GIMP / darktable / FreeCAD / Ardour Weekly recap — 12 October 2025

Week highlights: new releases of GIMP and RapidRAW, new features in darktable and Ardour.

GIMP 3.0.6

This is purely a bugfix release, don’t expect anything new. The release notes are here.

darktable and AgX

The team recently merged a patch by Kofa that adds AgX, a new tonemapper originally seen in Blender. This is not the first photography app to use AgX (Saulala is likely the first one), but definitely the most prominent one so far.

There have been several general tonemapper modules before AgX: base curve, followed by several variations of filmic (later renamed to filmic rgb), followed by sigmoid. I specifically do not mention other tonemappers here, as they were intended for use elsewhere in the processing pipeline.

Rather than emulating the film look, AgX aims for colorimetric accuracy and better chromatic consistency across the dynamic range. Kofa explained the mechanics of AgX in darktable early on in a thread on Pixls, I think you should read it if you are interested.

The module has controls for the input data, base and advanced curve parameters, and the look (slope offset, power, saturation, hue preservation).

AgX in darktable

My personal impression so far is that while AgX provides a lot of control, just like with other tonemappers, the defaults are not great.

On scenes with a wide dynamic range, details in highlights get flat, shadows/blacks get even darker, and hues change regardless of how much hue preservation you apply in AgX settings. Sigmoid and filmic rgb do a similar thing, but at least they don’t touch hues as much.

So, I guess, we’ll have to continue tweaking tonemapping settings quite a bit for the foreseeable future to get to a decent baseline.

RapidRAW 1.4.2

Timon Käch released an update of RapidRAW with several quite useful improvements:

  • The Highlights slider doesn’t dull the image as much as it used to
  • The Exposure slider doesn’t oversaturate and overexpose as much as it used to
  • Exports now can have optional controllable watermarks

Pink highlights and watermark UI in RapidRAW

Unfortunately, as you can see, the recent fixes have not improved the situation with pink in overblown highlights.

Nevertheless, here are the usual downloads and release notes.

FreeCAD

A year ago, Paul Ebbers picked up the SearchBar addon, originally created by Suzanne Soy, and started improving it. This is what you know from applications like Blender, GIMP, Olive and probably many others. Paul now proposes to include it in FreeCAD 1.2.

SearchBar in FreeCAD

There’s also a pretty substantial patch by tarman3, adding numerous Array command improvements in CAM. It’s currently in draft and will likely be merged for v1.2 as well.

The release blocker needle is slowly moving towards zero and is currently at 27 remaining blockers. It may take a few more months to go all the way left.

Ardour

Robin Gareus investigated the StaffPad’s audio stretcher now used by Audacity, found that it works better than Rubberband in some cases, and added it as an “Any” option in the Time Stretch tool.

New timestretch option in Ardour

Mixer channels now have an RTA (real-time analyzer) toggle:

RTA toggle in Ardour mixer channels

Finally, Ardour now has support for the iCON V1-M controller, contributed by one of the Mixbus developers.

iCON V1-M option in Ardour

MIDI CC & NRPN database

This is a recent find of a not-too-recent project. Ben Fox started working on a database for MIDI CC & NRPN of various hardware synths, samplers, etc., and 24 contributors joined over the years. If you have one of the supported devices and need to control it from the DAW, this may come in handy.

All the information lives in CSV files on GitHub and is available under the terms of the CC-BY-SA-4.0 license. You can contribute new descriptions to help make the information more discoverable for other users.

Artworks

Silent Sunday artwork by Sylvia Ritter, made with Krita:

Silent Sunday artwork by Sylvia Ritter

The Old Tibetan monastery by Maxim Petrov, made with Blender and Photoshop:

The Old Tibetan monastery by Maxim Petrov

Tale’s Edge - Snowy Woodland Village by Andy Walsh, made with Blender, 3DCoat, and Photoshop:

Tale’s Edge - Snowy Woodland Village by Andy Walsh


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