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Posts Tagged ‘zoom’

Have your say: Best zoom lens of 2017

17 Dec

This year saw plenty of new lenses released, including several excellent zooms. We’ve used a lot of them, but we want to hear from you – what were your favorite zoom lenses of 2017?

Articles: Digital Photography Review (dpreview.com)

 
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2017 Buying Guide: Best enthusiast long zoom cameras

06 Dec

Long-zoom compacts fill the gap between pocketable cameras and interchangeable lens models with expensive lenses, offering a great combination of lens reach and portability. Here’s a look at the category’s current offerings and which ones we like best.

Articles: Digital Photography Review (dpreview.com)

 
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Review of the Tamron 18-400mm F/3.5-6.3 DI-II VC HLD Zoom Lens

22 Nov

Tamron has been specializing in super-zoom lenses for the last few years. You may be familiar with their 16-300mm, 18-270mm or 150-600mm lenses. Their newest super-zoom is an even more astonishing focal length, the Tamron 18-400mm. I recently had a chance to review this lens for a few weeks so I thought I’d give you an idea of who this lens is for, the good, the not-so-good, and my overall recommendation.

Review of Tamron 18-400mm F/3.5-6.3 DI-II VC HLD Zoom Lens - Hibiscus

Hot pink hardy hibiscus bloom. Canon 7D Mark II, Tamron 18-400mm lens @ 400mm, f/9, 1/160th, ISO 100, handheld.

About this review

I know you already know this (because you read ALL my pieces for dPS, right? Right?!) but my lens reviews are pretty real world. I don’t sit in a lab or use techy gizmos to measure sharpness. I actually hold a lens in my hands and shoot with it. This lens was tucked in my favorite bag for most of August.

That said, my intention was to see how a lens holds up for an actual shoot. I used this lens to photograph Lipizzan horses at a dressage performance as well as at the racetrack. Then I used it on a mission to photograph old barns and finally to make some macro flower images.

Tamron 18-400mm lens -  Lipizzan Foal

Lipizzan foal at Tempel Farms, Old Mill Creek IL. Canon 7D Mark II, Tamron 18-400mm lens @ 300mm, f/6.3, 1/640th, ISO 500, handheld. 

The goal was to make images at most focal lengths with a variety of apertures, but a few might have been skipped because I was really out there shooting. I shoot at the focal length, shutter speed, ISO and aperture that each situation calls for. So let’s just say I apologize in advance if I’ve skipped something important to you. Give me a shout in the comments if that’s the case. I’ll dig through my notes and image archives to see if I can answer your question.

Lens specs

Let’s start off with a quick overview of the lens specs. This lens is for Nikon and Canon APS-C (crop sensor) cameras only. I tested the lens on a Canon 7D Mark II.

The Tamron 18-400mm super-zoom is a variable aperture lens. Meaning that at 18mm, the maximum aperture (largest opening) is f/3.5. But when you zoom into 400mm, the maximum aperture is f/6.3. The minimum aperture (smallest opening) is f/22 at all focal lengths.

Tamron 18-400mm - Red barn

Dilapidated red barn, McHenry County IL. Canon 7D Mark II, Tamron 18-400mm lens @ 71mm, f/9, 1/250th, ISO 200, handheld.

The lens has an HLD Autofocus Motor that is quick and quiet for a consumer lens at this price. It also has Tamron’s standard VC Image Stabilization. This feature enables you to get sharper shots while hand-holding at longer focal lengths. The lens also has what Tamron calls Moisture-Resistant Construction. I’m relieved to tell you I didn’t get to test this feature.

The minimum focusing distance – important especially if you want to try your hand at making macro images – is 17.72″ (45 cm). Macro is usually a 1:1 ratio and this lens only produces 1:2.9, but I was pleasantly surprised with my macro results.

Tamron 18-400mm - White bud

White hardy hibiscus bud. Canon 7D Mark II, Tamron 18-400mm lens @ 400mm, f/13, 1/320th, ISO 320, handheld.

If you use screw on filters, like a circular polarizer, the front thread is 72mm. The lens is 1.56 pounds (710 g) and approximately 3.11” in diameter by 4.88″ in length (79 x 123.9 mm). It’s an incredibly compact lens for this focal length range.

The price, at the time of publication of this article, is $ 649.00 USD.

Who is this lens for?

I would describe the ideal user of this lens as an amateur or enthusiast. If you’re an amateur photographer who travels but doesn’t want to carry more than one or two lenses, this is the perfect choice for you.

With an 18-400mm focal length, you might not need to ever change the lens, except in a dark indoor situation, when you need either flash or perhaps the fast f/1.8 maximum aperture of a nifty fifty.

Tamron 18-400mm - racehorse portrait

Low-key portrait of a racehorse, Arlington Park IL. Canon 7D Mark II, Tamron 18-400mm lens @ 400mm, f/6.3, 1/250th, ISO 250, handheld.

This lens would also be great for a busy parent who needs more than a smart phone to capture pictures of soccer matches and dance recitals but who doesn’t have a ton of extra room in her carryall bag. The compact size and weight of the Tamron 18-400mm make it an easy addition to any parent’s standard kit.

What’s good about this lens

The size of this lens just can’t be beat. At only a pound and a half and less than 5 inches long, it’s a lot of focal length in a very small package. I was really taken with how small it was since I normally shoot with such large neck-and-shoulder-busting glass.

Hand-holding this lens for an afternoon at the race track wasn’t even remotely painful. With the insane focal length capabilities, I didn’t even bother to carry a second lens with me (or even my camera bag!) and that made for a really care-free afternoon.

Tamron 18-400mm - size comparison

The Tamron 18-400mm lens, attached to the Canon 7D Mark II, with the Canon 100-400 lens alongside for size comparison.

Tamron 18-400mm lens comparison - extended

The extended Tamron 18-400 lens, attached to the Canon 7D Mark II, with the extended Canon 100-400 lens alongside for size comparison. Clearly you can see what a compact size this lens is and how beneficial that could be when you travel.

Great for landscape images

It’s also a pleasure to catch a pretty landscape out of the corner of your eye and to simply zoom out to 18mm to capture it. Typically if you’re shooting with a long lens, you have to take the time to switch over to your wide-angle lens, take the shot and then switch back to your longer focal length lens again. Well, actually, if you’re me, you see that landscape and think ooh, pretty and then walk away without taking the shot.

Tamron 18-400 - at the track

Arlington Park Racetrack IL. Canon 7D Mark II, Tamron 18-400 @ 18mm, f/13, 1/100th, ISO 320, handheld. Processed in Lightroom.

I’m lazy that way so this was the first time I’ve actually made images of the racetrack itself. The lens performed really well in the 18-50mm focal range. It was both sharp and relatively distortion free. Lightroom’s Lens Correction easily managed the slight distortion there was too.

Things to be careful of

Remember I said we’d talk about the not-so-good too? It is a touch tricky to twist the lens in order to zoom in past 200mm to get to the 400mm focal length. First, your hand gets a bit “stuck” since anatomically, your wrist only twists so far before you have to reposition in order to continue the twisting motion.

Tamron 18-400mm lens - racetrack

Headed to the gate, Arlington Park IL. Canon 7D Mark II, Tamron 18-400mm lens @ 209mm, f/6.3, 1/1000th, ISO 250, handheld. 

Second, the lens has what I call a “hiccup” where you need to exert more pressure to push it past this point. I missed a few shots because the twisting motion wasn’t smooth enough and I jerked the lens a bit as I zoomed in from 200mm to 400mm.

Tamron 18-400mm lens - white hibiscus

White hardy hibiscus bloom. Canon 7D Mark II, Tamron 18-400mm lens @ 227mm, f/13, 1/400th, ISO 320, handheld.

Softness around the edges

There is a definite softness (or loss of sharpness) at the longer end of the lens, especially when your aperture is wide open, e.g., 400mm at f/6.3. If you crop in too much during post-processing or print too large, you’ll start to see the loss of fine details in your image since they weren’t tack sharp to start. You won’t see this loss of detail in a small 5×7″ print, or if you post to social media – so for many people, this actually won’t be a big issue.

Tamron 18-400mm lens Review - Riders up

Riders up at the paddock, Arlington Park IL. Canon 7D Mark II, Tamron 18-400mm lens @ 18mm, f/5, 1/500th, ISO 640, handheld.

Use the center focus point

The lens tends to be softest in the corners so sharpness improves if you use your camera’s center focus point. It also improves if you close down your aperture to f/8, f/9, or smaller. Because the lens is not tack sharp all the way through the focal length spectrum, I’m not recommending this lens for super serious wildlife shooters or anyone who likes to print really large. For you guys, I’m going to suggest sticking with a more standard zoom lens like a 100-400mm or 200-400mm. (I apologize in advance for the wear and tear this recommendation will cause your shoulders.)

If you predominantly shoot wide-angle images, like landscapes, and only occasionally shoot long, this lens will be a good fit for you when you don’t want to carry a ton of gear.

Final thoughts

Ultimately there were a number of things I really liked about this lens. The small size and super-zoom focal length make it a very practical tool to have in your bag. At $ 649.00 USD, it’s also a great value.

However, the softness at the long end of that focal length can become a real issue if you’re not careful. Because of that, I’m cautiously going to rate this lens 3.5 stars out of 5.

Tamron 18-400mm lens running foal

Running Lipizzan foal at Tempel Farms, Old Mill Creek IL. Canon 7D Mark II, Tamron 18-400mm lens @ 400mm, f/6.3, 1/640th, ISO 100, handheld. 

I’d love to hear your opinions too. Have you tried super-zooms lenses? Do they work for your type of photography? Which is your favorite one and how does it compare to the Tamron 100-400mm lens? Please share your thoughts with the dPS community in the comments below.

The post Review of the Tamron 18-400mm F/3.5-6.3 DI-II VC HLD Zoom Lens by Lara Joy Brynildssen appeared first on Digital Photography School.


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Corephotonics sues Apple over dual-camera zoom patents

08 Nov

Israel-based company Corephotonics—which is best known for its smartphone dual-camera systems—has filed a patent infringement case against Apple in federal court. The company claims that has used Corephotonics’ dual-camera zoom technology in the iPhone 7 Plus and 8 Plus without authorization.

According to the complaint, Corephotonics Chief Executive David Mendlovic had attempted to negotiate a partnership with Apple. However, while Corephotonics received positive feedback on their technology from Apple, the iPhone makers refused a licensing deal, suggesting Corephotonics patents could be infringed with little consequence.

From the lawsuit:

As one of its first acts as a company, Corephotonics reached out to Apple in the hopes of establishing a strategic partnership. Corephotonics received many encouraging reports and positive feedback from Apple about its technology, but the parties never concluded a license to the Corephotonics technology.

In fact, after one failed effort to negotiate a license, Apple’s lead negotiator expressed contempt for Corephotonics’ patents, telling Dr. Mendlovic and others that even if Apple infringed, it would take years and millions of dollars in litigation before Apple might have to pay something.

Corephotonics investors include Foxconn and chipmaker MediaTek, which are both suppliers to Apple. In the lawsuit the company is represented by legal firm Quinn Emanuel Urquhart & Sullivan, which also advised Samsung Electronics on its patent litigation with Apple.

Articles: Digital Photography Review (dpreview.com)

 
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Tamron unveils lightweight 100-400mm F4.5-6.3 ultra-telephoto zoom for $800

29 Oct

Tamron just revealed its newest ultra-telephoto zoom. Meet the Tamron 100-400mm F4.5-6.3 Di VC USD (Model A035) for full-frame Canon and Nikon DSLRs—a lens that combines compact, lightweight construction with ‘superior’ image quality and ‘fast and precise AF’, according to Tamron. The lens’ tagline: heavyweight performance in a lightweight lens.

The new lens was revealed this morning, and its claim to fame is its size and weight. At just 39.3 oz., the new 100-400mm lens is the lightest in its class thanks to the use of magnesium allow in ‘key areas’ of the lens barrel. Inside that barrel you’ll find 17 lens elements in 11 groups—including three low dispersion (LD) elements—and Tamron’s high-speed Dual MPU that allows for ‘fast and precise AF’ as well as four stops of stabilization.

Below are some sample photos captured with the new Tamron 100-400 F4.5-6.3 Di VC USD at the racetrack by photographer Takahito Mizutani for Tamron:

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The Tamron 100-400mm F4.5-6.3 Di VC USD will be available starting November 16th, in both Canon and Nikon mounts, for $ 800. To find out more or see more impressive sample photos, read the full press release below or head over to the Tamron website.

Press Release

100-400mm F/4.5-6.3 Di VC USD (Model A035)

Tamron announces the launch of a new ultra-telephoto zoom lens with fast and precise AF, superior image quality and a lightweight, compact design

October 26, 2017, Commack, New York— Tamron USA, Inc. , announces the launch of a new ultra-telephoto zoom lens, 100-400mm F/4.5-6.3 Di VC USD (Model A035), for full-frame Canon and Nikon DSLR cameras. The Model A035 delivers fast and precise AF performance and consistently powerful VC (Vibration Compensation) 4 stops*1 benefits thanks to the high-speed Dual MPU (Micro-Processing Unit) control system that is found in the latest Tamron lens models. The advanced optical design of Model A035 includes three LD (Low Dispersion) lens elements for aberration reduction and Tamron’s original eBAND Coating for superior anti-reflection performance. At 1,115g (39.3 oz), the new lens is the lightest in its class*2 and features magnesium alloy in key areas of the lens barrel to ensure weight reduction, and improve strength and portability. Model A035 is compatible with Tamron’s 1.4X tele converter and the Tamron TAP-in ConsoleTM that enables lens customizations for focus adjustments, VC mechanism adjustments and more. Additionally, an Arca Swiss compatible tripod mount is available as an optional accessory. The new Tamron 100-400mm will be available in both Canon and Nikon mounts on November 16th at $ 799.

PRODUCT HIGHLIGHTS

1. High-speed Dual MPU (Micro-Processing Unit) control system delivers quick and highly responsive autofocus performance plus outstanding VC image stabilization

The Dual MPU system includes an MPU dedicated to vibration compensation processing, enhancing the computational capacity of the entire system. An MPU with built-in DSP (Digital Signal Processor) provides high-speed digital signal processing and achieves outstanding autofocus performance and vibration compensation, both indispensable for ultra-telephoto photography.

2. Superb image quality in an ultra-telephoto zoom lens

The Model A035 includes three LD (Low Dispersion) lens elements for optimal optical design and aberration correction. Lighter weight, increased light transmission and crisp images with excellent contrast are achieved by reducing the number of lens elements while ensuring an appropriate balance with aberration correction. The A035 has minimum object distance (MOD) of 1.5 m (59 in) and a maximum magnification ratio of 1:3.6 for close-up work.

3. Exclusive eBAND Coating reduces flare and ghosting

The new A035 features Tamron’s eBAND (Extended Bandwidth & Angular-Dependency) Coating, which has an extremely low refractive index and fine multiple-layer coating technology, to achieve outstanding antireflection performance. BBAR (Broad-Band Anti-Reflection) Coating, with excellent antireflection characteristics, increases light transmission. These coating technologies greatly reduce the ghosting and flare that can occur when subjects are backlit.

4. Lightest weight, 1,115 g (39.3 oz) lens in the ultra-telephoto zoom lens class*, and only 196.5 mm (7.7 in) long

Magnesium alloy is used in key areas of the lens barrel to improve weight reduction, strength and portability. Total length of 196.5 mm (Nikon mount) means a compact size for an ultra-telephoto zoom lens covering up to 400 mm, and the A035 can therefore be easily carried in a standard camera bag. Combined with excellent vibration compensation functions, the compact size enables successful handheld ultra-telephoto photography.

*Length is the distance from the front tip of the lens to the lens mount face.

5. Optional accessory tripod mount is Arca-Swiss compatible

An Arca-Swiss style tripod mount is available as an optional accessory. Designed exclusively for Model A035, it provides quick and secure attachment to a tripod and greater stability. An easy-to-hold grip shape includes an expanded mounting plane, and the use of magnesium helps achieve lighter weight, thereby further facilitating handheld photography.

6. Compatible with tele converters and TAP-in Console

Model A035 is compatible with tele converters designed exclusively for Tamron lenses to achieve 1.4X and 2X the original focal length*. It’s also compatible with Tamron’s TAP-in Console (Model TAP-01), an optional accessory enabling users to update lens firmware and customize the lens settings, including adjustments of focusing positions for autofocusing and the operation modes for the lens’s Vibration Compensation system.

*Use of the 1.4× tele converter results in light reduction of 1 F stop; use of the 2× tele converter results in the loss of 2 F stops

7. Moisture-Resistant construction and fluorine coating for enhanced weather protection

The surface of the front element is coated with a protective fluorine compound that has excellent water- and oil-repellant qualities. The front surface is easier to wipe clean and is less vulnerable to the damaging effects of dirt, dust, moisture or oily fingerprints, allowing for much easier maintenance. Also, with active use of the A035 for outdoor photography likely, sealant is used in each of the movable and joining areas of the lens barrel to resist the intrusion of moisture.

8. Electromagnetic diaphragm system now used also for Nikon-mount lenses

An electromagnetic diaphragm system, which has been a standard feature for Canon-mount lenses, is now employed in Nikon-mount lenses*. More precise diaphragm and aperture control is possible because the diaphragm blades are driven and controlled by a built-in motor through electronic pulse signals.

* Available only with cameras compatible with the electromagnetic diaphragm (D5, D4s, D4, D3X, Df, D850?D810, D810A, D800, D800E, D750, D600, D610, D300S, D500, D7500, D7200, D7100, D7000, D5600, D5500, D5300, D5200, D5100, D5000, D3400, D3300, D3200, D3100). (As of October, 2017; Tamron)

9. External design places importance on functionality and ease of use

While inheriting the design that makes use of many organic curves and the delicately polished form down to fine details that characterize the SP lens series, the new Model A035 comes with a highly sophisticated design that also places a lot of importance on the lens’s functionality and ease of use, featuring an overall form that faithfully encompasses the internal structures within, a slim Luminous Gold brand ring and the switch shape design.

Tamron 100-400mm F4.5-6.3 Di VC USD specifications

Principal specifications
Lens type Zoom lens
Max Format size 35mm FF
Focal length 100–400 mm
Image stabilization Yes
CIPA Image stabilization rating 4 stop(s)
Lens mount Canon EF, Nikon F (FX)
Aperture
Maximum aperture F4.5–6.3
Minimum aperture F32–45
Aperture ring No
Number of diaphragm blades 9
Optics
Elements 17
Groups 11
Special elements / coatings Three LD elements + eBAND coating
Focus
Minimum focus 1.50 m (59.06)
Maximum magnification 0.28×
Autofocus Yes
Motor type Ring-type ultrasonic
Full time manual Yes
Focus method Extending front
Distance scale Yes
DoF scale No
Physical
Weight 1135 g (2.50 lb)
Diameter 86 mm (3.39)
Length 199 mm (7.83)
Materials Magnesium alloy
Sealing Yes
Colour Black
Zoom method Rotary (extending)
Filter thread 67.0 mm
Hood supplied Yes
Tripod collar No
Optional accessories Tripod collar

Articles: Digital Photography Review (dpreview.com)

 
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The clockwork lens: Lensrentals tears down famed Minolta 40-80mm F2.8 Gearbox Zoom

27 Sep

Lensrentals tears down famed Minolta 40-80mm F2.8 Gearbox Zoom

Photograph by Tom Leonard

The Minolta MC Rokkor X 40-80mm F2.8 zoom is a unique lens, which uses a gearbox for controlling focus and zoom. The advantage of this design? It’s pretty small for an F2.8 zoom, especially one made in the 70’s, and more precise than a conventional helicoid. The downside? It’s fiendishly hard to take apart – as Roger Cicala and Aaron Closz at Lensrentals recently found out…

Lensrentals tears down famed Minolta 40-80mm F2.8 Gearbox Zoom

Image courtesy of Lensrentals

Roger and his team started by removing parts of the rear lens assembly, including the aperture ring. So far, so conventional. In Roger’s words: “We were starting to feel a little confident now. That confidence, as you will see, was entirely misplaced.”

Lensrentals tears down famed Minolta 40-80mm F2.8 Gearbox Zoom

Image courtesy of Lensrentals

Removing the leatherette that covers the lens barrel revealed several screws which – once unscrewed – allowed the gearbox housing to be removed, revealing the complicated mechanism for controlling zoom and focus.

Lensrentals tears down famed Minolta 40-80mm F2.8 Gearbox Zoom

Image courtesy of Lensrentals

Inside the housing, you can see the macro selection and focusing mechanisms, both of which move what Roger is calling ‘The Magic Slot’ (indicated with a red arrow). If this looks complicated, that’s because it is. In Roger’s words, “this is a mechanical art of the highest order”, ensuring that even when the lens is zoomed, the focus point remains unchanged. That was impressive stuff for the 1970’s (and even today).

Lensrentals tears down famed Minolta 40-80mm F2.8 Gearbox Zoom

Image courtesy of Lensrentals

Back to the lens barrel, and things are getting even more complicated…

Here, the green arrow is pointing to the zoom stem, while the red arrow indicates a heavy duty brass post covered with a white bumper. Since “normal lens terms like helicoid and cam don’t work here” Roger is calling this ‘The Golden Post’.

Lensrentals tears down famed Minolta 40-80mm F2.8 Gearbox Zoom

Image courtesy of Lensrentals

For a full explanation of exactly how all of this works, we’d recommend heading over to Roger’s original blog post, which explains things in fascinating detail. In the meantime, here’s a picture of the mechanical zoom and focus assembly, removed from the lens barrel.

Lensrentals tears down famed Minolta 40-80mm F2.8 Gearbox Zoom

Image courtesy of Lensrentals

With this assembly removed, the 40-80mm starts to look rather more like a conventional lens. To completely disassemble it, though, the team referred to ‘Aaron’s Second Rule of Disassembly’. Specifically – All leatherette must be removed. Because underneath leatherette, you’ll invariably find screws.

Lensrentals tears down famed Minolta 40-80mm F2.8 Gearbox Zoom

Image courtesy of Lensrentals

Finally, after “about an hour of time and a thorough and complete use of our full lexicon of unprintable words”, Roger and Aaron managed to get the inner barrel out of the outer casing.

Lensrentals tears down famed Minolta 40-80mm F2.8 Gearbox Zoom

Image courtesy of Lensrentals

With the front optics taken out, the aperture blades were revealed. After such a complex disassembly, Roger and Aaron “were glad to see something that looked familiar”.

Lensrentals tears down famed Minolta 40-80mm F2.8 Gearbox Zoom

Image courtesy of Lensrentals

And here is the 40-80mm F2.8, reduced (almost) to its component parts. Roger’s final takeaway, from one of the most complex disassemblies he’s ever done?

“There were some slick engineers working on things at Minolta back in the 1970s, thinking way outside the box”.

If this article whetted your appetite, we’d encourage you to head to Lensrentals for a full explanation of the entire process (including MTF charts!) and read more about the unique 40-80mm F2.8 in Tom Leonard’s article, ‘A forgotten solution: Why this strange 1975 zoom lens is so sharp’. See links below.

Read the full article on Lensrentals.com

Read Tom Leonard’s writeup of the Minolta MC Rokkor-X 40-80mm F2.8

Articles: Digital Photography Review (dpreview.com)

 
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Take Your Photography into Hyperdrive with Zoom Blur Photos

26 Sep

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DxOMark Mobile testing protocol now considers bokeh simulation, low-light, motion and zoom

12 Sep

Camera and lens testing company DxOMark has announced an updated smartphone camera evaluation protocol that evaluates additional elements encompassing some of the newer mobile camera technologies. This new protocol builds upon the previous version, adding an updated low-light test that evaluates performance down to 1 lux, new bokeh and zoom tests, and a motion-based test.

DxOMark detailed the new mobile protocol on Monday, explaining that it is better capable of evaluating phones packing the newest mobile camera capabilities, particularly ones made possible by dual-camera hardware. The company has re-tested some top-tier phone models under the new protocol, finding that in some cases scores increased when looking at features like low-light performance, bokeh, and zoom.

A detailed analysis of the new protocol versus the old protocol sheds some light on what DxOMark is looking for in these new categories, as well as charting the score changes some phones experienced under the new protocol. The company also offers a more in-depth look at the new protocol in a blog post.

Via: Digital Trends

Articles: Digital Photography Review (dpreview.com)

 
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Asus ZenFone 4 Pro dual-cam comes with 2x zoom and portrait blur

18 Aug

Taiwanese manufacturer Asus is a pioneer in the area of smartphone zoom, and so it does not come as a surprise that its latest flagship model, the ZenFone 4 Pro, comes with a quite impressive looking dual-camera setup that offers 2x zoom capability.

The main sensor in the dual-camera is a 12MP 1/2.55″ Sony IMX362 that comes with large 1.4um pixels and sees the world through a fast F1.7 aperture and 4-axis optical image stabilization. In terms of autofocus, Asus bundles PDAF with laser-based time-of-flight technology for reliable performance in all light conditions.

The main camera also comes with a manual mode that allows for up to 32 second shutter speeds, and 120 fps slow-motion video at 1080p resolution in addition to a 4K mode. Finally, a super-resolution mode can create 48MP images out of four 12MP captures.

The secondary camera uses a smaller Sony IMX351 sensor with 1um pixels and a slower F2.6 aperture. The camera offers both 2x optical zoom and a background-blurring bokeh-effect, but the smaller sensor and a lack of OIS and PDAF in the tele-module probably means those modes are best reserved for bright-light shooting.

In the front camera you’ll find an 8MP Sony chip with 1.4um pixels and an F1.9 aperture, alongside other flagship-worthy specifications: the Android OS is powered by a Snapdragon 835 chipset, images can be viewed on a 5.5″ 1080p AMOLED display, and the phone is wrapped up in a glass-metal-glass sandwich design body.

Prices for the ZenFone 4 Pro start at $ 600.

Key Specifications:

  • Dual-cam with 2x zoom
  • Main camera with 12MP 1/2.55″ Sony IMX362 sensor, F1.7 aperture and 4-axis OIS
  • PDAF and laser AF
  • 4K video, 1080p slow-motion at 120 fps
  • Tele camera with Sony IMX351 sensor with 1um pixels and F2.6 aperture
  • 8MP / F1.9 front camera
  • Snapdragon 835 chipset
  • 5.5″ 1080p AMOLED display
  • up to 6GB RAM
  • up to 128GB internal storage
  • microSD support

Articles: Digital Photography Review (dpreview.com)

 
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A forgotten solution: Why this strange 1975 zoom lens is so sharp

15 Aug

For a few years now, I’ve had in my collection one very strange lens. I bought it primarily for it’s value as a collectible so, up until now, I haven’t really spent much time playing with it.

Made in 1975, this manual focus Minolta MC Rokkor-X 40-80mm F2.8 lens is one strange puppy. When it was first introduced, no other zoom lens could top its image quality and it really didn’t have much competition until more recent years. This is largely due to its very unique Gearbox design that sought to overcome the problem with zoom lenses that we still face today.

Way back in 1959, the first commercially-available 35mm still camera zoom lens, the Bessematic-mount Zoomar 36-82mm F2.8, was released by Voightlander. It’s mechanical design would not be unfamiliar to you since the focus and focal length were adjusted via a few round-turns of the lens barrel.

This simple helicoid design remains the only common method manufacturers use to make our lenses zoom in and out and focus. When you twist the zoom/focus ring(s) of a lens, the optics are carried forward or backward through a threaded barrel. This design results in a fixed movement ratio of the optical groups mounted inside that helicoid. The problem with this is every focal length requires a slightly different adjustment of the lens element/group spacing to properly correct aberrations and the fixed ratio of a helicoid cannot provide that kind of variance.

The helicoid is relatively simple, easy to make, and its shape tailors to a fitting physical design of a lens. If a lens were designed to have as few compromises as possible, it might look vastly different from what we see sitting on store shelves. For simplicity though, manufacturers have stuck with the helicoid and instead invested in overcoming its mechanical shortfalls with optical solutions.

Over the years, lens designers, aided by computers, have learned how to improve the optical designs of the zoom lens to work around most of the limitations of the locked-ratio helicoid. Modern zooms still aren’t quite as good as a prime lens but, with aspherical lens elements and fancy coatings to help out, they’re getting pretty darn close.

Back in the early 1970’s, Minolta’s engineers, armed with their slide rules and cigarettes, had a go at thinking outside the box to come up with a lens design that would allow for precise positioning of the optical groups in a zoom lens. What they came up with was so clever that it required they put it inside a box—a gearbox, to be precise.

Rather than work with the limitations of a helicoid design, this clever bunch decided to abandon that whole concept and create a new one where lens groups would be blessed with the freedom to move independent of each other. They came up with this unorthodox gearbox design that drives 12 optical elements in 12 separate groups along linear, gear-operated rails. With the chains of fixed-ratio movement cast from them, the entire lens design could be “geared” for precise positioning of the optics to best correct for aberrations throughout the range of focal lengths.

What they did was figure out how to make a hand held zoom lens that is as well corrected across its range of focal lengths as a fixed focal length lens would be at its one—that’s the theory anyway. In spite of the weird and wart-like appearance of their solution, Minolta’s engineers achieved with this lens something that is truly unique and special. There is no mistaking this lens for any other, that’s for sure.

Weighing in at 19.75 ounces (560 g), it isn’t particularly big or heavy. In fact, even with all the metal machinery inside this lens, it’s almost exactly half the weight of Nikon’s current 24-70mm f/2.8 VR.

Focus is adjusted by turning the big wheel while focal length is controlled by moving the lever arm. Both controls are very smooth and easy to move across their fairly short range of motion. The focus wheel features a precise distance scale with Infrared Index.

The lens has a 55mm diameter coated front element. Here you can see the profile of the gearbox which is fixed to the left-hand side of the lens body.

Did I mention it has a macro mode? The lens has a metal stem poking out of the gearbox which, when twisted anti-clockwise and pushed in, shifts everything inside the lens out toward the front, essentially putting more space between the film/sensor plane and the rear element (same thing an extension tube does). The result of this forward-shift is a reduction in the Minimum Focal Distance from 3.3 ft (1.01 m) to 1.2 ft (.37 m) @40mm.

Here, the stem is shown in the Macro position. When pushing in this stem, the focal length lever shifts forward with the internal glass. What a cool, whacky design!

Let’s see how well all of the engineering effort translates into actually making images with this lens.

My sister told me about this row of old silos that sit alongside a two-lane road not too far from where I live. Yesterday, I had to go by it while I was on errands. On the return trip I pulled over for this shot.

I had the lens set to 40mm and the aperture was wide-open at F2.8. This was the first shot I took and I kind of hurriedly grabbed it because of the unique lighting. That isn’t vignetting in the grass. Passing over head was a thick, dark cloud that cast the strangest light over this scene. No sooner I had shot this and the sun was back out in the open.

On the same errand run, I came across this old Chevrolet police car. Focal length was 80mm @ F8.

I was very interested to see how well the lens would control chromatic aberrations when shooting this brightly lit chrome.

I’ve not used a pre-1980’s zoom lens that didn’t produce some purple-fringing in a shot like this. Kudos to Minoltas engineers because there was none. Zoomed 400% in the 42 megapixel RAW file I could see nothing but bright chrome and colorful rust. 80mm @ F4

The Jelly Palm in our front yard is full of fruit this time of year. I shot this with the lens’ Macro mode enabled. 40mm @ F2.8

Just a bowl of bananas on the dinner table. Shot somewhere around 50mm @ F5.6

The Magnolia tree in the yard is sprouting new buds. Macro mode, 40mm @ F2.8. In the shade and backlit, color and contrast is good and the out-of-focus background is pleasantly smooth and non-distracting.

My second oldest daughter was kind enough to pause a moment for this final shot. 80mm @ F2.8

What can I say? The lens is awesome. All the effort put into designing this strange Gearbox-driven lens seems to have resulted in an excellent mid-range zoom lens. When I first started shooting with it, I did find it a little fiddly using a lever and wheel to make adjusts but after awhile I grew fond of it; it’s actually really fun to handle.

You don’t hold this lens like you would a traditional zoom, with your hands wrapped around the barrel. I keep it propped with the gearbox resting on the up-turned palm of my left hand and use my thumb to move the focal length lever and index finger to turn the focus wheel. The travel distance of both is just right so that you aren’t moving your fingers outside their natural range or having to make repetitious movements.

I can highly recommend this lens to anyone wanting to own a piece of history and/or turn some heads on their next photo walk. Comparing this to my favorite zoom lens, the incredible Minolta MD 35-70mm f/3.5, I would say it at least equals it. They’re both around the same size and weight and have a similar range of focal lengths. In fact, this Minolta 40-80mm f/2.8 lens is the antecedent to the 35-70mm f/3.5 (thus, for giggles, I used it to shoot the lens photos).

Minolta likely found that the unusual design and complexity of making this Gearbox lens was cost prohibitive and went back to the drawing board to come up with a balanced compromise. They only made two versions of it before canning the whole idea. The lens I have is the 1st Gen ‘MC’ version. An ‘MD’ version was made in 1977 and after that they called it quits.

Both versions can still be found for sale online, but I’ll warn you, this lens is priced for the committed collector.


Tom Leonard is an engineer, amateur photographer, and gear collector who travels around the world for work 30 days at a time. You can read more about Leonard’s travels and see his photography on his website.

This article was originally published on Tom’s blog, and is being republished on DPReview with express permission.

Articles: Digital Photography Review (dpreview.com)

 
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