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Tell your friends about us!Red Circles in underexposed pictures
- Thread starter ChrisH
- Start date
kosmoskatten
New Member
Hello all,
this is a firmware issue due to software vignetting correction as it seems. It becomes visible as you push a file too far.
Ricoh are not alone in doing this and the issue is apparent with other cameras such as the RX-1:
http://www.fredmiranda.com/forum/topic/ ... astmessage
Scroll down the page for a similar result with the Sony RX1.
I have not come across the problem yet on my GR but so far I have gotten the exposures within the extremes so I have not needed to lift shadows that much yet. I am not sure if there is a setting in the GR to turn it off. Must check, normally I switch everything off.
/ Henrik
this is a firmware issue due to software vignetting correction as it seems. It becomes visible as you push a file too far.
Ricoh are not alone in doing this and the issue is apparent with other cameras such as the RX-1:
http://www.fredmiranda.com/forum/topic/ ... astmessage
Scroll down the page for a similar result with the Sony RX1.
I have not come across the problem yet on my GR but so far I have gotten the exposures within the extremes so I have not needed to lift shadows that much yet. I am not sure if there is a setting in the GR to turn it off. Must check, normally I switch everything off.
/ Henrik
kosmoskatten
New Member
PS
Judging by the looks of the RX1 example with the hard transitions it does not seem like a natural optical vignetting but rather a software compensation that rears its ugly head. I strongly believe it is a software issue with both the RX1 and the GR.
Judging by the looks of the RX1 example with the hard transitions it does not seem like a natural optical vignetting but rather a software compensation that rears its ugly head. I strongly believe it is a software issue with both the RX1 and the GR.
odklizec
PK
Well, I thought about the possibility that the GR circles are caused by the vignetting correction. The problem is that the GR circles are too uniform with very sharp edges and the number of circles is too low to be useful for vignetting correction. Typically, the vignetting correction is done with smooth gradients. In other words, the effect seen in RX-1 photos is something I would expect to see in case of enabled vignetting correction. The GR issue looks somewhat different.
Frankoz
New Member
Hello All,
I have also experienced the ring problem in LR 4.1 on a couple of occasions now. I've had the GR a couple of weeks and put their appearance down to my screw-ups, however, as with others, it has shown up sporadically when correcting for under exposure in a backlit subject. Still a great unit, but this is a little disappointing.
Here's hoping that there is a simple solution....
rgds
Frankoz
I have also experienced the ring problem in LR 4.1 on a couple of occasions now. I've had the GR a couple of weeks and put their appearance down to my screw-ups, however, as with others, it has shown up sporadically when correcting for under exposure in a backlit subject. Still a great unit, but this is a little disappointing.
Here's hoping that there is a simple solution....
rgds
Frankoz
odklizec
PK
Hi reeluff,
I somehow overlooked your post with "dark-frame" test. It indeed appears to be a firmware issue, or better said, the side-effect of automatic vignetting correction or something like this. An option to turn this feature OFF would be greatly welcome. Let's hope this request will not hit the deaf ears as it was in case of true NR OFF
I somehow overlooked your post with "dark-frame" test. It indeed appears to be a firmware issue, or better said, the side-effect of automatic vignetting correction or something like this. An option to turn this feature OFF would be greatly welcome. Let's hope this request will not hit the deaf ears as it was in case of true NR OFF
odklizec
PK
Just to let you know folks, I've discussed this problem with my contact in Ricoh and I was told that Ricoh engineers are aware of this issue and trying to do something about this. No details were provided. But as with previous GRD models, we can expect a FW update with some fixes and enhancements. So hopefully, the first one will fix also this issue? I personally would like to see a switch to turn the vignetting correction OFF.
Here's an example. I've taken thousands of pictures and been very pleased, but I did have rings in two photos.
It was a bright summer day and I took a few snapshots of a building site, very informally as I walked by. The building was in shade, with strong back or side light. I don't remember giving it much thought, so I was likely in Aperture priority. I took about 5 frames and I think I realized at one point that the lighting condition were very difficult, so I tried exposing for the highlights for one frame.
Two of the pictures were very dark, almost black, with just a corner with sky exposed sort of properly. It was a bit strange to get results like that, but I didn't question it too much because the lighting conditions were quite extreme and I wasn't exactly being careful. However, when I raised the exposure in LR (quite a lot, like plus 4) I saw rings in these two dark photos.
I include one here and also one taken immediately after where the results were much more normal and the rings did not appear. I upped the shadows a little bit, otherwise its SOOC.
It was a bright summer day and I took a few snapshots of a building site, very informally as I walked by. The building was in shade, with strong back or side light. I don't remember giving it much thought, so I was likely in Aperture priority. I took about 5 frames and I think I realized at one point that the lighting condition were very difficult, so I tried exposing for the highlights for one frame.
Two of the pictures were very dark, almost black, with just a corner with sky exposed sort of properly. It was a bit strange to get results like that, but I didn't question it too much because the lighting conditions were quite extreme and I wasn't exactly being careful. However, when I raised the exposure in LR (quite a lot, like plus 4) I saw rings in these two dark photos.
I include one here and also one taken immediately after where the results were much more normal and the rings did not appear. I upped the shadows a little bit, otherwise its SOOC.
Attachments
autochrome
Member
Here is exactly the reason that makes this blog is valuable: a question is asked, and generally this kind of question remains unanswered, unfortunately...
Here, we quickly answered serious, credible, documented, without unnecessary words.I appreciate this very much! Thank's to all participators.
Here, we quickly answered serious, credible, documented, without unnecessary words.I appreciate this very much! Thank's to all participators.
odklizec
PK
Yes, the noise reduction improvement is only JPEG related.
Let's hope they will do something about the "concentric circles" issue. On the other hand, I was not able to reproduce/see this issue in the real world photos. But I guess it may be easily reproducible in case of stacked photos for HDR photography? So yes, I think it would be nice if Ricoh engineers would sort it out. If it's really caused be a "vignetting correction" feature, it would be great to have a simple switch to turn it OFF.
Let's hope they will do something about the "concentric circles" issue. On the other hand, I was not able to reproduce/see this issue in the real world photos. But I guess it may be easily reproducible in case of stacked photos for HDR photography? So yes, I think it would be nice if Ricoh engineers would sort it out. If it's really caused be a "vignetting correction" feature, it would be great to have a simple switch to turn it OFF.
odklizec
PK
Tony, in my opinion, if you are not a HDR shooter, there is nothing to worry about this problem. It's not visible (or very rarely seen) in normal shots. I was only able to reproduce it by covering the lens, taking black shot and then extremely raising the exposure value in RAW editor. It's not something you would normally do?
It feels like it's not really a deal-breaker, and as you said, it's mostly on the extremes it shows up and I'm not an HDR shooter either, though sometimes in the PP I'd like to mess around with plugs and filters and really push things.odklizec":38e5ym1g said:Tony, in my opinion, if you are not a HDR shooter, there is nothing to worry about this problem. It's not visible (or very rarely seen) in normal shots. I was only able to reproduce it by covering the lens, taking black shot and then extremely raising the exposure value in RAW editor. It's not something you would normally do?
I read that someone said the Ricoh engineers are working on this issue, so that's a good thing, too bad it didn't end up on the latest firmware update though.
Let's hope for the next FW update.