Can you export tiff and compare noise to darktable?
Then, can you export from that tiff to jpeg in another program, at 100% jpeg quality, and compare that to a jpeg export from dt at 100% quality?
Makes no difference; tiff is just the same as jpeg.
Try 95 or 100 but not 99…Strangely I feel I recall some other issue in the past with JPG artifact if someone tried 99%?? I just can’t recall the exact issue…
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No difference I can see.
I exported your edit and then in DT I scrolled to 100% and took a snapshot of the raw and then I advance to the jpg and compare …I really don’t see a lot of difference and what I do see is actually very marginally but less noise in the jpg…at least zoomed in and looking at the face of the bald gentleman??? I uploaded by exported jpg from your edit…
I can’t quite grasp your explanation of what you did, but here is a shot of the shirt on the right exported at 100%:
This is from dt:
So I use LittleCMS enabled and I dont use prefer performance to quality…not sure if this impacts in any great way what the preview in DT looks like… Basically i downloaded your canon file and xmp and did a strait export…so this is noise Reduction on…Then I rolled the scroll wheel in place to zoom in to 100% , took a snapshot…then advanced to your jpg export or at least the one done on my pc…it is automatically at the same zoom and location …so now the raw is to the left and the jpg is to the right…sliding the snapshot line across I can see very little difference…how are you viewing your jpg??
My settings are the same as yours.
Advance to the export? Within dt?
With the xmp you posted I don’t get a difference but your screen shot of what you see in the raw file preview does appear to be different?? Video o f raw snapshot vs exported jpg…
I use IrfanView to view jpegs. I have compared it to other viewers I have and see no difference.
I don’t load jpegs when I open a folder, but I did that for this folder just now and opened the jpeg in darkroom. Then I opened the edit in darkroom of another copy of dt. This is the jpeg, in darkroom:
xmp in dt copy, darkroom:
Just a note, demosaicers can handle sensor noise better or worse. DT master has lmmse available now, it’s certainly better than the other algorithms for high ISO images. Worth a try …
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I figured out how you did that and compared the xmp to the jpg with no zoom and at 100% zoom. I can’t see a difference at 100%, but I clearly do at 0%. I am baffled.
Thanks for the tip. I’ll give it a try, but my current problem is with exported jpgs not viewing the same as the preview I see when editing.
What are your settings for previews …are you using the performance setting…others may also have insight why you would see a difference?? I’ll go back and look at 0 although most things like noise and sharpness are always evaluated at 100% otherwise you are likely combining pixels and so it would look less noisy
There is one in general as well…performance vs quality…but I think its just that at 100 percent you show a true representation of all the pixels…when you fit to display you don’t if you have a 1920 display but an image that is 5 or 6 or more K wide then you are shrinking it to fit and this will alter the preview…thus sharpening and detail related issues are dealt with at 100%
Set for that.
I’d like to know if RT does this. I haven’t used it but for a little while a couple years ago, so a quick test is not forthcoming from me.
EDIT: see 89 below.
except of course jpeg is lossy and assuming in this case the intention would be to use tiff as a lossless export format
I will see if you observe the same I suspect yes as RT doesn’t even correctly show noise or sharpening below 100%…ART has a setting to “simulate” or show the impact below 100%… bottom line for now clear that you have to evaluate at 100%
Wouldn’t export this. tif looks like jpg. I’d want to do an edit from scratch with, in particular, a similar crop. Wouldn’t even put it in BW, unless that is easy to figure out. The same problem exists in dt in color. I just want to see what an export would look like. I’m looking for a ballpark answer to the question of is dt causing this, or is it something to do with this photo.