Latest or all posts or last 15, 30, 90 or 180 days.
Welcome to diglloyd.com
In-depth review coverage is by subscription.
Also by Lloyd: MacPerformanceGuide.com and WindInMyFace.com
First-time visitor
Memory Deals, Thunderbolt Drives, Performance Upgrades, and More

Sony: Which Lens Corrections are Baked Into the Raw ARW File?

Get Sony mirrorless at B&H Photo.

I had posted Automatic Correction for Lateral Chromatic Aberration in Adobe Camera Raw yesterday, and William K writes in response:

Lens profile settings in ACR/Lightroom is a mess at the moment. My own testing with a Sony A7s and 16-35mm lens shows the following inconsistencies:

1. Distortion — This setting appears to be the only one with some consistency. The raw file is unaltered irrespective of the A7s lens correction setting. The distortion correction in ACR/Lightroom also looks ok when compared with a corrected a jpeg.

2. LACA (lateral chromatic aberration) — LACA correction is always applied and baked into the raw files irrespective of the A7s lens correction settings. The correction in the raw file is however not as effective as in a corrected jpeg which means that in some cases you still have to apply LACA correction to raw files in ACR/Lightroom. An uncorrected jpeg clearly shows the full extend of LACA in the lens but for some reason the raw file correction in the camera is somewhere between this and the corrected jpeg.

3. Vignetting is very problematic. If you use vignetting lens correction in the A7s that correction is baked into the raw file which will lead to over-correction when the lens profile is applied in ACR/Lightroom. The vignetting correction that is baked into the raw file is virtually identical to that of a corrected jpeg.

Lens profile settings use to be in the “set-and-forget” category. The normal practice was to enable this in the camera which will ensure corrected jpegs and videos without affecting raw files at all. With the latest trend you really have to jump through hoops to ensure consistency. To make it worse virtually none of this behaviour is well documented.

DIGLLOYD: this assessment held only one surprise for me: the camera baking LACA correction into the raw file. I’m not sure it’s true that it is less effective (see below) nor as yet have I definitively concluded that it is baked in.

Examination of my recent Sony A7R raw files with Iridient Developer (which allows all corrections to be disabled) suggests that indeed LACA correction is baked into the raw ARW file. While there can be lingering minor chromatic errors seen, they are mild and appear to be another type of chromatic error and/or some deviation in the particular lens from the LACA-correction modeling for the lens design. Of course, shooting a non-electronic lens via lens adapter will not result in correction, since the camera has no knowledge of which lens is in use.

Why would there be a setting in the camera for the correction, if it baked into raw files by the camera anyway? When I shoot Sony, I set the following, does the camera simply always disregard its Chro Aber Comp setting?

Shading Comp = Off
Chro. Aber. Comp = Off
Distortion Comp = off

In general, non-adaptive (non lens specific) correction for LACA is a problem. For example, with the Sigma DP1 Merrill, if my camera’s files are corrected by Sigma Photo Pro for LACA, the image actually develops color fringing one one side with the correction enabled where there was none without correction, even as the color fringing is removed on the other side of the frame.

Other cameras use automatic correction. For example, Leica M reads the 6-bit lens code and applies vignetting and color shading (color vignetting) correction, baking this into the raw file. It can be disabled, but the results are horrendous. Moreover, this correction is peculiar to the ray angle issue with Leica M rangefinder lenses on digital. From what I see, Fujifilm is also into correction; it’s just done as Fujifilm sees fit in some aspects. Few vendors even bother to document or clarify what is being done; the manuals are an abject failure in terms of explaining (“Foo setting = do Foo”, a circular explanation).

diglloyd Inc. | FTC Disclosure | PRIVACY POLICY | Trademarks | Terms of Use
Contact | About Lloyd Chambers | Consulting | Photo Tours
RSS Feeds | Twitter
Copyright © 2008-2017 diglloyd Inc, all rights reserved.