December 28, 2010

Determining my most used focal length in photos with python and dcraw

For the holidays I got a new Canon 7D camera. I’ve been saving quite a few amazon gift cards over the last year that I was previously planning on using towards purchasing the camera but thankfully Santa delivered me one. My current lens collection consists of

10-22mm f/3.5-4.5
70-200mm f/4
50mm f/1.8
18-55mm f/3.5-5.6 (kit lens) The lens collection has been built over the last 4 years from when I first got my Canon Rebel XT and I’ve been fairly happy with them thus far. As part of looking into what new lens to get I wanted to know what focal length I shot with the most over the previous years. A quick look with

find . -type f -name '*.CR2' | wc -l

shows I have 4697 RAW images in my photos folder, so I’ll need some sort of automated solution to figure this out.

September 26, 2010

Python pip on Ubuntu Lucid Lynx

Lately I’ve been reading up on Django a bit in an effort to get back into programming. It seems the preferred way of running Django is inside a virtualenv environment. I try to stick to packages when possible for installing applications and saw that the python-virtualenv package wasn’t too far behind at version 1.4.5, where the latest is at 1.5.1. This appeared at first to suit me just fine until I discovered the version of pip that gets installed along with python-virtualenv is at 0.3.1, where the latest is at 0.8.1. The version of pip installed is so old that it doesn’t have support for the “uninstall” command yet, blech. Luckily you can do the following from within pip to upgrade itself

August 14, 2010

Configuring Varnish

At $WORK I’m currently working on deploying a pool of Varnish servers to sit in front of some Apache servers running Pressflow. On our current infrastructure we’ve been running Squid for the past few years with very good success , minus a hiccup or two along the way, one involving memory fragmentation (thank you tcmalloc). Varnish has a few nice features that Squid lacks.

The ability to PURGE objects using wildcards
Better support for multiple processors (Squid can benefit from multi procs when using AUFS)