RSS
 

Posts Tagged ‘Terms’

Photography Terminology: A Glossary of 69 Essential Photographic Terms

06 Apr

The post Photography Terminology: A Glossary of 69 Essential Photographic Terms appeared first on Digital Photography School. It was authored by Darlene Hildebrandt.

photography terminology: a glossary of 69 terms

Are you overwhelmed or confused by photography terminology? Do you want to speak “photographer” like the pros?

That’s what this article is all about.

I’ll go over some of the most common technical photography terms as well as some less common slang and photographer jargon. By the end, I promise you will have a better grasp of the language. You’ll even be able to have a conversation with a seasoned pro and hold your own!

Let’s get started.

Basic photography terms

These are the photography terms you’ll find in your camera’s manual and in most beginner tutorials:

  • Aperture – The variable opening in the lens through which light passes to the film or digital sensor. Aperture is measured in f-stops. I like to compare it to your pupil, which opens and closes to allow more or less light into your eye depending on the brightness level of the room.
  • Bracketing – Taking a series of images at different exposures. You may see a setting on your camera that says AEB (auto exposure bracketing). Bracketing is often used when creating HDR images or in difficult lighting situations where you may want to have a range of exposures from light to dark.
  • Bulb – the “B” setting on your camera where the shutter remains open for as long as the button or cable release (remote trigger) is pressed.
  • DSLR – A digital single-lens reflex camera. Any digital camera with interchangeable lenses where the image is viewed using a mirror and prism and the image is taken directly through the lens. What you see in your viewfinder is what the lens sees.
  • EV – Exposure value; this is a number that represents the various different combinations of aperture and shutter speed that can create the same exposure effect.
  • Exposure compensation – Modifying the shutter speed or aperture from the camera’s recommended exposure to create a certain effect or correct for exposure problems. Your camera reads light bouncing off your subject and is designed to expose for medium gray. So when photographing a subject that is lighter or darker than 18% gray, you can use this setting to tell the camera the proper exposure (by dialing in – or + exposure compensation).
  • Exposure – The total amount of light reaching the digital sensor. It is determined by the aperture, shutter speed, and ISO.
  • F-stop – A measure of the aperture opening in the lens defined by dividing the focal length of the lens by the aperture diameter. The sequence of f-stops features multiples of the square root of 2 (1.4): 1, 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, etc. Though these numbers are rather cryptic, make sure to remember that each step is double the amount of light. Know that, and you’ve won half the battle.
  • ISO – Represents the sensitivity of your camera’s digital sensor to light. The lower the number (ISO 100), the less sensitive to light; the higher the number (ISO 3200), the more sensitive to light. A higher ISO allows you to shoot in low-light conditions.
  • Shutter speed – The amount of time the shutter is open during an exposure. The shutter speed controls the appearance of motion. Use a fast shutter speed (such as 1/2000s) to freeze motion or a slow shutter speed (such as 1/30s or longer) to blur moving objects.
  • Zoom lens – Any lens that has a variable focal length, such as a 24-70mm or an 18-55mm lens. You generally zoom in or out by rotating the barrel of the lens.
  • Prime or fixed lens – Any lens that does not zoom and features a set focal length, such as a nifty 50mm lens.
  • Remote trigger or digital cable release – A device that allows the camera to be fired without pressing the shutter button or touching the camera. Helps eliminate camera movement during long exposures.
  • Macro lens – A lens that focuses very close to a subject, so you can capture highly detailed, magnified images.
  • “Normal” lens – Generally a 50mm lens (on a full-frame camera). This lens closely parallels what the human eye sees. If you have a crop-sensor camera, a “normal” lens will be closer to 35mm.
  • Telephoto lens – Offers a tighter field of view than a normal lens (i.e., it takes more magnified images). Generally from around 70mm to 300mm. A super-telephoto lens is usually 300mm or longer.
  • Wide-angle lens – A lens that features a wider field of view than a normal lens. Generally spans from over 10mm to under 50mm. Depending on the focal length, there may also be edge distortion (i.e., in super wide-angle lenses).
  • Tilt-shift lens – A special-effect lens. Allows for realignment of the plane of focus (tilt). Allows for adjusting the placement of the subject within the frame without angling the camera, thus keeping parallel lines from converging (shift). A popular lens for architectural and landscape photographers and is becoming more widely used by portrait photographers to create a unique, stylized look.
  • Camera resolution – The dimensions your camera’s sensor is capable of capturing, expressed in megapixels. This is not the only factor in image quality, but the greater the resolution, the larger the prints you can produce without significant loss of quality (generally speaking).
  • JPEG vs RAW – Two different image file types. Most cameras have the ability to shoot in JPEG and RAW. If you choose JPEG, the camera will shoot a RAW file, process it using the picture style you’ve selected in your menu, save it as a JPEG, and discard the RAW version. If you choose RAW, the resulting file will be larger, carry more information, and require software to process. It gives you – the photographer – more control over the final look of the image.
  • Full-frame vs crop/APS-C sensor – A full-frame sensor is roughly the size of 35mm film. Most lenses create a circle of light just large enough to cover the 35mm sensor area. But in a crop-sensor camera, the physical size of the sensor is smaller; it only captures a portion of the entire image the lens is projecting, effectively cropping out part of the shot. Common crop factors are 1.5x and 1.6x, so if you use a 50mm lens on an APS-C camera, it offers a 75mm focal length equivalent.
  • Camera modes – There are four standard camera modes. Auto mode selects settings without user input. Manual mode allows the user to control the ISO, shutter speed, and aperture. Shutter Priority mode allows the user to select the ISO and shutter speed while the camera selects the aperture. Aperture Priority mode allows the user to select the ISO and aperture while the camera picks the shutter speed. Program mode allows the user to select the ISO while the camera picks the aperture and shutter speed.

Lighting and portrait photography terms

  • Ambient light – Also referred to as available light. Ambient light occurs in the scene without adding any flash or light modifiers. It can be daylight, or it can be artificial light such as tungsten or fluorescent bulbs.
  • Main light or key light – The main light source for a photograph. It could be the sun, a studio strobe, a flash, a reflector, or something else. It’s the source that produces the pattern of light on the subject with the most intensity.
  • Fill light – The light source that is secondary to the key light. Used to “fill” in the shadows. Can be produced with a flash, a reflector, or a studio strobe.
  • Lighting pattern – The way the light falls on the subject’s face (e.g., at a 45-degree angle).
  • Lighting ratio – A comparison between the intensity (brightness) of the main light and the fill light. In other words: the difference between the lit and shadow sides of the subject’s face.
  • Incident light meter – A handheld device that measures the amount of light falling on a subject. An incident meter is not fooled by the brightness range of the subject, whereas in-camera reflective meters can be fooled (resulting in overexposure and underexposure).
  • Speedlight – A small, portable flash that can attach to your camera’s hot shoe or stand on its own when activated remotely.
  • Reflector – A device used to reflect light (generally back toward the subject). It can be a specialized, factory-made reflector (I recommend getting a 5-in-1), or a piece of white cardboard.
  • Light meter – A device that measures the amount of light in a scene. Pretty much all modern cameras offer a built-in light meter, though it uses reflective readings (see the entry on incident light meters, above).
  • Remote flash trigger – A device used to fire speedlights off-camera.
  • Subtractive lighting – Taking away light to create a darker look. It often involves holding a reflector or an opaque panel over the subject’s head to block light from above and open up deep eye shadows caused by overhead lighting. It can also involve holding a black reflector opposite your main light to create a deeper shadow (i.e., essentially reflecting black onto the subject instead of light.)
  • Hard light – Harsh or non-diffused light such as that produced by bright sunlight, a small speedlight, or an on-camera flash. Creates harsh shadows with well-defined edges, contrast, and texture (if used at an angle to the subject). Emphasizes texture, lines, and wrinkles. Often used to create a more dramatic type of portrait.
  • Soft light – Diffused light, such as that from an overcast sky, north-facing window with no direct light, or a large studio softbox. This type of light produces soft shadows with soft edges, lower contrast, and less texture. Soft light is generally preferred by most wedding and portrait photographers because it flatters the subject.
  • Edge transfer – How quickly shadow edges go from dark to light. With harsh light, the edge transfer is very defined and sudden (almost a clear line). With soft lighting, the edge transfer is much more subtle – almost imperceptible – as it gradually changes from dark to light.
  • Flash sync – The synchronization of the firing of an electronic flash and the shutter speed. You need to know what shutter speed your camera syncs at; otherwise, if you use a too-fast shutter speed, you may get a partially illuminated image. For most cameras, the sync speed is around 1/200s.

Slang and photography jargon

Here are a few other photography terms that are a bit more advanced (including some wacky jargon and slang!). Become familiar with this terminology so you can talk to pros with confidence.

  • Fast glass – Refers to a lens with a very large maximum aperture (such as f/1.8 or f/1.2). The lens is “fast” because it lets you shoot with a fast shutter speed.
  • Chimping – Slang term for looking at the back of your camera after every image. Has a negative connotation; if you chimp, you’re spending too much time reviewing images on the camera and not enough time shooting.
  • Bokeh – The out-of-focus blurred bits in an image background. Most often bokeh occurs when small light sources are in the background.
  • Depth of field (DOF or DoF) – The distance between the nearest and farthest objects in your scene that appear in focus. Controlled by many factors, including the aperture, lens focal length, and distance to the subject.
  • Hyperfocal distance – The focus distance providing the maximum depth of field for a particular aperture and focal length. Older prime lenses often have hyperfocal distance marks to aid in finding this depth-of-field sweet spot. With today’s lenses, it is possible to calculate the hyperfocal distance, but it takes a bit more work and a hyperfocal distance calculator.
  • Gobo – Something used to block unwanted or stray light from falling onto the subject. Often the dark side of a reflector is used as a gobo.
  • Scrim – A translucent device used to diffuse and soften the light. Can be a reflector with a translucent panel. Scrims can be made extremely large and clamped in place to create shade even in direct sunlight.
  • Shutter lag – The slight delay from the time you press the shutter button to the time the shutter actually opens. In DSLRs and mirrorless cameras, shutter lag is minimal and almost unnoticeable. In smaller point-and-shoot cameras, the delay is more pronounced (and can cause you to miss shots of fast-moving subjects).
  • Chromatic aberration – Color fringing that can appear in areas of images where dark meets light (e.g., the edge of a building against the sky). CA is correctable to a great degree using Photoshop, Lightroom, and most other editing software.
  • Rear-curtain sync – Rear-curtain sync fires the flash at the end of an exposure. By default, most cameras are set to front-curtain sync (i.e., if the flash fires, it does so at the beginning of the exposure). When shooting a moving subject, front-curtain sync will put any motion blur in front of the subject, whereas rear-curtain sync will place the blur behind the subject. Neither is wrong; it depends on the effect you’re after.
  • Camera shake – When a camera moves during an exposure and creates blur.
  • Lens flare – Stray light that creates haze, circles, or other artifacts in an image. Some photographers actually desire lens flare; they position their cameras to create flare and use it as a compositional element.
  • Kelvin – The absolute measurement of color temperature. Lower numbers represent warmer colors like orange (tungsten light), whereas the higher numbers are cooler (blues). Play with the color temperature to create different effects.
  • ND filter – Stands for neutral density filter. It’s a filter designed to go in front of the lens to block out some of the light entering the camera. Often used by landscape photographers to get slow shutter speeds when photographing waterfalls and streams in full daylight.
  • Panning – The act of using a slow shutter speed and moving the camera in the same direction as a moving subject. Creates an artistic, blurred background.
  • Stopping down – Closing down the aperture to a smaller opening (e.g., going from f/5.6 to f/8).
  • TTL and ETTL – TTL stands for through the lens; it refers to the metering system in regard to flash exposure. The flash emits light until it is turned off by the camera sensor. ETTL stands for evaluative through-the-lens metering. It fires a “preflash” to evaluate and calculate for lost light, then compensates and fires the main flash. It happens so fast you do not see two flashes.
  • Photog – Short for “photographer.” Something pros often call each other.
  • Glass – A lens. As in, “What glass do you own?”
  • Golden hour – Also called “magic hour.” This is the hour or two right before sunset and right after sunrise. The sun is low on the horizon, and it is an optimal time for photography.
  • Spray and pray – Shoot as many images as possible while praying you get something good.
  • Blown out – An image with no details in the white areas.
  • Clipped – Either blown out areas (above) or dark, detailless shadows.
  • Grip-and-grin – A quick photoshoot at an event or a setup with two people shaking hands. Most portrait and event photographers have to shoot these at some point in their careers.
  • Selfie – A self-portrait.
  • SOOC – Straight out of camera; an image with no post-processing.
  • Dust bunnies – Dark spots that appear on an image caused by bits of dust on the digital sensor.
  • Pixel peeper – Someone who spends too much time looking at images magnified in Photoshop.
  • Nifty fifty – A 50mm prime lens. Great to have!
  • ACR – Adobe Camera Raw. The editing software that’s packaged alongside Photoshop.
  • Flash and drag – The method of using a slow shutter speed combined with flash to capture more of the ambient light in proportion to the flash.
  • Wide open – Using your lens with the aperture at its widest setting (f/1.8, for example).

Photography terminology: final words

Whew! That was a long list. If you made it this far, congratulations; you know how to use photography terms like a pro.

So get out there and start practicing your photography terminology. Be sure to have lots of fun!

Now over to you:

What photography terms do you struggle with? Do you have any more terms I should add to this list? Share your thoughts in the comments below!

The post Photography Terminology: A Glossary of 69 Essential Photographic Terms appeared first on Digital Photography School. It was authored by Darlene Hildebrandt.


Digital Photography School

 
Comments Off on Photography Terminology: A Glossary of 69 Essential Photographic Terms

Posted in Photography

 

Instagram clarifies its sublicense terms don’t cover embedded images

06 Jun

Instagram has made a surprising announcement that will have big implications for photographers and anyone who uses its built-in ‘share’ function: it does not grant sublicenses to users for embedded images. The revelation comes amid lawsuits over embedded Instagram posts and allegations that embedding without permission or a license constitutes copyright infringement.

Instagram features a share button that, among other things, enables users to embed public posts on other sites. This is a common way to include social media content in an article or blog post, but that may change with the bombshell announcement from Instagram. In a statement to Ars Technica, Instagram’s parent company Facebook said that despite the fact that ‘while our terms allow us to grant a sub-license, we do not grant one for our embeds API.’

The company went on to state that users must get permission to embed the image from the copyright holder, this despite the fact that Instagram offers the embed function on all public images and does not allow individual users to disable the sharing option.

In light of this, users who embed Instagram posts without first getting permission or a license from the photographer may face a copyright lawsuit. We’ve seen two cases of this issue appear in court in recent months, one involving digital media website Mashable and, more recently, another involving Newsweek.

In the first case, photographer Stephanie Sinclair filed a copyright lawsuit against Mashable after it embedded one of her Instagram posts without permission. The court ultimately sided with Mashable and ruled that Instagram’s terms allowed it to grant a sublicense for images. In the Newsweek case, however, the court sided with photographer Elliot McGucken and found that more details are needed to determine whether Instagram’s terms cover sublicenses for embedded images.

In the Newsweek case, Judge Katherine Failla references the Mashable ruling, stating:

‘The Court finds Judge Wood’s decision to be well-reasoned and sees little cause to disagree with that court’s reading of Instagram’s Terms of Use and other policies … The Terms of Use unequivocally grant Instagram a license to sublicense Plaintiff’s publicly posted content … Nevertheless, the Court cannot dismiss Plaintiff’s claims based on this licensing theory at this stage in the litigation … there is no evidence before the Court of a sublicense between Instagram and Defendant … Although Instagram’s various terms and policies clearly foresee the possibility of entities such as Defendant using web embeds to share other users’ content … none of them expressly grants a sublicense to those who embed publicly posted content.’

Ars Technica contacted Facebook to find out whether its sublicense terms cover embedded images — and the company says it does not. The revelation was very surprising and will fundamentally change the way users share Instagram posts, though it is a win for professional photographers who are frustrated over how the platform currently operates.

As Sinclair pointed out in the Mashable lawsuit, Instagram is one of the most popular image-sharing websites, but it gives photographers little control over how their images are used: they can either make the images public and therefore open to embedding or make them private to restrict embedding, limiting the platform’s usefulness for photographers seeking an audience.

With Facebook’s public statement on Instagram’s lack of sublicensing for embedded images, future copyright cases will not be able to follow in Mashable’s footsteps. Instagram has been criticized for failing to give photographers more control over how their images are shared and this new revelation will likely add fuel to that fire.

Though users are warned when they embed an image that they must follow Instagram’s terms, most are unlikely to actually read those terms and may not understand the intricacies of sublicensing and how it relates to embedded content. This would put unaware users at risk of copyright lawsuits for using the feature Instagram makes readily available.

In a statement to Ars Technica, Instagram said that it is ‘exploring the possibility’ of allowing photographers to control whether their images can be embedded…presumably without having to make their account private. It is far from certain whether this feature will actually be deployed, however, and how long it may take to introduce this additional control.

Whether Instagram’s statement will have a far-reaching impact on copyright lawsuits and how content is shared on the Internet is yet to be seen, however. Questions remain over the ‘server test’ and whether Instagram, not its users, is liable for infringing use of its embed feature. It seems likely that Newsweek will appeal the judge’s ruling with a server test defense, but only the future will tell how this all plays out.

Articles: Digital Photography Review (dpreview.com)

 
Comments Off on Instagram clarifies its sublicense terms don’t cover embedded images

Posted in Uncategorized

 

500px combines Terms of Service and Contributor Agreement, confusing some users

24 Dec

Photography community 500px recently updated its Terms of Service, adding its Contributor Agreement into the TOS to provide a single destination for both. As tends to be the case any time a social network or other service updates its TOS, some users have picked through the text and come away frightened. A recent analysis of the changes by PetaPixel, however, finds little to be concerned about.

500px released its updated Terms of Service earlier this month; users were alerted to the change when the service prompted them to read and agree to the latest TOS. A number of users posted concerns about various snippets on social media, questioning the terms and, in some cases, demanding the company make changes.

PetaPixel recently dug into the latest Terms of Service and compared it to 500px’s older archived TOS, finding that the language has remained essentially unchanged. Some users may be surprised by the changes because of the inclusion of the Contributor Agreement within the updated TOS. Those added terms only apply to users who choose to sell images through the platform, however.

Users always retain the option of deleting their 500px account. The latest Terms of Service explains that:

Upon termination (by 500px or you), 500px will remove your Visual Content from licensing within 180 days and will inform all distributors that the Visual Content should be removed during that time period, provided however that 500px (and our distributors) may retain digital copies of Visual Content for archival and record-keeping purposes. 500px will continue to make payments due to you after termination in accordance with these Terms.

Via: PetaPixel

Articles: Digital Photography Review (dpreview.com)

 
Comments Off on 500px combines Terms of Service and Contributor Agreement, confusing some users

Posted in Uncategorized

 

DPReview TV: Photo lingo 101 – a guide to common photographic terms

15 Jun

It’s back to basics in this week’s episode as Chris and Jordan break down some common photographic terms that might not be familiar to newer photographers. Learn all about IBIS, BSI and CIPA, as well as a, shall we say, ‘creative’ origin story for the word ‘bokeh.’

Get new episodes of DPReview TV every week by subscribing to our YouTube channel!

  • Introduction
  • Eye Relief/Eye Point
  • EVF vs. OVF
  • CIPA Rating
  • Shutter life
  • BSI
  • IBIS vs. OIS
  • Bokeh
  • Diffraction
  • Sunstars
  • Dynamic range
  • Wrap-up

Articles: Digital Photography Review (dpreview.com)

 
Comments Off on DPReview TV: Photo lingo 101 – a guide to common photographic terms

Posted in Uncategorized

 

How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

22 Feb

What is it that makes one picture appear dull and another more striking? What is it that makes some tones appear detailed and others smooth and transient? The answer to both of these questions involves the issues of color hue, color purity, and tone distribution.

Prague A - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

This street scene in Prague is the original underexposed camera image.

Prague B - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

The same image after tonal and color adjustments have been applied.

The science of color and tone

All color detail is determined by these three elements. In the Photoshop/Lightroom world, you’ll recognize these terms as HSL or Hue, Saturation, and Luminance. The world of photography is both an art and a science. The science part is filled with graphs, measurements, and strange words that most people don’t encounter every day.

These terms come from the scientific vocabulary of engineers, chemists, and mathematicians in the photographic trade. When digital cameras were introduced to the general public years ago, suddenly everybody could push around the colors and tonal range in their own pictures. While Adobe Photoshop provided a serious workshop, it showed up with a boatload of technical color science terms.

Unfortunately, if you don’t fully understand the terms, you may not be taking full advantage of the controls they provide. In this article, I’ll do my best to bring these terms down to Earth and make them understandable. We’ll get past the technical jargon and get into the practical application of these terms.

Hue, Saturation, and Lightness

Hue, Saturation, Lightness (luminance) are the irreducible minimum building blocks involved in good color editing and reproduction. While there are many more issues to be addressed in the processing of an image, these three are the make-or-break elements that must be understood and adjusted if you want your color images to catch a viewer’s eye.

Incidentally, when editing your images, these elements should be addressed in that very order; value (hue), intensity (saturation), and tonality (luminance). While hue and saturation concern color, luminance refers to the tonal structure of an image; pretty much an issue of dark versus light.

The Saturation slider affects the intensity of the color in an image. This is a powerful tool; exercise restraint.

Genoa A - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

The Saturation effect on a Genoa Italy cathedral – normal saturation levels.

How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

Genoa B - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

None.

HSL Dialog Sat Low - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

Genoa C - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

Oversaturated.

HSL Dialog Sat High - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

A Primer on Image Detail

Contrast usually refers to the overall light-to-dark extremes of an image but the real power of post-production editing is in pushing the tonal values around inside the overall range.

But if you really want to make the detail in your image stand out, you must adjust the internal contrast of the image. The biggest difference-maker adjustment should be the middle tones of your images; tones in-between the lightest and the darkest in your image.

TrafalgarSq A - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

Trafalgar Sq O Levels - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

The middle slider in Photoshop’s Levels dialog is referred to as the gamma slider. Gamma is another one of those legacy scientific terms that you can think of as a “mid-tone” adjustment. Moving this elementary slider from left to right actually shifts the entire middle range of tones from lighter to darker.

TrafalgarSq B - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

This picture of the King Charles statue in London’s Trafalgar Square is backlit and was dark, but a simple middle tone adjustment opened up the shadows and revealed hidden detail.

TrafalgarSq A Levels - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

Photoshop’s Levels tool is the most basic of tonal controls. There are actually several much more effective tonal shaping tools available in Photoshop and even more comprehensive controls in Adobe Camera Raw and Lightroom. We won’t get into a thorough discussion of these tone adjustment tools and workflow recommendations in this article (perhaps at a later time).

Leaves A - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

Leaves B - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

This picture of winter leaves was fairly well exposed but required both tonal and color adjustments to reveal the rich colors in the original scene.

Camera Raw dialog - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

Editing for Tonality

There’s a reason why tone adjustment should be your number one issue in image preparation; even more critical than color accuracy.

Your eyesight has tonal perception and interpretation capabilities that far exceed the dynamic range of any digital camera. Make no mistake, capturing seven stops of light range is an amazing feat. But capturing this wide range of tones doesn’t automatically translate into detail, image definition, or good tonal distinction.

Properly reassigning those internal tones to more closely match what your eyes see is where the real editing magic happens. Hang with me here because this will get a bit involved, but I think it will definitely be worth your time.

LinearCapture Eye Camera - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

This chart shows the difference between the way your eye registers light and how your camera records it.

Camera View – Human View

Your camera’s image sensor records light quite differently than your eye perceives it. The camera actually records a lot of data from the lighter portion of the scene and very little data from the darker portion. The image sensors capture light in a linear fashion. Unfortunately, humans view the lighting in scenes in a logarithmic fashion.

You might say that original camera files usually benefit from a “fashion” adjustment, generally lightening the middle tones. Camera images that don’t get their tonal values adjusted almost always lose detail in the darker areas of the image. Virtually all camera images benefit from internal adjustments.

Chrominance and Luminance Explained

Chrominance deals with the color component of an image while luminance deals with the contrast or tonality component of an image.

Chroma refers to the color in an image while luma describes the non-color or tonal part. Achromatic is a fancy scientific word that is pretty simple to understand. Remember your high school English… the prefix “a” means “without,” so a-chromatic literally means without color.

In the HSL model of color, hue, and saturation fall in the chrominance column while tonality and contrast are on the luminance column (the structural or tonal backbone of an image).

Basic Luminosity Adjustments

Where does the term “luminance” come from? Light is measured in lumens. A lumen is the smallest measurable unit of light visible to the human eye. Luminosity then is the measure of lumens reflecting from (or transmitted through) a light source and perceived by your eye. The more lumens, the brighter the light. Light measurements are also made in increments called candelas. A candela is roughly the value of light produced by a single household candle.

Photo by Akshay Paatil on Unsplash

Just as “horsepower” is a carryover index of a measurement of power (relating to the pulling strength of multiple horses) candelas is an index of the cumulative light emitted from multiple candles. These legacy terms are sometimes confusing, and it would be nice if photographic color science terminology were simplified for those just entering the process, but until then, you’ll have to get acclimated.

I’ll take it slow, as you can easily drown in the scientific terminology minutia. I’ll keep the terminology on a basic digital imaging level so that you can make practical use of what you learn.

Basic Color Science

Ryb-colorwheel

As stated before, all color is composed of three elements; value, intensity, and luminosity. Value (or hue) refers to the “color” of color, or what differentiates red from orange or purple. Intensity (or saturation) refers to the purity color, distinguishing pastels to pungent colors (the more white light is combined with pure color, the more the color strength is diluted). Luminosity is the measure of the brightness and relates to the image’s lightness or darkness.

Hue (value) differentiates one color from another. Saturation (intensity) determines the purity of color. Luminosity (brightness) determines tonality.

The detail in digital imaging terminology is the degree to which colors and tones distinguish themselves from each other. While hue, saturation, and luminance all play a significant role in detailing an image, the heavy lifting of detail is done by luminance or the shaping of the internal tones in an image. Detail is a product of contrast, and contrast is almost completely controlled by the luminance element. This is why post-production professionals perform all their sharpening adjustments in the luminance channel exclusively.

Shadows Highlights dialog - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

Photoshop’s Highlight/Shadow dialog box

Camera Raw dialog - How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

Adobe Camera Raw main dialog.

Shaping Light

Contrast, like audio equalization, cannot be effectively accomplished by using a linear (bass-treble) type control such is the luminance slider in the HSL panel which simply lightens or darkens an image. The effective shaping of an image requires the individual adjustment of five specific tonal regions of an image; highlight, quarter-tone, mid-tone, three-quarter tone and shadow. I use a variety of controls to shape my tonal contrast.

Ansel Adams once stated, “Half the image is created in the camera, the other half is created in the darkroom.” Though you may never use a darkroom to produce a photographic image, the essence of his statement is still true. Capturing pixels with your camera is only your first step in producing a good picture, what you do with the image that comes out of your camera will determine your skills as a photographer.

Digital photography provides almost limitless avenues for personal expression. Shaping the color and tonality in your images is the backbone of great photography. Determine to learn something new about this fabulous art form every day. Push pixels around and stay focused.

The post How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality by Herb Paynter appeared first on Digital Photography School.


Digital Photography School

 
Comments Off on How to Understand the Science of Photography and Technical Terms for Mastering Image Tonality

Posted in Photography

 

Instagram terms and conditions rewritten in simple language for teens

10 Jan

Law firm Schillings was recently tapped by the UK’s Children’s Commission to rewrite Instagram’s Terms and Conditions in simplified, child-friendly language. The simplified terms of service were included in the Commission’s newly published ‘Growing Up Digital’ report detailing, among other things, ways in which the Internet can help young users become better informed about the websites and apps they use.

At the heart of the report is a concern that children (and many adults) are unable to make informed decisions about the digital services they use due to the difficulty of understanding a service’s terms and conditions. The report cites Instagram’s Terms and Conditions as one example, finding that it contains 5,000 words across 17 pages ‘with language and sentence structure only a postgraduate could be expected to understand.’

Teenagers tasked with reading original Instagram Terms and Conditions report trouble understanding the information and frustration at its length. When given the rewritten TAC, however, which are condensed down to only a couple pages, the teenagers are able to explain the rules, what rights they have, and what rights Instagram reserves.

The full rewritten Instagram Terms and Conditions can be found on page 10 of the Commission’s report.

Via: PetaPixel

Articles: Digital Photography Review (dpreview.com)

 
Comments Off on Instagram terms and conditions rewritten in simple language for teens

Posted in Uncategorized

 

Instagram backs away from controversial changes to terms of service

19 Dec

Istagram_logo.png

Instagram has backed away from controversial changes it planned to make to its terms of service. Co-founder Kevin Systrom has used the company blog to announce that the most sensitive phrase in the terms will be revised. The update would have given Instagram the right to sell user’s images to third parties without compensating them. Systrom says this was never the company’s intention. Instead, he says, wording will be developed to allow it to associate information such as users’ profile images with commercial postings (as Instagram’s owners, Facebook, do).

News: Digital Photography Review (dpreview.com)

 
Comments Off on Instagram backs away from controversial changes to terms of service

Posted in Uncategorized

 

What you need to know: Instagram’s new terms of service

18 Dec

Instagram_Icon_Large.png

Photo-sharing service Instagram is making headlines for a change to its terms and conditions that appears to allow the sale of users’ images. According to the updated terms of service, Instagram users ‘agree that a business or other entity may pay us to display your username, likeness, photos (along with any associated metadata), and/or actions you take, in connection with paid or sponsored content or promotions, without any compensation to you’. Understandably, some Instagram users are very unhappy, but do they need to be? Click through to read our quick guide to what the new terms and conditions mean for you. 

News: Digital Photography Review (dpreview.com)

 
Comments Off on What you need to know: Instagram’s new terms of service

Posted in Uncategorized

 

Photographers Upset By Instagram’s Change in Terms of Service

18 Dec

Earlier today Instagram announced that they are changing their Terms of Service effective January 13th 2013.

The most controversial part of the change is outlined below:

“To help us deliver interesting paid or sponsored content or promotions, you agree that a business or other entity may pay us to display your username, likeness, photos (along with any associated metadata), and/or actions you take, in connection with paid or sponsored content or promotions, without any compensation to you.”

Now I have no idea if Instagram actually plans on selling/licensing your photos or not — sometimes the lawyers get a hold of things like this and push the envelope too far with a TOS — but this change seems to go further to me than the typical giving up of rights to your photos for typical social media display purposes.

Facebook’s TOS by contrast reads:

“For content that is covered by intellectual property rights, like photos and videos (IP content), you specifically give us the following permission, subject to your privacy and application settings: you grant us a non-exclusive, transferable, sub-licensable, royalty-free, worldwide license to use any IP content that you post on or in connection with Facebook (IP License). This IP License ends when you delete your IP content or your account unless your content has been shared with others, and they have not deleted it.”

While this appears functionally similar to Instagram’s, Facebook doesn’t actually mention so specifically the idea of selling your content and you getting zero compensation.

Google+’s TOS tends to provide photographers greater protection with a provision that your content there can be used for the “limited purpose of operating, promoting and improving our services, and to develop new ones.” Nothing about selling off your photos to third parties there, folks.

“When you upload or otherwise submit content to our Services, you give Google (and those we work with) a worldwide license to use, host, store, reproduce, modify, create derivative works (such as those resulting from translations, adaptations or other changes we make so that your content works better with our Services), communicate, publish, publicly perform, publicly display and distribute such content. The rights you grant in this license are for the limited purpose of operating, promoting, and improving our Services, and to develop new ones.”

Flickr takes it even one step further actually dedicating a specific blog post to this issue last year titled “At Flickr Your Photos are Always Yours.”

This change today has upset a lot of photographers and content creators. The New York Times takes apart the new TOS here. Blogger Robert Wagner puts his view more succinctly in a blog post titled Goodbye Instagram and f*** you.

Personally speaking, I trust that Google will not sell my photos out from underneath me. I think their TOS is pretty clear about their limited scope of use. I applaud Flickr for taking it one step further with a blog post spelling out that you always own your photos on Flickr. Interestingly enough, even before this announcement I saw my first “I’m leaving you Instagram for Flickr” post this past weekend.

Wired has a post that shows you how to take your photos off of Instagram and delete your account.

Gizmodo seems to take a different view of this situation, calling folks concerned with today’s announcement whiny little babies.

What are your thoughts? Will you continue to use Instagram? Are photographers overreacting here?

My own view is that I think Instagram is pushing it a little too far with this one. I think I’d rather pay them a subscription fee like I pay Flickr than have them out there selling my photos.


Thomas Hawk Digital Connection

 
Comments Off on Photographers Upset By Instagram’s Change in Terms of Service

Posted in Photography

 

What is HDR and Aperture and Stuff? 30 Photo Terms You Must Know Letter-Perfect

29 Nov

Falling in love with photography is easy. Being scared away by the highbrow photo terms is even easier. Crop-factor, aperture, depth of field… What the heck?! Come on, it is not that complicated, you just need a minute to settle it all down, step by step. Here’s a rundown in plain English of the most common terms you’ll hear or Continue Reading

The post What is HDR and Aperture and Stuff? 30 Photo Terms You Must Know Letter-Perfect appeared first on Photodoto.


Photodoto

 
Comments Off on What is HDR and Aperture and Stuff? 30 Photo Terms You Must Know Letter-Perfect

Posted in Photography