High ISO Compared: Sony A7S vs. A7R vs. Canon EOS 5D III
1 Introduction | Shootout
Sony's A7-series lineup has garnered quite a lot of interest amongst camera enthusiasts, striking an appealing balance between image quality and size. Both the A7 and A7R bodies, as well as the native FE lenses Sony has recently introduced, are remarkably small and lightweight - especially when you consider the quality of images they're capable of producing.
The A7S is Sony's newest entry in its full-frame mirrorless lineup. But where the 'R' in A7R stood for resolution, the 'S' in the 12MP A7S stands for sensitivity. Furthermore, with its full-sensor readout and 4K video capabilities, the A7S is as much a camera for video as it is a camera for stills. And let's face it: there are very few videographers and photographers who wouldn't be thrilled by a camera offering higher sensitivity and impressive, low noise, high ISO performance.
Now, this purported increase in sensitivity comes at a cost: in the face of cameras with ever-increasing megapixels, the A7S comes in at a rather paltry 12MP. Lower resolution and higher sensitivity are certainly not unheard of - the Canon 1DX and Nikon D4S both top out at relatively modest resolutions of 18 MP and 16MP, respectively (though this is partly done in the name of speed). But is the resolution of a bygone era (Canon EOS 5D anyone?) a worthy tradeoff for the still image and video quality enhancements? Sony certainly seems to think so.
We just got our hands on an A7S, and have been busy putting it up against its competitors to see what advantages it offers and, quite frankly, to see if the claims regarding its low light performance are accurate. Particularly, some of us here have been curious as to whether not the increased ISO performance is significant enough to warrant the resolution tradeoff when the A7S is put up against its older sibling - the A7R.
Why make this resolution trade-off at all? Leaving aside video considerations (such as simplifying full sensor readout) for now, lower resolution sensors can increase pixel-level performance (because bigger pixels capture more light), but it's typically total light gathering area across the entire sensor that is a major determinant of ISO performance, all else being equal. So, to see whether the A7S offers anything beyond the pixel-level benefit its lower resolution would lead you to expect, the higher resolution image is normalized to the resolution of the lower resolution camera. Ultimately, for the A7S to make sense to stills as well as video shooters, Sony's engineers need to have exploited some of the other advantages that well-designed larger pixels can potentially bring *1.
We put the A7S up against the higher resolution A7R to see if the A7S offered any significant high ISO advantages over the A7R when the output of the A7R was downsized to that of the A7S. Furthermore, we pitted the A7S against a professional DSLR not too far outside the price range of the A7S. And so, we bring you this real-world comparison between the Sony A7S, Sony A7R, and Canon EOS 5D Mark III.
We shot a night scene that included a range of tones from deep shadows to bright highlights to get a comprehensive idea of noise performance of these cameras at various ISOs.
We waited until midnight to ensure minimal changes in ambient light during the course of our shoot (summer days are long in Seattle). In order to level the playing field for all three the cameras we did a few things:
- Used the same lens (Canon 24-70 f/4L IS) for all cameras. A Metabones Smart Adapter III was used to fit the Canon lens on to the Sony bodies.
- Aperture and shutter speed were matched across all cameras for any particular ISO setting.
- RAW files were converted in ACR 8.5 to give relatively consistent rendering across cameras. This was done by manually selecting white balance per camera, and adjusting Shadow Tint as necessary at higher ISOs in order to avoid magenta-tinted blacks. Sharpening and noise reduction were left to ACR defaults (Sharpening: 25 | Luminance NR: 0 | Color NR: 25).
Do note, however, that (1) nobody in their right mind would boost high ISO JPEGs in this manner (it's preferable to digitally boost Raws over JPEGs), and (2) when we did boost the high ISO Raw files in ACR, significant noise resulted. This itself speaks to the value of the higher ISO modes on the A7S (if you need them, that is), but also indicates that a more careful balancing act of noise reduction, sharpening, and exposure boosting would be more appropriate to obtain the 'simulated' higher ISO values than by simple (digital) exposure boosting.
Without further ado, let's get to the comparisons. Below and on the next page you'll find a variant of our typical studio scene widget. Have a play with it (further instructions after the widget), then view some of our specific thoughts on the comparison on the next page. By default we've set the widget below to compare the A7S vs A7R, but you can compare either camera to the Canon EOS 5D Mark III as well. And, as always, all files are available for download if you would like to tinker yourself.
Using the Widget
The widget above and on the next page is a variant of our typical studio scene widget. At the top is a drop down menu that allows you to select 'Normalized (12 MP)' or 'Native Resolution'. 'Native Resolution' indicates that images retain the maximum resolution the camera is capable of, whereas for the normalized analysis, images were downsized to 12 MP (using the bicubic resampling method).
As usual, we also have the Full, Print, and Web buttons at the top right of the widget. Full will maintain whatever you've selected in the top, center drop-down menu (12 MP for the normalized analysis, and full sensor resolution for the native resolution analysis). Print will downsize all images to 8 MP, while Web downsizes all images to 5 MP.
*1 For example, lowering cumulative sensor read noise, increasing effective sensor efficiency, and other factors that - to prevent this article sprawling - we won't elaborate upon further here.
|Body Only, Base|
|Canon EOS 5D Mark III 22.3 MP Full Frame CMOS Digital SLR...||See price on Amazon.com|
|Canon EOS 5D Mark III 22.3 MP Full Frame CMOS Digital SLR...||See price on Amazon.com|
|CZ54-1-2 by TrickTheLight|
from anything you can do I can do better
|Fork-tailed Sunbird On Ivory Coral Tree by cntlaw|
from A big year - birds 2019
|Washing day by Jill Hancock|
from -Minimum Wage- (non-human shot in Full Colours Only)
The Auschwitz Museum has asked visitors to be more respectful after an upsurge of pictures posted on social media showing people posing on the train tracks that lead to the main gate.
This week Chris and Jordan take the new Leica Q2 for a spin, and while most of us in the Northern Hemisphere are welcoming spring, they head even farther north than usual to visit ice castles. Because #Canada.
Harvard is facing a lawsuit over profiting from 19th century daguerreotypes that captured the portrait of a slave and his daughter on a South Carolina plantation.
From the detailed textures in rural landscapes to the incredible lighting inside futuristic buildings, the photorealism of Unreal Engine 4 is blurring the lines between fiction and reality...you know...aside from the spaceship.
According to a report from The Informant, a number of Instagram users' passwords were shared as plaintext in URLs used to download their data.
We've added Panasonic's new Lumix S1 and S1R full-frame mirrorless cameras to three of our buying guides. If you're looking for a quick summary of each model, then have a read.
YouTube channel Photoshop Cafe has shared a video detailing ten tips and tricks you can do to both fix and speed up Photoshop when it's running slow and sluggish.
It's not going to be the banger of the year, but it'll get a few laughs.
DJI has confirmed its drones won't be affected by the GPS 2019 week rollover.
Dogfish Head Craft Brewery has teamed up with Kodak to release a beer that's capable of doubling as a film developer.
The Diana Instant Square is a retro-inspired camera with manual controls that's fun to shoot in good light, but largely unpredictable in its operation.
Residents of a Paris street plagued by Instagrammers, selfie takers and music video crews are asking the city government for a weekend and evening ban to give them some peace.
The adapter plugs into the Osmo Pocket's USB Type-C port and features a 3.5mm TRS jack to plug in various external microphones.
Checkout allows Instagram users to select products for purchase and make payments directly in the app.
GauGAN as it's known, can create photorealistic images from basic drawings using the power of artificial intelligence.
The EOS RP is Canon's latest full-frame mirrorless camera, with diminutive dimensions and a diminutive price. Find out how it stacks up and get our thoughts in our early review.
Montana judge Dana L. Christensen has ruled the Republican National Committee did not infringe upon the copyright of photographer Erika Peterman after they took a photo from a Democratic candidate's Facebook page without permission and altered it to use in a derogatory promotional mailer.
Nikon has launched updates for three of its programs to address various bugs and glitches that could cause crashes and unwanted results.
LEE Filters has launched the LEE100, its next-generation filter holder that improves the design and looks in all the right places.
With the arrival of some much-needed sunshine and final production firmware for the Panasonic S1, we've been able to get outside and really start putting the camera through its paces.
Importing, culling and tagging photos is about to get a whole lot faster and look a whole lot better with the impending arrival of Photo Mechanic 6.
On its own, the FTZ adapter retails for $250 and when bundled it dropped the cost to just $150. Now, Nikon is offering it for free with all Z6, Z7 purchases in the United States.
Profoto said it spoke with Godox back at Photokina 2018 and continues to contact Godox in an effort to stop it from marketing its V1 light.
Product renders in Italian publication Notebook Italia show an unusual design that conceals all cameras with the help of a slider mechanism.
Canon says its new EF 400mm F2.8L IS III and EF 600mm F4L IS III lenses can suffer from an intermittent flickering when shooting video in M or Av modes with certain cameras.
Leica recently announced the Q2, a digital rangefinder with a fixed 28mm F1.7 lens. It's a heck of a lot of fun to shoot with, but is it right for you? Based on our time with the camera, and its specifications, we've examined how well-suited it is for common photography use-cases.
Now that our Panasonic Lumix S1R has final firmware, we couldn't wait to get out shooting with it - and we also tried the high-res mode, which combines files to get 187 megapixel images. Because sometimes, 47 megapixels just isn't enough.
In this article, travel and landscape photographer Mitch Green encourages us to spend more time in the the field.
the lens lacks any electronics whatsoever and is constructed entirely of glass and metal. Of course, that comes at the expense of weight — this thing weighs in at 1.1kg / 2.43lbs.
Drones can be useful tools in urban areas, where they're utilized for everything from news reporting to building inspections, but flying in these areas requires careful preparation. Here's what you need to know to do so safely.