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 Peculiar vignetting problem with SONY A7RII and native Zeiss 
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Joined: Fri Oct 07, 2016 9:22 am
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Post Peculiar vignetting problem with SONY A7RII and native Zeiss
I have a problem with the time lapses I've shot with my Sony + Zess Loxia or Batis (basically native SONY lenses) Sony with native lenses applies some kind of vignetting, that really messes up the photos shot in sequence. Which spells real trouble for time-lapse people and this combo. I see this in all my time-lapses.

Here are two identical test shots I did today. The first one is 1 second exposure, the second one is 1.3 seconds. All other settings are the same. Shooting RAW, MANUAL, with disabled settings like NR, Profiles, etc. It's especially evident when playing back a time-lapse or just toggling between the two images. I'm sure some kind of software raw "correction" is being applied here by SONY. None of this happens with my Leica R lens on the sony body.

The question is what to do about this? I'm thinking about maybe shooting a white wall (like a big piece of evenly lit white paper) and then applying some kind of subtraction in Photoshop. Even if I manage to make it work, its still yet another extra step in the workflow, which slows the whole workflow down. Does this happen with other cameras / lenses, is this only a SONY thing?

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Fri Oct 07, 2016 9:25 am
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Joined: Sat Apr 25, 2015 7:34 pm
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Post Re: Peculiar vignetting problem with SONY A7RII and native Z
are you using a full frame lens?


Fri Oct 07, 2016 4:20 pm
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Joined: Fri Oct 07, 2016 9:22 am
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Post Re: Peculiar vignetting problem with SONY A7RII and native Z
Loxia and Batis lenses are both full-frame.


Fri Oct 07, 2016 4:27 pm
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Joined: Wed Jan 20, 2010 4:50 pm
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Post Re: Peculiar vignetting problem with SONY A7RII and native Z
I don't really understand the problem. All wide angle lenses vignette to some extent. Some camera manufacturers choose to compensate for this in the internal processing. If not it can be compensated later if deemed a problem. In fact for many images it can look better to leave it alone...


Sat Oct 08, 2016 4:44 am
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Joined: Fri Oct 07, 2016 9:22 am
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Post Re: Peculiar vignetting problem with SONY A7RII and native Z
The problem is: You take one photo at 1 second exposure, then the next at 1.3 second exposure and the photos are very different from each other. On the second 1.3 second exposure there is an unnatural jump in slightly blue color vignetting, to the point that when you do time-lapses, you don't have a smooth transition between the frames. It looks like its taken with another much cheaper lens.

This is not just a regular flicker resulting from time difference. This is happening on the firmware level where the firmware is applying some kind of abnormal "correction" to the frame, resulting in unnaturally strong vignetting between one frame an the next. Its mostly happening on all of my time lapses where exposure changes from 1 second to 1.3. This means I have to manually correct these frames, paint on the sides in LR to compensate the difference in light values, and adjust all of my time-lapse frames. This issue is happening with Loxia and Batis lenses. In real-world its a problem because it adds additional work to my workflow.


Sat Oct 08, 2016 4:54 am
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Joined: Wed Jan 20, 2010 4:50 pm
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Post Re: Peculiar vignetting problem with SONY A7RII and native Z
If the camera is changing aperture between frames then the amount of vignetting will change - maybe it's some thing to do with that? You might need to use the camera in aperture priority mode so only the shutter speed changes - not the aperture... also check if there is an option to disable camera from compensating for vignette.


Sat Oct 08, 2016 3:41 pm
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Joined: Fri Oct 07, 2016 9:22 am
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Post Re: Peculiar vignetting problem with SONY A7RII and native Z
Aperture is actually fixed as I've stated above. The only thing that is changing is the shutter speed. All other camera settings remain the same as I always shoot in Manual mode. This is not a user error. The more I test this on my end, the more I see the problem repeating itself every time. I also think other Sony a7 users who are planning on using their camera for time lapse should be aware of the issues this camera has with Zeiss Loxia and Batis lenses. This issue is mostly happening when the shutter speed changes from 1 second to 1.3 seconds. I'm now spending a lot of extra time in Lightroom, adjusting my photo sequences.


Sat Oct 08, 2016 3:59 pm
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Joined: Wed Jan 20, 2010 4:50 pm
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Post Re: Peculiar vignetting problem with SONY A7RII and native Z
Did you try disabling lens shading compensation? Look for "Lens Comp: Shading Comp"


Sat Oct 08, 2016 8:08 pm
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Joined: Fri Oct 07, 2016 9:22 am
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Post Re: Peculiar vignetting problem with SONY A7RII and native Z
That was a good advise and it partially helped! Thanks! The problem persists to a lesser degree. At least it's not as severe, but its still there. There is still a slight blue cast vignette between 1 and 1.3 seconds exposure. Shooting stills is not an issue here, but for time lapses I think it will still need to be corrected manually but I think it will be easier. It' still not acceptable to me personally to pay thousands of dollars in gear equipment to have to deal with post issues due to the hardware not working properly.


Sun Oct 09, 2016 8:14 am
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Joined: Fri Oct 07, 2016 9:22 am
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Post Re: Peculiar vignetting problem with SONY A7RII and native Z
Just saw how it continues on to 1.6 seconds exposures as well...


Sun Oct 09, 2016 8:58 am
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Joined: Wed Jan 20, 2010 4:50 pm
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Post Re: Peculiar vignetting problem with SONY A7RII and native Z
Mysterious if it only happens with certain lenses. That would indicate it's not shutter related. Have you also tried locking aperture wide open? Auto iris lenses can be inconsistent.

Finally - have tried the deflicker tool in the recent post...? "New Time-lapse De-Flicker Tool: TLDF (Mac App Store)" He seems to just shoot auto and the software takes care of everything...


Sun Oct 09, 2016 2:36 pm
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Joined: Fri Oct 07, 2016 9:22 am
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Post Re: Peculiar vignetting problem with SONY A7RII and native Z
Since all cameras apply certain corrections to RAW files prior to the files being written out, I think there is some kind of a mess-up on SONY / ZEISS side here. I mean I have a fully manual lens (Loxia 21) that has this issue. I do use LRTimelapse to smooth out all transitions between EV stops, but this issue can't be handled by that app. Will take a look at your suggested app and will continue asking Zeiss and Sony to give proper explanations on this issue. Thank you for your replies.


Sun Oct 09, 2016 2:48 pm
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Joined: Wed Jan 20, 2010 4:50 pm
Posts: 561
Post Re: Peculiar vignetting problem with SONY A7RII and native Z
It's hard to imagine how a lens could do this particularly if you can lock the aperture. Sounds more like processing or shutter. BTW - I thought the idea of RAW files is that they have no processing - they are "raw" . What the camera does do is attach messages which inform how to process it - ie. things like colour balance, tone. That's why you can totally change the white balance, just as though you had done it in camera. I would think the same might apply to the shading comp?


Sun Oct 09, 2016 3:25 pm
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Joined: Fri Oct 07, 2016 9:22 am
Posts: 8
Post Re: Peculiar vignetting problem with SONY A7RII and native Z
These days lens manufacturers rely on corrections done in camera prior to writing the RAW file. There is quite a lot of "baking" happening before you even get to play with the RAW files in Lightroom or whatever post workflow app you are using. Because it's only working with lenses that communicate with A7 and not with Leica R lenses, I know its not a shutter issue. Will investigate, for now time to retouch another timelapse.


Sun Oct 09, 2016 4:50 pm
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