Just for the heck of it, I barrowed the Canon EF 28mm f/2.8 lens from work tonight for a local classic car club get-together. Anyway, I had both my batteries fully, freshly charged when I got to the show. After only about 15 minutes or about 30 shots, the display on my 10D was showing the battery as being almost dead! I switched it out and put in the other fresh battery. The same thing happened again!
Now keep in mind, I only used the pop-up flash for maybe 3 or 4 images. Other than that, I was just using available light.
When I got home, I charged one of the batteries. This gets weird here too. The battery only took about 15 minutes to fully recharge! After that, I put it back in the camera, and within a few shots, it was showing dead again. So I put the other battery back in the camera without recharging it, but now with the 50mm f/1.8 lens mounted. The battery was reading a full charge again, and lasted for well over the 200+ shots I took around the house, all with the flash on at all times! It's still going strong as is the other battery.
Obviously, there must be some kind of issue with that 28mm lens and the 10D body. Has anyone else had this problem? Or does anyone know what the problem might be? I'm just curious about it.
Thanks

