The biggest reason I bought it is the full frame sensor The sensor is what the light hits and makes the image on instead of a piece of film. For those of you who aren’t photogeeks, my old Canon 20d had a digital sensor was 2/3rds the size of a standard piece of film. This meant that I had to do funky calculations on all my lenses. A 30mm lens on a Canon 20d and other DSLRs with smaller sensors actually performs as if it’s a 48mm lens. A 100mm lens acts as if it were 160mm. You seriously impair your lenses ability to go wide when you have a camera with a undersized sensor.
Wider lenses are generally quite expensive and by buying the 5d and getting a full frame I am essentially maximizing the value of the nice lenses I have; the Canon 50mm f1.4, the Canon 24-70mm L f2.8, and the Canon 70-200mm L f2.8.
More interesting for most people probably are some of the secondary reasons why I bought it, namely Italy and China. I’m going to be doing a ton of traveling this year and now seemed to be as good of time as any to make the upgrade.
Other things worth noting are the increase in megapixels, from 8 to 12. I’m also excited to expirament with the expanded array of ISO settings including 50 ISO and lots of other lil incremental changes. It has a significantly larger LCD screen on the back which is brighter too. Ok ok, enough talking about the fancy new camera… I feel like I’m getting carried away. 😛 Scales picked up my old 20d and the battery grip. It’s been a great camera, it saved my life, and I’ll miss it but I know it’s in great hands and is going to see some amazing sights. 🙂