Ben J. Posted September 13, 2017 Share Posted September 13, 2017 So I have been using my sony a7sii for a good few months, but always wasn't sure what the noise was suppose to look like for a regular functioning factory sony a7sii. It looked fine to me and never bothered me till now. I'm lately seeing a wall of thin noise in my shots. I don't know if this is how its suppose to look or if this grain is not normal. Please tell me. This was either shot at 1000 or 1250 iso, and this is set to exposure at 0 by what the camera is telling me to expose at. (no auto at all). Here is one with my picture profile with all color depth set at 0 and its not cine 4, or the slogs C0089.MP4 Quote Link to comment Share on other sites More sharing options...
Shirozina Posted September 13, 2017 Share Posted September 13, 2017 I can't see any noise on my UHD screen laptop (but my eyes can't focus close enough to be sure). Loading it into my NLE shows you are underexposed though with the whites peaking at only 80% so upping the exposure will help reduce any noise. Hope this helps? Quote Link to comment Share on other sites More sharing options...
Ben J. Posted September 13, 2017 Author Share Posted September 13, 2017 1 hour ago, Shirozina said: I can't see any noise on my UHD screen laptop (but my eyes can't focus close enough to be sure). Loading it into my NLE shows you are underexposed though with the whites peaking at only 80% so upping the exposure will help reduce any noise. Hope this helps? Thats the strange part, it shows on my camera that I'm over exposing if I go higher, I'm not sure why. Unless 0.3+ or 0.7+ doesnt mean clipping? I thought it did though. Even when I expose more, it still has the same amount of noise, but I'll do another test again when I get back home. Also, make sure you're looking for the noise in a dark room so you can see the shadows better. I notice it a lot on the corner wall and the desk. Quote Link to comment Share on other sites More sharing options...
Shirozina Posted September 13, 2017 Share Posted September 13, 2017 I don't use the exposure guide at all. I set the zebras to 105%, set the profile to cine 2 and place white just under clipping although this depends on the scene contrast as ETTR is not ideal for low contrast scenes. Quote Link to comment Share on other sites More sharing options...
Don Kotlos Posted September 13, 2017 Share Posted September 13, 2017 Are you using a Cine profile? Some of the Cine profiles use the full 0-255 range, while the display (& zebras) work on the safe zone of 16-235. So you might think you are clipping but only because in camera you visualize a smaller range. Quote Link to comment Share on other sites More sharing options...
Shirozina Posted September 13, 2017 Share Posted September 13, 2017 3 minutes ago, Don Kotlos said: Are you using a Cine profile? Some of the Cine profiles use the full 0-255 range, while the display (& zebras) work on the safe zone of 16-235. So you might think you are clipping but only because in camera you visualize a smaller range. Only Cine 2 / zebras 105% show the absolute clip limit on these cameras - all other's show clip before that actual limit. Also all cameras show clipping only on the green channel so you have to make sure you get a perfect WB otherwise you can clip on the red and blue channels and not be aware from the zebras. Quote Link to comment Share on other sites More sharing options...
Ben J. Posted September 13, 2017 Author Share Posted September 13, 2017 1 hour ago, Don Kotlos said: Are you using a Cine profile? Some of the Cine profiles use the full 0-255 range, while the display (& zebras) work on the safe zone of 16-235. So you might think you are clipping but only because in camera you visualize a smaller range. No, its not a cine profile or log profile. So are you saying I should use the judgement of my eyes and the histogram to set exposure? Shirozina said he couldnt see the noise, can you see it? Cause I can see it. 1 hour ago, Shirozina said: Only Cine 2 / zebras 105% show the absolute clip limit on these cameras - all other's show clip before that actual limit. Also all cameras show clipping only on the green channel so you have to make sure you get a perfect WB otherwise you can clip on the red and blue channels and not be aware from the zebras. Yeah I set a custom white balance for perfect wb, so that shouldn't be the issue. Quote Link to comment Share on other sites More sharing options...
Administrators Andrew Reid Posted September 13, 2017 Administrators Share Posted September 13, 2017 Looks clean as a whistle to me for ISO 1250. On many other cameras that shot would be fizzing like hell! Quote Link to comment Share on other sites More sharing options...
EthanAlexander Posted September 13, 2017 Share Posted September 13, 2017 3 hours ago, Ben J. said: Thats the strange part, it shows on my camera that I'm over exposing if I go higher, I'm not sure why. Unless 0.3+ or 0.7+ doesnt mean clipping? I thought it did though. That exposure is simply trying to judge the scene and place what it considers middle grey at 18%. It actually has nothing to do with clipping. Go ahead and use the histogram and zebras to get a better exposure judgement. 3 hours ago, Ben J. said: Even when I expose more, it still has the same amount of noise If you're exposing by adding more gain (raising the ISO) then yes, but if you add more light (either through aperture, shutter, or actual lights) then you can reduce the appearance of noise. Many people have found that using a cinegamma or s Log and over exposing is the best way to get a clean image. This is because you're lifting the image out of the shadows and the extended dynamic range of the cinegamma/SLog give you head room in the highlights. But again, do this by adding light, not gain. Quote Link to comment Share on other sites More sharing options...
Shirozina Posted September 14, 2017 Share Posted September 14, 2017 6 hours ago, Ben J. said: No, its not a cine profile or log profile. So are you saying I should use the judgement of my eyes and the histogram to set exposure? Shirozina said he couldnt see the noise, can you see it? Cause I can see it. Yeah I set a custom white balance for perfect wb, so that shouldn't be the issue. Yes use the Histogram and / or Zebras to set exposure. Your WB is not set correctly as the image has a blue/magenta bias - how are you setting WB? Quote Link to comment Share on other sites More sharing options...
Shirozina Posted September 14, 2017 Share Posted September 14, 2017 Here is the RGB parade in Davinci Resolve after the file is imported properly for Sony internal codecs (clip attributes set to full) - you can see how far the whites in the image are away from their clipping point and how the different channels are uneven which indicates an incorrectly set WB. I played the clip on my 27" workstation monitor and can see the very slightest amount of grain - pretty amazing for an underexposed shot at this ISO! Quote Link to comment Share on other sites More sharing options...
Ben J. Posted September 14, 2017 Author Share Posted September 14, 2017 12 hours ago, Shirozina said: Yes use the Histogram and / or Zebras to set exposure. Your WB is not set correctly as the image has a blue/magenta bias - how are you setting WB? Yes you are right, I think I changed the matrix filter (tint) on it in camera to get rid of some yellow (which would explain the blue spike) Quote Link to comment Share on other sites More sharing options...
Shirozina Posted September 14, 2017 Share Posted September 14, 2017 If it's any help I found that out of all the non Cine / S-LOG profiles that work well with video is 'portrait' with all the settings at minimum. It gives very reasonable DR and 'workable' colour. I'd also highly recommend Andrew's EOSHD Pro colour for these cameras. Sony cameras are capable of very good colour but they just don't seem to know how to create any profiles that make use of it........ Quote Link to comment Share on other sites More sharing options...
Ben J. Posted September 14, 2017 Author Share Posted September 14, 2017 18 hours ago, Andrew Reid said: Looks clean as a whistle to me for ISO 1250. On many other cameras that shot would be fizzing like hell! For some reason it won't let me upload other files giving me a 200 error? Quote Link to comment Share on other sites More sharing options...
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