Problems with Canon 5D mk2

questions about practical use of Neat Video, examples of use
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Six Ways
Posts: 1
Joined: Fri Apr 20, 2012 12:36 pm

Problems with Canon 5D mk2

Post by Six Ways » Fri Apr 20, 2012 2:06 pm

Hi, I've been using NV for a while with my Canon 550D with excellent results. I've built a series of noise profiles for the camera using the Neat Image calibration target. These profiles have qualities of around 85%, which I'm happy with.

I've recently been using a friend's 5D mk2 on a shoot, working under the assumption that I could do exactly the same thing - build some profiles and easily apply NV. However I've found it impossible to build good profiles using the calibration target.

NV tells me that most of the squares are not uniform or have clipping. I've tried all the settings I can think of, with different amounts of defocusing, different exposures, different picture profiles, shooting a printout and a high-quality LCD monitor, trying to get even lighting etc etc... nothing seems to work. I never even tried hard with the 550D, I just shot the printed target without any planning, and it worked great.

I've even tried just shooting a plain, evenly lit white wall, blurred out, and NV claimed it couldn't find any consistent area large enough to build a profile. I'm at a loss here! Any thoughts?

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Joined: Thu Sep 01, 2005 4:12 pm

Post by NVTeam » Fri Apr 20, 2012 8:18 pm

There may be not enough noise in some of the channels and then primary source of imperfections are the compression artifacts. They are usually non-uniform, which is reported by the profiler. However, they are very weak and using them for analysis will not really break anything in this case. So, the solution is to simply ignore those warnings and build a profile using such an area. After all, that is just an information message, a suggestion that may help to improve the results, in cases when it is possible to implement it. It can be ignored too. This is exactly the case when it can be ignored. And in this case please evaluate the results visually, using the preview, rather than just checking the profile quality indicator.

Hope this helps,

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