PPI means nothing, ignore it.
Learn more about what it is here:
If you disable the Resize tool, you will get a full-sized, 100% image.
Local editing is not possible in RT, but RT can export the image directly to GIMP.
Thanks Morgan,
for the toolā¦ Iāve argued that there is any other way than external editor.
Speaking about resolution, please take a look at the 2 screenshot
As You may see the result is a 72ppi image. I need it to be 300.
I canāt find a way to do it in RT.
Thanks for your support.
In Photoshop, just change the 72 to 300.
Too basic to be usefulā¦
Easy, size and resolution.
That means no lost of time resizing elsewhere 
Hi @Gianni_Saccardo,
without knowing the output size in inches (or in some saner unit like cm :-), saying that you need ā300PPIā doesnāt mean anythingā¦ what is the output size you want?
Iām developing some images for a book on Blurb, they ask for a certain size and a certain resolution, having to resize all in some external editors sounds tricky and need a passage more, this means time.
After all RT is a great piece of software, sharpening and noise reduction modules are first class product.
Alsa color correction is quite easy and powerfull, local contrast and retinex works perfectly.
But not having the possibility to export in a certain size on a certain resolutionā¦ make no sense for me!
(A brush for local correction would be the perfect gift)
As you can see from the screenshot, I was expecting a 34x51 cm /300ppi image.
At the end I had a 72x200cm /72ppiā¦
Which means you need an (approx) 6000x4000 image. When printed at 300ppi resolution, it will result in 6000/300 x 4000/300 inches, i.e. 20x13.33 inches, i.e. 50.8x33.8 cmā¦
Or perhaps you are asking that the intended PPI is part of the image metadata?
If this is the case, this should do (assuming your image is actually 6000x4000):
$ exiftool -XResolution=20 -YResolution=13.3 -ResolutionUnit=in FILENAME.tif
So what youāre really asking for is not setting some metadata tag, but changing the pixel resolution of an image to fit a given physical size at a given pixel density. That is not easily doable yet. Keep an eye out on issue #54.
There must be something Iām missingā¦ 
sure it would be convenient to have this in RT, but if you know the PPI, determining the required size in pixels is not that hard, isnāt it?
@agriggio itās not easily doable in RT. Youād either need to whip out the calculator.exe, or abuse the crop toolās PPI calculation. Neither is user-friendly.
Ok, found how to do it.
CROP panelworks only exporting a jpg, tif comes out at 72, strangeā¦
It could workā¦ tif, would be better, but it works.
@Morgan_Hardwood Morgan, are you the engineer behind RT?
@Gianni_Saccardo JPEGs come out with XResolution=YResolution=300. TIFFs donāt have those tags set at all. The PPI setting in the Resize tool does not get saved as a tag.
@agriggio and I are from the RawTherapee project, there are others.
Iāll see what I can do about #54 once Iām done with a few other issues.
Thanks a lot for your help.
I think that RT worth gold, so developping it is a great (and hard job).
@agriggio I think you are italian, right?
Tell me how may I contribute (not only economically) to enhance this wonderful project.
I see a great potential in it!
Iām sure @agriggio has his own list of ways to help, but my list is:
- Use the software
- Report bugs and issues that you encounter and have the patients to work through the issues.
- Produce quality works with the software and share that work, telling others about your toolchain
- More actively promote the software, write tutorials, make demo videos, present to your local camera club
- Participate in develoemt by making feature requests
- Triage bugs, help new users find solutions to issues
- Write code
- Donate money
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