Every time I export a raw from RawTherapee, it looks horrible. It’s ultra grainy and makes a Canon 7D quality RAW look like a really bad iphone picture from a poorly lit room. What’s the problem?
Sample raw and resulting jpeg?
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It’s hard to say what’s wrong without a sample for us to see the problem, and a raw file to attempt to give you a possible solution.
You could use a service like http://filebin.net (or Dropboxreferral, or Google Drive, etc…)
Sure. See here
File IMG_8569.jpg (6.8MB original file) is a grainy example even when auto scaled in a browser.
and the parent RAW file (IMG_8569.CR2 at around 25MB) is also in that directory.
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The raw file doesn’t download for me; it ends up at 7 kilobytes.
The image is very grainy because it’s taken at ISO 2000.
To reduce the impact of color noise, you can change the demosaicing method to LMMSE like this.
(screenshot courtesy another post by @patdavid following up an earlier one of my recommendations for LMMSE)
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@777funk
The picture is taken at ISO 2000 and you didn’ apply “Noise Reduktion”.
Noise Reduction is not automaticaly applied in RT.
See; RawPedia - Noise Reduktion
btw: Can’t download the Raw file.
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Ahhh! I didn’t notice that. I had accidently set ISO to Auto. Whoops. I’ll have to try something at ISO 200 and see what happens. Seems like I’ve had some similar experiences at ISO200 as well. The camera JPG almost always looks better (as in less grainy) than what comes out of RT.
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Cameras always apply some amount of noise reduction even at base ISO in their JPEGs.
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@777funk http://rawpedia.rawtherapee.com/
Specifically:
Getting Started - RawPedia
Editor - RawPedia
Upload files using http://filebin.net/
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This is actually often a first step for many users, I think - trying to replicate the in-camera results. It may drive you nuts running down that rabbit-hole, but I’d be lying if I said I didn’t also start down the same path long ago.
These days, I’ve found that I prefer leaving some luma noise and spend most of my time trying to reduce chroma noise/blotches instead. The luma noise feels more like good ol’ fashioned film grain somewhat to me, so I don’t mind it as much. Sometimes I’ll spend a little time trying to reduce their prominence but it always comes down to a balancing act between reducing that noise vs. losing details.
That’s good to know! I guess that’s where it goes from art in photography (not implying my outdoor snapshot would fit the “art” category) to art in post processing. Looking forward to experimenting more.
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I’ve been using RT since last summer and I continue to learn more and more as I gain experience with it. For example, recently learning that, duh, if you have a high ISO image, consider first turning off sharpening as that might reduce noise without having to even turn on noise reduction.
I try to shoot at low ISOs when possible, but it’s winter now so there’s less ambient light and I have a 4 year old and two 3 month olds so you can’t ask them to stay still. Sometimes the only way to get a good enough shutter speed is to crank that ISO.
So I was curious, if I’m at 1:1 zoom - if I switch the demosaicing from amaze to LMMSE - will I see results in the preview window? Also, what do I give up in the tradeoff of going away from amaze?
At 1:1 or bigger, the changes are visible.
LMMSE trades off maze artifacts for color artifacts.
This is most noticeable with yellow leaves against blue skies. LMMSE works by assuming that the color can’t change rapidly, but when it actually does it fails, blurring out the color and thus displaying the raw luminance of the pixels underneath.
Amaze…well I don’t know how it works, but in such situations it fails slightly more gracefully.
…
On the left here is LMMSE, and on the right is amaze. You’ll see green/purple artifacts in amaze, and lots of dots in LMMSE.
Personally I usually use LMMSE because it gives cleaner shadows.
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OK, I’ll certainly experiment with it in the future when I have high ISO images.
I have a similar problem. I have adjusted some parameters such that the image is looking quite good on my monitor - even at 100% Zoom.
But when I export is as (16bit) tiff or as jpeg (98% quality) I get a really ugly, noisy image.
What am I doing wrong. The resulting image is much worse than the original raw image.
When I so similar operations with Darktable, no such problems arise on export.
Many thanks for some hints,
Helmut
Example?
Try taking a screenshot of the photo in the editor window side by side with the output photo in a photo viewer, both at 100%.
@HJarausch Did you open the tiff in rt to make the screenshot? If so, did you (by accident) apply sharpness again to the tiff?
No, I’ve opened it with Eog (eye of Gnome).
Thanks,
Helmut