[ By SA Rogers in Drawing & Digital. ]

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How to Use a Neutral Density Filter to Control Depth of Field

28 Apr

If your photography isn’t focused around landscapes, there’s a fair chance you don’t have a set of neutral density filters. These accessories are mainly for landscape photographers as their use in long exposure photography is invaluable. Because they are most associated with slow shutter speeds, their application in other genres, like portrait photography, isn’t immediately apparent. A neutral density filter can, however, be vital to gain control over your depth of field in some situations.

This tutorial will show a quick and dirty tip for two scenarios in which to use ND filters to control the depth of field in your photography; one outdoors in natural light and the other in a studio environment.

What is a Neutral Density filter?

At its most basic, a neutral density filter is a piece of material (usually plastic, resin, or glass depending on the quality) you place between your lens and subject to reduce the amount of light entering your camera. This will result in a slower shutter speed being required, a larger aperture, or a higher ISO in order to achieve the correct exposure. The filters come in different strengths, usually ranging from a loss of one stop to three stops of light. For example; if you are metering an exposure of f/8 at 1/250th and you place a 1-stop ND filter on your lens, to compensate you will need to change either your shutter speed to 1/125th or your aperture to f/5.6.

How to Use a Neutral Density Filter to Control Depth of Field

Neutral density filters are a valuable tool in landscape photography, but they are also useful in other genres.

In terms of photographing landscapes in low light, you can probably see how they are useful. A 2-stop ND filter turns a 2-second exposure into an 8-second exposure. Alternatively, it turns an 8-second exposure into a 32-second exposure. If you’re trying to smooth out water or clouds on a windy day, an ND filter makes it a breeze.

For portraits, however, you will almost never want to reduce the shutter speed. If anything, you will often want to increase it. Why, then, would you want to put something on your lens that reduces the amount of light coming in? The answer is simple – when you have too much light in the first place.

Outdoors

If you’re taking photographs outdoors on a bright sunny day, you may find yourself limited to smaller apertures like f/11 and f/16. This is great for capturing a high amount of detail, not so much if you would like a shallow depth of field.

This is where a neutral density filter comes in. A 2-stop ND filter will turn an aperture of f/8 into f/4. A 3-stop ND filter will make it f/2.8, making it far easier to obscure a cluttered background with a shallow depth of field.

Both of these images were taken moments apart. Left: Shot at f/8 without an ND filter. Right: Shot at f/4 with a 2-stop ND filter.

In the studio

The idea behind using the ND filter in a studio environment is the same as it is outdoors. The main difference is that with natural light, you can always wait until later in the day. With high powered studio lights, that’s not always the case. If you’re aiming for soft light , you need to get your light source in close to your subject. If you have high-powered studio strobes, you may not be able to turn the power down low enough to use large apertures.

Again, a quick solution is to pop a neutral density filter on your lens. By doing so, you don’t have to sacrifice the softness of your light and you gain the benefit of complete control over depth of field.

Taken in a studio environment at f/8

Adding a neutral density filter reduced the aperture to f/4 without changing anything else in the scene.

Bonus round

Chances are that throughout this tutorial, the problem-solving side of your brain has figured out that all of these scenarios have a multitude of other methods to solve them. Outdoors, you could use a diffuser that cuts down exposure, or you could move to an area of open shade where the intensity of the light is reduced. In a studio, it’s often easy enough to move a light backward or to move your subject. Using an ND filter just adds another potential tool, and like most techniques, it is neither a be all or end all, nor is it required. It’s just another option.

That said, what do you do in a situation where you can’t control the intensity of your light and if you were to move it even an inch further away from the subject, everything in the frame would completely change? Same with diffusing it? I ran across this exact situation recently, as illustrated below, and it was a 2-stop ND filter that solved the problem.

Moving the light source in this instance, would have ruined the effect of the lighting. A neutral density filter allowed for a larger aperture while still allowing the camera to be handheld.

That’s it

In the end, if you want to have full control over your camera and the depth of field in your images, then neutral density filters deserve a place in your kit bag even if you never set eyes on a landscape.

The post How to Use a Neutral Density Filter to Control Depth of Field by John McIntire appeared first on Digital Photography School.

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STC adds 6-stop neutral density to its clip-on sensor filter range

01 Apr

Specialist filter manufacturer STC Optical Ltd has expanded its range of Clip filters to include a ND64 with infrared-cut properties. The new filter, which clips directly in front of the camera’s sensor instead of over the front of the lens, provides 6 stops of light reduction while maintaining accurate colors by preventing infrared light from passing freely during the exposure.

The benefit of using filters over the sensor is that the same filter can be used whichever lens is fitted, so users don’t have to buy a separate size for each lens diameter, or a different adapter ring. These kinds of filters are especially useful when used with ultra-wide lenses as they present no danger of vignetting and they fit behind lenses that can’t accept conventional front-element screw-in filters.

With wide, as well as normal, lenses having the filter behind the lens avoids the problems of flare that adding glass in front of the lens can create. It also side-steps the problem of reflections on the back-side of the filter that can be a danger during long exposures when using filter holders that don’t hold the filter flat against the front of the lens.

Using this sort of ND filter will potentially be of benefit not only for creating long-exposure still images but also for video work. And of course with the filter remaining in place in the camera, changing lenses will take less time as there’s no need to screw off and reattached the filter.

Since the filter prevents DSLR mirrors returning to their normal position, it must be attached in live view mode. STC claims that it is perfectly safe to leave the filter in place even with the camera powered off, since the filter is designed to support the mirror, and prevent it from dropping.

A full list of compatible Nikon, Canon and Sony full frame and Canon APS-C bodies is available on the STC Optical website. The filters cost $ 90.

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Review of the New Formatt Hitech Firecrest Filter Holder and Neutral Density Filters

16 Mar

This article is an overview of the Formatt Hitech Firecrest Filter Holder system and their neutral density filters.

Long exposure is one of those magical types of photography that once people start doing it, they nearly always fall in love with the technique. They then begin their quest for the right conditions to take those photos, along with the right gear. The filters you use are important and, so is the holder for them.

Overview of the Formatt Hitech Filter Holder and Neutral Density Filters

Sunset at St. Kilda Pier, this was taken with the Formatt Hitech Filter Holder and their 10-stop ND filter.

Long exposure photography is becoming so popular, but with it come lots of issues to deal with. The most important one is light and stopping any from getting into the camera that may ruin your images. Another one that you hear many complaining about is color casts caused by the filters they are using.

Have the right gear to get what you attempting is so important. Formatt Hitech has been listening to their users and has come up with a new holder system for their 100mm filters that addresses many of these problems.

Formatt Hitech Filter Holder

The new filter holder from Formatt Hitech is designed to completely enclose the filter so no light can get in around it once the filter is in place. It removes the need for the foam gasket on the back of the filter, as the holder has one on it to help seal the filter into place.

Formatt Hitech has put a great deal of thought into what you will need for long exposure photography, and along with the holder come some other surprises.

The Formatt Hitech filter holder in use at Docklands.

What’s in the box

This company does produce some of the loveliest packaging that I’ve seen. The boxes have a soft, almost suede feel. It is hard to throw them away, in fact, I haven’t been able to.

When the package arrives and you open the box you will see the holder, but you will also see an 82mm adaptor ring and a series of step-down rings. So often in the past when buying the adaptor rings you have had to make a choice about which lens you will fit it to and get the ring to fit that one. Formatt Hitech gives you the adaptor ring for the largest possible filter size and the step-down rings to fit other lenses.

Wrapped in paper, you will find a polarizer that fits into the adapter ring. This filter fits in the back of the holder system very neatly, and your neutral density filters then fit in front of it. There is a geared control wheel that allows you to turn the filter as needed.

The added benefit here is the ability to use the polarizer in the adapter ring on its own. You don’t have to attach the holder at all.

Formatt Hitech Filter holder and ND Filters

Everything that you get with the Formatt Hitech filter holder. Photo courtesy of Formatt Hitech

Using it for the first time

When you first open the box it can seem a bit overwhelming and when you try to use the system, it’s a little confusing. It feels like you will break it when you try to pull it apart, but it is designed for rough use.

If you still can’t work it out Formatt Hitech has a video which they recommend that you watch (see below). The brackets around the holder are often a little stiff to begin with, but they do get easier and loosen up with use. Watching the video will help you get past that.

Attaching the holder onto the adaptor ring can take some getting used to as well. It is bit fiddly, but with practice, you will get better at it, and faster. You can do it with one hand, it simply clicks onto the ring. It is quite durable and will take a lot of handling. The holder stays very firmly on the adaptor ring.

Using the filter to get a long exposure of Pyramid Rock.

Why is it good to have a filter holder like this?

If you looked at the old filter holder that was available, even with the foam gasket, you could see gaps where it was possible for light to get through. When you want to create a perfect long exposure you need to make sure that there are no leaks. The benefits of this particular filter holder system is that it removes the possibilities of those gaps and creates a more light tight cocoon around your filter.

City of Melbourne from across the river. Taken with the new Formatt Hitech Filter holder and their 16-stop ND filter.

Using it

Out in the field, the system does work well. But, having to remove both brackets around the holder just to the change filter, or add one, is a bit harder and takes more time. The benefits the brackets provide in other ways (light tightness) certainly make up for it, though.

There have been a couple of instances of vignetting, but it is very slight and only seems to happen when the lens is very wide, for example at 24mm.

When you first use the bracket it seems like you can’t use graduated filters in the holder. However, there are sections at the top and bottom that can be removed that will allow you to use 100x150mm filters. There are vented end caps that allow the filters to poke through, while at the same time helping to retain that light seal.

Wonky Pier at Sullivan Pier. Long exposure using the new holder and the Formatt Hitech Firecrest 13-stop ND Filter.

The Format Hitech filters

It is logical that if you are going to use the holder then you should also use the Formatt Hitech filters as well. Their Firecrest series are very neutral and have no color cast, even when underexposing.

They are made in the UK using high-quality optical glass that is bonded together, so the coating is sandwiched between them. This helps to protect the filters and also makes them much harder to scratch. If you do scratch them then you are just doing it to the outside and not the coating itself.

Tenby Point and tree with the tide coming in. Using the holder with the 10-stop ND filter.

Cost

Formatt Hitech filters aren’t cheap, with the filter holder retailing around $ 170 USD, but you do get quite a bit for your money. The filters are pricey, but if you love long exposure photography then it’s worth it. Plus, if you look after them, don’t drop them, you could have them forever.

They also sell kits, which can help you save money on the initial outlay. They all have the filter holder and various filters depending on what you are looking for.

Long exposure taken at Princes Pier using the new holder and the Formatt Hitech Firecrest 10-stop ND filter.

Conclusion

Long exposure photography is an addictive style and many who start can’t stop. If you love it and want to get the best possible photos, then you have to consider the new Firecrest Filter Holder from Formatt Hitech. A holder that stops light from entering through your lens is a great start. Combined with the filters, you are on your way to creating some magical images.

If you want to compare to other systems have a look at these as well:

Review of the Wine Country Camera Filter Holder System
Switching from LEE to NiSi Filters: Was it a Mistake?

The post Review of the New Formatt Hitech Firecrest Filter Holder and Neutral Density Filters by Leanne Cole appeared first on Digital Photography School.

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