D300s SDHC card capacity
I just received my D300s this week and I'm seeing something curious about how many images the manual and camera tell me a card can hold. I see in the manual that the average size of a 12-bit losslessly compressed RAW image is about 12MB, and I can confirm that from my tests. It also says that a 4GB card should be able to hold 197 of those images, which multiplies out to just 2.5GB. Sure enough, my camera, with a 16GB SDHC card, says that it can hold only 795 images, coming out to 10GB. I can understand that they want to be conservative, but sheesh!
If I pop the 16GB card into a card reader, it says that there's just about 16GB free (using 1GB==1000000bytes). It's really empty, and really a 16GB card. When I first saw the discrepancy on my camera, I figured that I'd configured a setting in a strange way. Now that I see that my numbers sync up with the manual, which assumes "best case" settings, I think they're simply using fuzzy math.
As I was shooting today, I could see the number "correcting" itself periodically and not decrementing for every shot, so I have every reason to believe that it'll actually fill the card. It just feels like somebody setting their alarm clock 30-60 minutes ahead to make sure that they get to work on time.