New videos Wednesday at noon

Compositing with Darktable

Extend Darktable’s functionality by compositing with the watermark module

In this video tutorial I look at compositing with the watermark module. The procedure is simple but powerful. Here's how it works:

Darktable's watermark module allows you to overlay an svg file on the current canvas. I find 8mb to be the current upper limit on the file size of the svg in order for Darktable to import it properly. A bitmap image can be converted into an svg file by using inkscape like this:

inkscape -f filename.jpg -l filename.svg

It's that simple. The svg file needs to be located in

.config/darktable/watermarks/

Blending can be accomplished with the usual suite of blending operators (drawn and parametric).

* note: in this video I use the Raw black/white point module... but that is probably not a good idea. The exposure module is the much preferred solution!

The RAW file used in this video is available here. Thank you fatdunky for the contribution 🙂

1 Shot HDR

Quick rundown on various methods of adjusting tone and color in Darktable. Then a sneak peek at my 1 shot HDR technique.

In the video I start with a quick survey of different Darktable modules that you can use to set exposure, gamma, color balance and saturation.

With this week's Edit My RAW I get to use an experimental technique I'm working on for challenging captures. It's a lot like a single shot HDR, but with a wide range of applications. The enfuse command line I use in this video is:

enfuse-mp -o hdr.tiff –exposure-weight=1 –entropy-weight=0 –saturation-weight=0 * 

The RAW files used in this video are available here
Farmer's Market
Mountain in the Distance

Thanks Juan for the RAW contribution and your translation work. Find Juan's blog here

Ocean Entry Lava Video

Video processing with Darktable

Thursday evening I hiked down to the lava’s ocean entry. This video was shot at 24fps 1/50sec 100mm F/2.8 ISO 400.

I split the AVCHD file into png frames using

avconv -i 00000.MTS -ss 20 -t 40 -r 24 -f image2 %04d.png

-i 00000.MTS: is the filename
-ss 20: start at 20 seconds in
-t 40: end at 60 seconds in
-r 24: originally recorded at 24fps
-f image2: needed for png output
%04d.png: 4 digit zero pad output file names

Then I uploaded one of the frames into Darktable and did 2 passes of editing.

Lowpass, Highpass and how I use them

What is the difference between Darktable’s overlay and softlight blend modes?

Overlay adds contrast and softlight is a more gentle version. In this video tutorial I dive deeper into the questions I get asked most often about how I utilize Darktable's lowpass and highpass modules. I show different effects realized by combining them with overlay and softlight blend modes.

After the discussion and examples, I get to edit a contributor's RAW file. Thanks Sergei for the beautiful shot to work with.

Here is the link to the Darktable.org blog post "Using lowpass filter to recover shadows"

The RAW files used in this video are available here
Lava Steam
Flower
Vineyard