I work for Red Hat on the Fedora Linux distribution. Before that, I was a sysadmin in the Academic Computing group at Harvard School of Engineering and Applied Sciences. Photography is a hobby, and my main goal is simply documentation of my family life.

For some reason, most of my favorite answers here have something to with the geometry of photography, whether in composition, in exposure parameters, or angle of view. And hopefully in a way that makes it clear and interesting even to the non-geek:

• What is "angle of view" in photography?
• What historic reasons are there for common aspect ratios?
• What is the "exposure triangle"?
• Do flash guide numbers assume some amount of ambient light built-in?
• What is the 'Golden Ratio' and why is it better than the 'Rule of Thirds?'

But it's not all geometry!

• Is there development in the world of lenses?
• What are the key photography-related features from Photoshop that are missing in GIMP?
• What characteristics make a lens good or bad?
• Is it worth using Pentax's Premium JPEG quality setting?
• Are color and tones in this seascape fine?
• What does it mean for a photograph to be "high key"?

If you're a Pentax user, you may be interested in my definitive guide to Pentax hot shoe flashes and compatible 3rd-party options. It's no longer updated, but still has lots of good information. (If you'd like to take over, let me know!)

— Matthew Miller