Author Topic: I need help to take the perfect picture of my Canon 7D Fixed Pattern Noise  (Read 4419 times)

Brawl

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I bought the Canon 7D after a long period of savings (years and years). I bought the Canon 7D becaus I belived in the RAW video potential. I study to be a film director and I wanted my workt to be in RAW (it's awesome).

Now I face this huge problem it's called "fixed pattern noise" it literally ruins the image and I want to fix it. I'm not a developer guy but I'm sure that if we cooperate togheter we can fix it in some way. I will never give up about this.

Maybe we can solve the problem in photoshop, maybe some developer will help us but in some way I need to start doing something. The time is passing and I do not see many developments on the horizon. So I wish to start taking the best picture of the fixed pattern noide that I can have. I wish to find a way to subtract the noise (like a compensation).

My tools are:

Canon 7D with ML and Bootflag
Computer notebook with Win7

Any advice will be greatly appreciated! bye! :)


PressureFM

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Set the camera to do a manual sensor cleaning and then wait two minutes. Turn the camera off and on and it should have calibrated black levels, remapped hot pixels and so forth.

Please post an example of the Fixed Pattern Noise you refer to.

Brawl

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Brawl

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I will try to take a picture with the cup on the lens, then edit it to see if the pattern noise is visible. see you soon for any update.


Marsu42

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Now I face this huge problem it's called "fixed pattern noise" it literally ruins the image and I want to fix it.

You've just discovered the main problem with the 7d :-\

Fyi: the fpn problem has been somewhat lessened by Canon on newer crop models starting with the 60d. The problem is that this noise type invalidates a good part of the potential dynamic range so you always have to expose correctly or ettr. In postprocessing, there's also much, much less potential for raising shadows than on the best Canon sensors (1dx & 6d).

Unless some dev discovers the holy grail, you either have to live with it, get a more current model (70d) or for video the 5d3 I'm afraid to say, though the latter also has some fpn.

dmilligan

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FPN varies based on your camera settings (esp. ISO) and temperature, and it can also change slowly over time. So you need to shoot a dark clip for every clip that you want to correct with all the same settings. Basically after each scene you shoot, shoot a dark clip, just put the lens cap on and record for just a second. Then you can tell mlvdump to use the dark clip to correct the "light" clip (your actual footage).

http://www.magiclantern.fm/forum/index.php?topic=9861.msg94866#msg94866