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dark current noise

Started Jan 5, 2016 | Discussions thread
OP alexisgreat Veteran Member • Posts: 6,459
Re: dark current noise

CrisPhoto wrote:

alexisgreat wrote:

...

That is very interesting and thanks for the graph it's quite illuminating! Where do you find dark noise data online, Christof? I have a lot of trouble finding it anywhere. Also, if dark frame subtraction is so good at reducing dark noise is there any drawback to using it (besides the fact that it takes twice the time that is.) BTW how does setting shading compensation to off help? Thanks!

I did some test shots and evaluated the noise with RawDigger.

My conclusion is that darkframe subtraction works better than expected on my EM1 and more or less as expected with the EM5.

Shading compensation is a big problem in AP (if you use a mFT lens). The picture borders are brightened automatically and you get very odd frame patteren surrounding your photo. I think the algorithm Olympus is using works only for daylight shots and works very bad with low light.

You can test it easily, take a mFT lens, open the aperture and take a darkframe at ISO 12800. I bet you will be surprised ...

Here is an old thread discussing the issue:

http://www.dpreview.com/forums/post/52652493

As shading compensation is done on RAW data, it is very hard to restore a shot if you enable shading compensation by accident.

Thanks, it is good we can turn shading compensation off in these cameras!  It is a pity you dont have the EPL-5/6 then we could have compared the dark noise between the smaller bodies and the larger ones.  What is the highest ISO and longest exposure you would use with these cameras for AP?

 alexisgreat's gear list:alexisgreat's gear list
Olympus C-7070 Wide Zoom Fujifilm FinePix HS20 EXR Fujifilm FinePix HS50 EXR Olympus E-520 Olympus PEN E-PL6 +3 more
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