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04 November 2009

Mit technischen Problemen ist zu rechnen

So geht's im Alter

Seit ich wieder angefangen habe mit der Arca-Swiss zu photographieren, sind mehrere technische Probleme aufgetaucht. Zuerst mal hab ich natürlich das Problem, dass ich keine Dunkelkammer habe und daher die Weiterverarbeitung meiner Bilder noch in den Wolken steht. Davon rede ich aber nicht. Das erste Problem war, dass beim 180er Objektiv (ein Schneider Tele-Xenar ca. 1954-57) der Verschluss bei den längeren Zeiten hängt. Zeit für einen Service.

Soweit so gut, die Beschränkung auf weniger Objektive fördert die Kreativität! Als nächstes stelle ich bei einem Ausflug zum Marathon-See fest, dass auch die anderen Verschlüsse klemmen, sobald die Umgebungs-Temperatur etwas niedriger ist. Mechanische Verschlüsse funktionieren sonst bis etwa -20ºC problemlos. Wenn sie schon bei ca. plus 5-10ºC klemmen, dann ist das ein Zeichen, dass das Schmiermittel im Verschluss alt und verharzt ist. Zeit für eine Reinigung und Neueinstellung.

Letzte Woche habe ich dann drei Farbnegativ-Filme entwickeln und scannen lassen. Zu meiner Freude sind ein paar brauchbare Aufnahmen dabei (Bilder demnächst), aber ich hatte auch eine weniger freudige Überraschung: Anscheinend ist bei einer meiner Kassetten eine der Verschluss-Sicherungen ermüdet. Das führte dann dazu, dass ich bei einigen Aufnahmen Lichteinfall hatte. Zum Glück nicht bei allen. Ich hatte konsequent die zweite Kassette für s/w benutzt, also kann ich noch hoffen, dass zumindest die schwarz-weiss Belichtungen was geworden sind.

Zwischen Verschlüssen die hängen und einer Kassette die wohl einen Bastel-Fix braucht ist mein Spielraum also leicht eingeschränkt. Mit einer Kamer diesen Alters muss man wohl mal ab und zu mit solchen Wehwehchen rechnen. Die Lust aufs Photographieren ist mir aber auch nach den ersten Resultaten noch lang nicht vergangen.


Posted by betabug at 09:23 | Comments (0) | Trackbacks (0)
07 November 2009

First Results - Akropolis in the first morning light

Got a few low quality scans
Athens Akropolis in the morning light

On the 21st of October, I had gone up Filopappou hill before sunrise, found my spot, waited for the sun to come out. Took several exposures in changing light conditions. This is the last one of the series. at 8:20, with the sun out over the Ymittos hills and hitting the walls of the Akropolis.

By clicking on the image, you can get to a flash "zoomify" viewer, with which you can zoom in to see as much detail as the cheap scan gives me. This is a really cheap scan (1.50 Euro for scanning 8 images). The largest size in the flash viewer is compressed a lot too.

Arca-Swiss 6x9cm
Schneider Symmar f=100mm
1/30sec, f:22-32
Kodak Portra 160NC

I have other exposures from the same spot and morning, from before the sun comes out over the Ymittos. This one where the sun reaches the walls of the "big rock" is the one I currently like best.


Posted by betabug at 15:13 | Comments (4) | Trackbacks (0)
10 November 2009

I didn't go

No picture today

Yesterday I had looked up the times and angles of the sunrise and the moon for this morning. It would maybe not be an ideal morning, but a good morning, to climb on the Lycabettus hill and take a picture of the city and the Akropolis in the sunrise, with the moon somewhere in the morning sky. Did I water your mouth with the description? Well, I didn't go. The weather report was not too sure. Before I went to sleep the sky was clear. When I got up at 6, I went outside and saw a sky with 80% cloud cover. I decided to go back to sleep.

When I finally woke up at 9, the sky was clear, except for a bank of clouds far off to one side. Too bad, no picture for me this morning. Yesterday my plan had been: Just go there and whatever happens, well, happens. This morning I was probably too sleepy to decide in this direction.


Posted by betabug at 09:21 | Comments (0) | Trackbacks (0)
18 November 2009

Catching Python xmlrpclib Exceptions

Don't you just like these?
 

When using Zope, you don't want to have bare "except:" clauses lying around [1] and when using xmlrpclib in Zope, you will have to guard against whatever connection trouble there may be. Problem is, xmlrpclib seems to sometimes report errors by raising some nonstandard looking exceptions that show up in a traceback like this:

error: (61, 'Connection refused')

Uhm, yeah. In order to catch "error" with a try-except, I should know where it comes from. Lucky me, the traceback mentions that this one is from:

Module httplib, line 630, in connect

Looking there, I see that the code is raising socket.error.

xmlrpclib also has a few errors of its own. I should decide which ones I want to catch, but in general I can do something like this:

from socket import error as socket_error
#... lots of stuff...
try:
    result = server.xmlrpc_update_address_company(id, data)
except (socket_error, xmlrpclib.Fault, \
    xmlrpclib.ProtocolError, xmlrpclib.ResponseError), error_code:
    handle_error(error_code) # whatever you do...

This will get most tracebacks off the back of my users, but of course now the burden of handling the errors is on me. That's the life of the programmer.

[1]because those broad "except:" clauses will also catch ConflictErrors, which Zope should be let to handle by itself. It's also bad style even in general Python.

Posted by betabug at 11:35 | Comments (0) | Trackbacks (0)
26 November 2009

Apple's Fooled Everybody With Address Book Server 10.6 Description

Read it, baby, read it real good!
 

So we upgraded to Mac OS X Server Snow Leopard 10.6 (can system software names get any longer?)... all nice and dandy. Starting up "Address Book Server", wonderful. Setting up Address Book on a Snow Leopard 10.6 machine to connect to Address Book Server to share an address book, then a second one to get the shared address book. But wait, something doesn't work... the 2nd Mac never sees the first's address book. What gives?

Re-read the description:

With the new Address Book Server in Snow Leopard Server, it’s incredibly easy to access and synchronize contacts across multiple computers and the devices you own.

Everybody on the Intarweb-thingy read this to the logical conclusion that you can set up an address book for your office group of people and people can share the addresses in that. But as has been pointed out in a couple of discussion threads that will probably soon disappear from Apple's support forums, the fine point is in the words you own. If you set up an address book with account "Adam", then only account "Adam" can share this address book, for example on two different Macs Adam owns. What people would have expected in a workgroup environment is that Adam can publish an address book for his team to share.

What you can do is make an account on the server only for use with the Address Book Server, then give that username/password to everybody for access of the shared address book. Crude. The other option is to set up a gateway to a LDAP "Global Address List" and go back to the big setup of LDAP.


Posted by betabug at 10:39 | Comments (5) | Trackbacks (0)
29 November 2009

Sunny November

3 degrees more than usual

People are swimming at the beaches around Athens and those who aren't going that far, still enjoy the sun. There's lots of sun, the metereologists say this November is 3 degrees warmer than usual.
I'm on a walk along the coast. Something I haven't done in a long while. It's nice to get some fresh air along with the sun, since the unnatural long streak of sunny and warm weather has let the air pollution levels rise high. Every day in the office, on the 7th floor, I can see the smog in the air.
Now I just look at the waves, hitting the shore like they always did.


Posted by betabug at 15:20 | Comments (0) | Trackbacks (0)