personal reminder: Convert Nikon NEF to JPG with ufraw

$ ufraw-batch --out-type=jpeg --out-path=/home/itsme/Pictures/export --compression=85 --size=1280 /media/Data/home/itsme/Pictures/MyPics/*.nef
for more details cf.

howto copy CalendarServer (content) - use rdiff-backup

rsynced a complete and functional copy of CalendarServer to another drive (and to another file system). afterwards, the server started and didn't complain but didn't show any calendar (but still logged in and didn't complain about anything - just no calendar!).tryied rsync -aA, rsync -rlpAtgoD (long version - one never knows...), and cp -a - but all to no avail.finally, i tried rdiff-backup -b - and this worked... why?

personal reminder: building debian packages from source

...for future reference:
  1. apt-get source (-t testing) PACKAGENAME
  2. apt-get build-dep (-t testing) PACKAGENAME
  3. cd PACKAGANAME-version
  4. OPT: vi debian/rules (e.g. to activate some experimental features)
  5. OPT: vi debian/patches/00list (to enlist a patch that should be applied)
  6. OPT: vi debian/patches/...

apt-listchanges chokes on its DB (bsddb.db.DBRunRecoveryError)

in case of:
Traceback (most recent call last):File "/usr/bin/apt-listchanges", line 229, in ?main()File "/usr/bin/apt-listchanges", line 150, in mainseen.close()File "bsddb/", line 237, in closebsddb.db.DBRunRecoveryError: (-30974, 'DB_RUNRECOVERY: Fatal error, run database recovery -- PANIC: fatal region error detected; run recovery')
(similarly to the post below) something along the lines of:
cd /var/lib/aptdb4.6_dump listchanges.db | db4.3_load temp.dbmv temp.db listchanges.db

Photogenic science

Science looks better in pictures.

The unfathomable of the wise

The unfathomable to the wiseIs the obvious to the dimwitAnd vice-versa.Who is who?

Psychology of Scales

The machine that will solve all the mysteries in science was inaugurated.The Cern is there, up and running.You may ask a question about the nature of the universe.The New York times informs that the particle collisions that will answer that question require about 5 trillion electron-Volt. 5 Trillion.Now. As a mechanical engineer I had to make the conversion to a unit that makes more sense to me. Like the Watt/second (W/s), or Joule.5 10^12 / 1.6 10^-19 = 3.125.10^-7 JThat is, not that much energy, in fact.

Rainer von Vielen - Sandbürger

Super Track! Ich wuerde auch ganz gerne mit einer solchen Stimme singen koennen. Doch leider schrottet man sich derbe die Stimmbaender wenn man das uebt….

How many spikes in a J

A do-it-yourself experiment:Question: How many action potentials (spikes) fit in a 'j'?Step 1. Type the 'j' key (any key will do, really, just as long it produces a character. Shift, for example, does not), with one finger, in the editor of your choice, in intervals of t seconds, in this case t=4s.Do it as fast as you can. (It is in principle not necessary. But in that case, in the end of the calculation you find the minimum number of spikes per jay.