Understanding ART - comprehension questions

Hello, trying to understand ART 1.10.1 (official version, not an alpha build). I have some questions and would like to ask if you can verify or falsify me? Please note, what I write below is no criticism or feature request, just me trying to understand what’s there. Just comprehension questions. I’m a “consumer” with current Windows 10 and with no coding-ability, no Linux ability. Thanks!

  1. Editing a JPG file : after a re-start, all edits are lost, including history list and snapshots. To keep edits, I need to “Save”. Right?

  2. Editing a RAW file : after a re-start, edits are still there, snapshots are there, but “History” panel is empty. Right? Are there other differences in the treatment of RAWs and JPGs?

  3. UI only in English, info only in English and French. No German UI avaible, right?

  4. Resetting a file to original : Is there one button to reset ALL changes from all panels and tools? (Aware of 1st state “Photo loaded” in History panel, that’s “Reset” in a way.)

  5. Collections : I take it there are no “collections”/“virtual folders” where you collect pics from different folders without physically duplicating them, say for presentation or printing. Right?

  6. Virtual copies : I believe there are no virtual copies? (Darktable can store several XMP files per pic and thus allow several versions of a file that hasn’t physically been duplicated.) Am aware of multiple snapshots, but they don’t show the variations side by side and the variations can get confused.

  7. In the File Browser in Inspect Mode, I can compare two pics even in 100%. That’s good to compare sharpness. But I can’t pan/scroll the pics independantly of each other, right? They always move together. (Am aware of Focus Mask and Loupe overlay.)

  8. Crop Tool: “Lock ratio” is on with every new use. Needs to be turned off for each new pic. Right?

  9. HSB changes to overall colour: I think I cannot just drag left/right on a desired colour in the photo to change the clicked value range’s hue/saturation/brightness? (Aware of Colour Equalizer, RGB Curves and Lab* Adjustments, but they don’t let you pick a colour range by clicking into the image and change it by dragging in the image, or am I wrong? With ART it’s a more technical approach, you need to decide on a colour range and drag a slider.)

  10. There is the right-side Panel “Transform/Lens-Geometry/Perspective Correction” AND above the image there is the tool “Perspective Correction”. Is it the same function? In both cases obviously I can draw “control lines” – but I never see them on pic, I am always just panning the image (as with the hand tool (arrow symbol)) (i have the “Perspective Correction” panel switched-on) . How to draw control lines, how to distinguish “Perspectiv correction” tool and panel? (I take it that “Select Straight Lines” from the Rotate panel is something different, merely to rotate, but not to correct perspectives such as converging lines.)

  11. Individual Masks per Tool: Each Local Editing tool has its own mask. If I wanted to apply local “Color/Tone Correction” and local “Texture Boost” to the same area, I need to create TWO masks, that’s why each Local Editing tool has its own Mask panel. Right? But I can copy-paste the masks, no need to create them anew from scratch.

  12. Can the masking brush follow object contours (as in “auto masking”)? Aware that parametric mask is a good help, too.

  13. In the tutorial you write:

“The image of the building is reasonably well exposed, but the near face is in shade, so we’ll lighten the shadows a little. Click and drag the Shadows control to the left and right to see the effect.”

– To LIGHTEN the shadows, you would drag to the RIGHT, or not? You also settle on “+30”, obv. dragged to the right?


answers inline.

No, there’s no difference between raw and non-raw files. In both cases, ART stores the edit in an .arp sidecar, and never overwrites the original. If you quit and restart, you should still find your edits and your saved snapshots. History is discarded on exit instead, as you correctly point out.

UI is currently available in English, French, Dutch, Spanish, Catalan, Japanese and (partial and a bit outdated) Brazilian Portuguese. There’s no German translation because nobody provided one :slight_smile:

From the file browser: right-click → “processing profile operations” → “reset to default”

From the editor:
Screenshot from 2021-11-08 15-15-30

Right. ART has no DAM, only basic file browsing

No, there’s only snapshots indeed.


You can set your own defaults for each of the tool, by using an appropriate default processing profile. You can also have different defaults according to the image metadata, by using dynamic profiles.

I’m not sure I understand the question. Can you elaborate?

Yes, just two different entry points.

You need to hold the Ctrl key while clicking and dragging lines.


I’m not familiar with how auto masking works, but the brush can be smoothed with the edge-aware “feathering” slider

Yes, but to me the sentence reads fine (note, I didn’t write it and I’m not a native speaker though).


I often process photos in both colours and b+w with many variations especially in the b+w with some kind of toning.

I just make sure that I save the sidecars with modified names: image-0111-colour.cr2.arp and image-0111-bw-01.cr2.arp and even image-0111-bw-02.cr2.arp… Then I load that specific profile when I want to further edit.

That’s how I do my “virtual copies”

BTW, if there’s a better or simpler way, please let me know because it’s something that I use on regular basis.


Snapshots are meant to be simpler.

Alberto and Foto-Syv, thanks for your replies! Alberto, thanks for all the details! Now I have a better understanding.


  1. I want to change only the blue sky. I open the HSB panel, activate “Brightness”

  2. I activate the Targeting Tool (?) and click within the photo into the colour that I want to manipulate. So I click into blue in the image itself.

  3. I drag to the right over the image to brighten the selected blue or to the left to darken the blue. The HSB sliders will move as I drag in the picture.

If wanted, I could then switch to “Hue” or “Saturation”, click into a blue part of the image again and drag on the picture left/right to change hue or saturation only of blue.

The important thing from my pov is not the dragging over the pic, but the selecting of the colour range (here blue) by clicking into that colour right within the pic (here by clicking into the sky), instead of clicking into a colour wheel or by choosing one of many sliders.

Oh… thanks…

That smoothing makes the brush edge-aware? I hadn’t realized it.

For example you have a mountain range with clouds behind the mountains. You want to select the mountains. It may be a little difficult to follow the mountains with a brush perfectly. But if you can turn on “auto mask”, the brush will exactly paint along the contours, paint along the mountain tops, and will not go “over the tops” into the sky.

So the feathering slider would do this?

I understand you can often get the same selection with a parametric mask and masks can be inverted. But sometimes it’s easier to just paint a mask into the pic – if the brush does follow contours automatically. It would be easier for instance if the mountain range and the clouds behind it have a big range of tones (difficult to catch with parametric mask), and it’s also a matter of personal style.

Thanks again!

Did you have a look at the colour equaliser? It should do what you described

Thanks - yes indeed, it’s about what i meant - you pick the colour value by clicking within the pic. I hadn’t realized this possibility to select a colour within the pic before.

Do the snapshots get stored in the arps and be available the next time around.

The rawtherapee doc says:


Yes (it’s written in the ART webpage, under “Features”)