Old SLR lenses: full-frame, focal reducer, or APS-C?
1 Old SLR lenses: full-frame, focal reducer, or APS-
It's all about the lenses, right? Well, no, it's about making images... but lenses have something to do with that. I know fast autofocus can be useful, and rangefinder lenses have a following, but old lenses designed for manual-focus 135-format SLRs are particularly appealing. Why? Because a wide range of such lenses are optically good, mechanically impressive, readily available, and reasonably priced.
The key to using most of those lenses is having a very short mount-flange-to-sensor distance so you can fit a glassless adapter and still focus to infinity; DSLRs can't do it, but mirrorless cameras can. The really cool thing about the Sony A7/A7R is that either can cost-effectively put a high-quality full-frame 36x24mm sensor behind nearly any old SLR lens. Of course, you can sort-of do that on an APS-C mirrorless camera using a focal reducer such as the original Speed Booster (SB) or the cheaper Lens Turbo (LT). As I write this, a new 24MP APS-C NEX-7 body and LT can be had for about $1100, while a 24MP A7 body is around $1700. In fact, a 20MP APS-C A3000 body and LT can be had for about $500. Those price differences could buy some really nice old lenses....
For SLR lenses, is an A7 really a big step up from a NEX-7 with an optional LT? To find out, I've done a little informal evaluation of the same full-frame SLR lenses on:
- A7 full-frame 24MP
- NEX-7 APS-C 24MP with Lens Turbo (LT)
- NEX-7 APS-C 24MP
- A7 APS-C crop 10MP
- A100 APS-C 10MP
The ancient A100 DSLR is in there because it has a 10MP APS-C sensor, matching the sensel size and APS-C crop resolution of the A7. It doesn't have the high ISO performance nor video modes of newer CMOS sensors, but according to DxOMark, the A100's CCD is otherwise shockingly competitive with modern APS-C cameras like Canon's 70D. I'm not saying anyone should rush out to buy an A100, but it's a good test case here.
You might be wondering why I'm so interested in comparing APS-C crops. Well, it turns out that most lenses have image quality (IQ) drop significantly as you move off axis. A lens that makes beautiful image centers can have horrific image quality in the corners. Then again, some lenses produce image quality that is quite consistent across the whole frame. For some time, I've been wondering how often the "sweet spot advantage" of taking the the center APS-C crop might produce superior image quality (at the same total pixel count) as actually capturing the intended full frame. Testing just a few lenses will not give the definitive answer, but it is at least a start.
The specific lenses used for these quick, preliminary, tests were a 35mm f/2 Super-Multi-Coated Takumar, 50mm f/1.4 Super-Takumar, and 70-210mm f/3.5 Vivitar Series 1 zoom. These are well-known and well-respected lenses that easily can be bought at prices well below any new lenses of similar focal length and aperture. My total cost for these three lenses was under $200, and even a bad shopper should pay less than $400. Thanks to their M42 mounts, all three can focus to infinity on E and A mount bodies via adapters; most other old SLR mounts cannot be adapted to the A-mount A100. I tested with a glassless M42->A, glassless M42->E, and FD->E LT focal reducer behind a glassless M42->FD adapter. Here are the contenders:
|Left-to-right: A100 + 70-210mm, A7 + 50mm, and NEX-7 + Lens Turbo + 35mm|
It is worth noting that the test exposures were all made as ISO 100 camera JPEGs. The images were scaled down to 900 pixels wide for posting here. With the lenses wide open, exposure was near the brightest the cameras could handle, producing color and exposure differences that are more due to deliberate operator error than camera flaws. The stopped-down exposures look much more consistent across cameras.
On with the testing!
|Base, w/ 24-70mm|
|Base, w/ Battery Grip|
|w/ 28-70mm, Base|
|w/ 28-70mm, w/ Battery Grip|
|w/ 28-70mm, w/ 55mm f1.8|
|w/ 28-70mm, w/ 70-200mm|
|scrum break away by al booth|
from Sport competition
|Chinese Acrobat by lim yau tong|
|Parking Deck by Olaf R|
from Your City - Parking Garage
|Communication Tech by alberto_b|
|With & without by OBellini|
from Empty - Full
In this weeks' Throwback Thursday article, Simon raises a toast to the Sony Digital Mavica FD71 - a little camera which used really big memory cards.
It's been half a decade since Canon first debuted the original 6D and finally its successor is here. So what does five years of innovation look like?
The Canon EOS 6D Mark II brings more resolution, better autofocus and faster continuous shooting to Canon's entry-level full-frame camera. And we've had the opportunity to shoot with one.
The Canon 6D Mark II will ship to consumers in August, but we've been able to do some shooting with a pre-production unit well in advance.
Rumors have been swirling around for a while, and Canon has just unveiled the long-awaited successor to the popular and long-serving EOS 6D. Read all about it in our hands-on preview.
Canon's latest entry-level DSLR is here. The new Rebel SL2 (EOS 200D) is the belated successor to 2013's Rebel SL1, billed at the time as the smallest and lightest DSLR on the market.
Nearly five years after the announcement of the EOS 6D, Canon has finally replaced it with the EOS 6D Mark II. The Mark II features an all-new 26.2MP Dual Pixel AF full-frame sensor, 6.5 fps burst shooting, a fully articulating touchscreen, 1080/60p video and much more.
Canon has announced the EOS Rebel SL2 (also known as the EOS 200D), which replaces the aging SL1. This ultra-compact DSLR features a 24MP sensor, DIGIC 7 processor, Dual Pixel AF system and a 3" fully articulating touchscreen LCD.
When one of his friends got a filter stuck on his $1,700 Canon EF 24-70mm F2.8L, former MythBuster Adam Savage removed it using an unlikely, terrifying tool: a band saw.
The New Yorker asked Magnum's famed photographers, in town for the agency's 70th anniversary, to go out and capture 'the fleeting beauty of New York City's golden hour.' This is what they shot.
Roger Cicala is a difficult man to impress, but he's been waxing lyrical over at Lensrentals about Sony's new 12-24mm wide zoom.
Glassware is one of the most challenging subjects to photograph, especially against a white background. This tutorial shows you how to do it with hardly any gear.
Handevision is now shipping its all-metal Iberit 90mm F2.4 short telephoto lens for Leica M-mount 35mm and full-frame cameras.
Isocell comprises four sub-brands: Bright, Fast, Slim and Dual which are tailored to specific mobile device market demands.
The new store will be located at the Fotografiska center for contemporary photography in Stockhom, Sweden and carry the full range of Hasselblad products.
A recent vacation gave Richard a chance to think about the needs of travel photography – and how our reviews might recognize the perfect travel camera.
Need more evidence that 2017 is the year analog begins its comeback? Well, welcome another new film stock to the world.
The winners of the 10th annual iPhone Photography Awards have been announced, and they're striking.
If you were disappointed by reports that the Sony a9 struggles with adapted Canon glass, you might be able to take some comfort from Metabones' latest update.
Blackmagic Design has dropped the prices of its Video Assist external monitor/recorders for a limited time. Prices of the SD card-based recorders will be reduced in all markets, while supplies last.
Instagram has started testing a new feature called 'favorites' that enables users to share photos with only certain people. Only a small number of users have access to the feature at this time, though it may roll out to everyone in the future.
Lensbaby has announced the Velvet 85 F1.8 for interchangeable lens cameras. The lens is available in Canon, Nikon, Sony E, Sony A, Pentax K, Samsung NX, Fuji X and Micro 4/3 mounts.
It's the end of an era. Parent company Micron has announced that they are discontinuing the Lexar retail brand. This includes 'memory cards, USB flash drives, readers, and storage drives.'
Youthful trainspotter turned adult photographer, John Sanderson has traveled across the United States, documenting the country's railroads. But you won't find any trains in his pictures.
Sony's new CMOS sensor is backside-illuminated and offers an all-pixel global reset function which should drastically reduce rolling shutter effect when panning.
Shoulderpod has converted its offerings into a lego-like modular system by offering all individual parts of existing products separately, allowing users to build exactly the rig they need for a specific project or simply replace a damaged part.
Photographer Felix AAA has spent the past ten years touring the world with a variety of musicians, capturing behind the scenes shots and portraits. He talks about some of his favorite images on the FujiFilm Blog.
A roll of film discovered in an Argus C2 from an Oregon Goodwill turned out to contain some incredible images – and has been re-united with the original owner's family.
Nikon's 28mm F1.4E ED appears to roundly complete the company's updated lineup of fast, professional prime lenses. We've already seen some initial images from a Nikon ambassador, but we've worked through a gallery of our own, with a lens of our own over the past week. Take a look.
Google is holding a competition that could see your Pixel photos gracing millions of screens.