digiKam workflow for proper renaming

Written by  on December 28, 2020
  1. Import the directories with the images. Takes usually several minutes for gigabytes of data.
  2. Press F2 for renaming. Use as scheme:
    Self-explaining and with a unique three digit suffix in case two identical filenames would appear. → “20200216-141529_001.JPG”

robocopy: transfer huge repositories between PCs

Written by  on April 16, 2018

Average rates of 24% on 1 GBit-connected PCs with SSD were achieved! 🙂


my favorite parameters:
/NP – no status
/E – with subdirs
/MIR – mirros (like /E with /PURGE)
/MT – multithreading
/XD – exclude the subversion-metadata

resulting command

note: multithreading with 32 threads was slower than with just 8: 10 min vs. 7 min for 18 GiByte files of varying size



Written by  on April 3, 2018

Small program to pick out the best shots of the vast amount of taken pictures per session (excursion). The name itself is a wordplay of the plant Calendula and the activity “to cull” (slang for sorting the photos).

url for the repository:
development time for fully usable version 0.1: one day
used technologies: C++ and Qt – my favorite ones <3

Catcam upgraded!

Written by  on March 13, 2018

Terminator is watching you!

Finally! The old catcam-setup of a RPi 3 with a NoIR v2.1-camera was working for almost one and ahalf years without any issues. I’ve had improved the PiCamGifForTumblr-script several times, also changed location – never any issues. More than 40.000 GIF were uploaded.
But then I decided to buy a new, fancy case in black (of course) which should add some camera-support. And then two weeks afterwards it stopped working. Sporadically frozen. Sometimes 10 min after start, sometimes during the night. I checked the casing, if all power connectors were tightly fit, I installed netdata on it, I did longterm temperature-measurements (never over 54 °C even with closed case), I ran with minimal setup or with cam attached.
Then it became clearer: the camera was working for singleshot-mode, but for the 30 pictures every ten minutes, it broke. So, it was time to order a new camera, 1080p (5 MPixel) were enough, but for four more Euro I could get two IR-illuminators … so, why not? The focal distance of the objective is adjustable, it looks like it works (long time-test needed). But I am happy. And we can watch cats (and family) in darkness :3 convert all negatives via negfix8

Written by  on April 15, 2016

reason: too lazy to call the negfix8-script for each file itself. Because conversion is fast but even with an SSD writing the ~120 MiByte files takes some time. Precious time ..

ps. ‘do eis’ is latin, not some german-english mumble jumble.

Applied science ;)

Written by  on July 31, 2015

From time to time I develop some filmstrips with C41-chemicals. The data-sheet gives already some valid combinations of time/temperature, but it was lacking the one for 30°C.
I put the filmstrips for 8 min into the tank with the old Tetenal-kit. But what about the Digibase one? Linear interpolation would be not sufficient.
So lets take the sampling-points from the datasheet and do some cubic fitting (polynomial degree one less than the amount of samples).
And now what? Compute it myself? Hell no 😉
Et voila (thank Stephen Wolfram).

Fitting also shows no oscillation: good.

By the way: 7 min 30 s would be the correct time!