ISO 3.200 RAW files have exposure data crushed

IMoL

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Re: High ISO on small-sensor cameras: I have started using "frame averaging" for non-moving subjects; as the majority of noise is "random" - if you average several similar frames a large amount of the noise can be removed completely:

1. Take a number of identical photos at the desired ISO - I usually use 8 or 10, the technique works OK with 4+ - but a larger number is better.
2. Edit one of the pictures so that the exposure looks good in your RAW editor of choice (ignore the noise at this point i.e. turn OFF all noise reduction).
3. Apply the same settings to the other frames in the sequence.
4. Open all the frames as layers in Photoshop (in Lightroom you can do this automatically, in other RAW editors, you may need to do it manually in PS)
5. If you shot handheld, then it's best to do a Edit:Auto-align Layers from the PS menu at this point.
6. Select all the layers and combine them into a Smart Object.
7. In the PS Menu select Layer:Smart Objects:Stack Mode:Average
8. Enjoy your largely noise-free image

It sounds like quite a bit of work, but once you have done it a few times, it really only takes seconds for the PS part.

There are some limitations: This does not work well for images with moving objects - you will get ghosting (unless you are willing to spend some time manually masking different layers). Step 5 is very important if you shot handheld.

This will NOT work if you just take one image and duplicate it - the noise pattern will be the same in the duplicates - they need to be physically different captures.

Side benefits: You can also use this technique to remove moving people/vehicles from e.g. an architectural image - sometimes you will need to take more frames for this though.

This also works for handling high dynamic-range images at lower ISOs where you need to pull up the shadows a great deal - it removes a lot of that noise as well.
 
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RAH

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Not that damn cat again! :roflmao:
And if you're going to use a cat as a subject to shoot for instructional purposes, shouldn't it be BLACK?!? I mean, that's the hardest condition, right? (to make it look black, still have some details, etc.). A medium-grey cat seems almost like cheating. Hey wait - now I know what's happening here, this IS a black cat - @John King just doesn't know how to handle such a situation!! :D
 

John King

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And if you're going to use a cat as a subject to shoot for instructional purposes, shouldn't it be BLACK?!? I mean, that's the hardest condition, right? (to make it look black, still have some details, etc.). A medium-grey cat seems almost like cheating. Hey wait - now I know what's happening here, this IS a black cat - @John King just doesn't know how to handle such a situation!! :D
Blue cream tortoiseshell Burmese, to be exact ... ;) :rofl: .

Close to middle grey, I suppose ....
 
Joined
Jan 19, 2019
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France
Here's an example of ISO 6400 with profiled denoise in darktable:
20210806-2230-8060040.jpg
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I think it has enough detail and tonal range. Good enough for online viewing and for printing (if it were a better picture). My FF would have done slightly better but nobody would see the difference without pixel peeping.
 

Growltiger

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It is best to keep a black cat in a coal cellar to carry out these sort of tests:

Cat%20in%20coal%20cellar.jpg
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