Sony 'striping': here's the fix
|Take a look at the PDAF stripes across the female model's face in this image (cropped from an original vertical shot). The bad news is that it looks terrible. The good news? There's a fix.|
It's known as 'PDAF striping' and it's not limited to a single camera, or even a single brand. It's likely due to light reflections off the metal masks of on-sensor phase-detect pixels. Masked pixels, as opposed to a split dual-pixel design that obviates the need for metal masks, is to the best of our knowledge a design choice: the approach enables high performance AF even during 10 to 20 fps bursts.1 The unfortunate side effect is the potential - albeit rare - for single pixel stripes in transitions from blown areas to darker ones. Depending on your set of lenses and the kind of photography you practice, you might never see this issue, but if you do it can be unpleasant and distracting. Particularly if you print large, or pixel peep.
The striping does seem to be limited to certain lenses: the Sony FE 85mm F1.8 is particularly prone to this issue
In our shooting with the a7 III, prominent examples of bright stripes tended to show up up in images that contained a significant amount of flare or backlit subjects. It seemed to mostly be an issue with shots taken with the FE 85 F1.8, when subjects were captured with the intent of deliberately inducing flare (we saw it in a couple 100-400mm F4.5-5.6 GM shots, but it wasn't offensive).
We investigated the issue further with the help of our very own knowledgable forum members, and are pleased to announce that as of today there is at least two fixes available.
See the results for yourself:
This particular fix is courtesy of Professor Hank Dietz, who is none other than the fellow who developed a fix for Sony compressed Raw artifacts. His tool is available here. For now, it only works on compressed Raw files, but it works with Raw files from any Sony camera exhibiting the issue. That's important, because this issue is not isolated to the a7 III by any means (though its predecessor the a7 II doesn't appear to have any issues). It occurs with the a7R II/III, a9, R100 V - i.e., most cameras with masked pixels for on-sensor phase-detect AF (and not just limited to Sony).
Higher resolution bodies are less problematic because a single pixel stripe is a smaller proportion of the image. The a7 III and a9 also have more phase-detection pixels than any other camera Sony has introduced, which makes the issue slightly more pronounced on these cameras.
Striping does appear to be isolated to certain lenses though: the Sony FE 85/1.8 is particularly prone to creating this issue, and we were easily able to induce striping even in modest backlit shots like the one above (zoom into 1:1 on the flare above the toddler's hat). However, we've had less luck recreating the striping with many other lenses like the 55/1.8, FE zooms, or the various 35mm primes we've tested. There doesn't appear to be much aperture dependence, based on Jim Kasson's analysis of our test shots.
You need not worry... just run problematic Raws through Prof. Hank Dietz's repair tool, and you'll get a Raw file largely devoid of any issues
What does all this ultimately mean? Well, if you shoot a lot of backlit subjects and love flare, don't worry: you don't have to steer clear of the a7 III or Sony mirrorless cameras. Instead, you may wish to steer clear of certain lenses like the 85mm F1.8 or 50mm F1.8. But even then, you need not worry too much: just run your problematic (compressed) Raws through Prof. Hank Dietz's repair tool, and you'll get a clean Raw file in return.
To take advantage of Professor Dietz' work, you simply drag-and-drop a compressed Sony Raw file into the web application, wait a few seconds, and download the resulting file (you'll want to add '.ARW' to the end for your Raw software to read it properly). And voila - almost every trace of the striping is removed. In extreme cases, you may see some remnants of striping, but out of the files we tested, this only happened once. Oh, and if you have any feedback, please PM Hank via his DPReview profile.
There's another fix independent of Hank's work. We've been in touch with one of the contributors - forum member pippo27 - for the open-source RawTherapee Raw converter, and he's integrated a fix in the Raw processing pipeline based on an understanding of the exact locations of the masked PDAF pixels.2 It's already available in development versions you can download here, and will be included in the next major release. There's even a Photoshop fix developed by DPR forum member Magnar W, if you're past the Raw development stage or have a problematic JPEG.
While we're still trying to nail down the root cause of these issues to help us predict when, where, and with what lens this will be an issue, rest assured that you needn't worry too much: the occurrence is rare, and when it appears, you'll likely have a (quick) workaround. We do hope though that Sony itself addresses the issue in-camera, especially as Prof. Dietz suggests it shouldn't even be too computationally burdensome.
1Both Sony and Canon executives have hinted to us the higher performance of the masked approach, and the computational burden of the dual-pixel approach, respectively.
2Thanks to extensive investigations led by Jim Kasson, Bill Claff and forum member Horshack.
A new week, a new special edition Leica.
Reuben Wu's ethereal landscapes are lit by drone-mounted light sources rather than the sun or the moon. We talked with him about his process, the equipment he uses and what inspires him.
Earlier today, the Federal Aviation Administration issued a notice stating that recreational drone users are limited to where they can operate.
Chris and Jordan take a look at Canon's latest, tiniest Rebel and get a serious sense of déjà vu as they take a look at its still and video capabilities.
Nature photographer Erez Marom shares his experience shooting the famous Ijen volcano in Indonesia – from the best time to begin the hike to the crater to the equipment needed to withstand the toxic environment.
While Canon and Nikon have lost double-digit percentages year-over-year for their respective imaging divisions, Sony has managed to come out in the green, albeit not by much.
Photo software developer On1 has introduced an update of its raw processing application that it claims is up to 50x faster than the previous version and which includes a host of new features.
Don't expect any new features or functionality. These updates are simply to improve the overall stability of eight Sony camera systems.
A rotating mechanism on the Asus ZenFone 6 does away with the need for a front-facing camera.
Canon's diminutive Rebel SL3 (also known as the EOS 250D and EOS Kiss X10) is currently the smallest DSLR on the market, but it comes with a proven sensor, an updated processor, and more. We've taken our review copy to New Orleans and back, and put it in front of our studio test scene – see how it stacks up.
Instagram has brought live the update to its Explore tab that brings more content and better organization to the forefront of the user interface.
No one ever said 1TB of storage in a form factor smaller than your thumbnail would come cheap.
Honor has already revealed some sample photos including EXIF-data from its upcoming 20 Pro flagship phone.
The latest in a line of celebrities caught using pictures without permission, singer Ariana Grande is being sued over images she posted on Instagram.
Now that we've wrapped up our final review of Sony's mid-range a6400, we're taking it into account as a whole; here's how we think it stacks up for some common photographic use cases.
Nikon has released firmware version 2.0 for its full-frame Z6 and Z7 mirrorless cameras, and its all about autofocus. The update adds Eye AF, improves performance in low light, and allows for full-time auto-exposure subject tracking at 12 fps.
Adobe has released an update to Adobe Lightroom CC, Adobe Lightroom Classic CC and Adobe Camera Raw that includes a new tool it calls 'Texture.'
DJI has strayed away from drones and gimbals to unveil what might be one of its worst-kept secrets, the Osmo Action.
The latest high-end smartphone from OnePlus comes with all-new camera modules for rear and front.
Profoto has released the A1X, an upgraded version of its A1 speedlight that features improved battery life, faster recycling times, an updated display and up to 20 channels.
The Osmo Action is DJI’s first entry into the action cam space. The 4K rugged action camera utilizes DJI’s built-in stabilization technology, offers dual screens, and like the Osmo Pocket, is simple to use. Take a closer look.
Researchers in China have created a camera that can record through the atmospheric pollutants of Shanghai to pick out objects just 60cm (2ft) high at a distance of 45 kilometers (28 miles).
Adobe has sent out an email informing Creative Cloud subscribers that using older versions of its Creative Cloud apps could put them in jeopardy of lawsuits from third parties.
New York Times Director of Photography Meaghan Looram announced to staff in a note that has been shared on Facebook that the publication's Lens photo blog will enter 'temporary hiatus' starting in late May.
Adobe is sending out emails to select Creative Cloud subscribers inviting them to register to test a beta version of its upcoming Photoshop for iPad application.
Kono! has launched a new 35mm film stock as well as a unique Sixpack that features half a dozen of its various color-shifting films.
Filmmaker Casey Cavanaugh has published a new video showing off his homemade 'GX-Pan' anamorphic lens adapter used with the $32k Hasselblad H6D-100C medium-format digital camera.
Rokinon's new 45mm F1.8 autofocus lens is the latest in its 'Tiny Series' lineup.