I've been an amateur photographer since my early teens, but only recently started using DSLRs. My wife recently acquired a D40 and just last week I bought a D3000. I've asked this question to Nikon via their website support, and am still trying to get a reasonable answer.
For reference, I am using a PNY 4GB SDHC card in my camera, it is rated as a Class 4 card.
My question is this, what should my buffer capacity be? The manual is not clear, and seems to indicate that the buffer should hold 100 photos in any of the JPG modes, and just a few RAW images. My buffer capacity seems inconsistent with that, and in fact, makes no sense to me at all. Below is the buffer capacity (as reported in the viewfinder as rXX) for various shooting modes.
Image Size Quality Buffer Size Image Size (MB) small basic r47 .5 small norm r26 1.0 small fine r16 1.9 medium basic r19 1.1 medium norm r14 2.1 medium fine r11 4.1 large basic r16 1.9 large norm r11 3.7 large fine r08 7.2 large RAW r06 16
All measurements made with D-Lighting turned OFF and Noise Reduction OFF. Camera in "P" programed auto mode. If I turn the dial to Auto-No Flash the numbers typically drop, I assume this is because lighting may be poor and the camera figures it needs to do automatic noise reduction.
Just taking the last two values in the table above, one would expect that if 6 RAW 16MB images will fit in the buffer (6x16=96MB) then roughly twice as many large fine 7.2MB images would fit (actually 13 should fit). If you calculate all of these out, you get a different total size for each setting. Is it a processing time issue? The JPGs need processor time to compress and therefor fewer can "effectively" fit in the buffer?
Ok, sorry for the long post, the engineer in me coming out.