Why the 'number of photos left' is lower than actually how much can fit on card? - 1

I have a Nikon D200, and i'm using an 8GB CF card, and it says "886" for the photos left. But I recently did a shoot, and I got well over 1, 200 photos on the card, and it still said "308" left.

Does anyone know why this is?
Is there anything I can do so I can get a more accurate number of photos left I actually have?

Added (1). Oh yeah, and I shoot in Large JPG almost all the time.

Depends on the resolution of the pictures you took.

Typical nikon behaviour. It looks at the amount of free space and your current settings and presents you with an absolute worst case scenario. Nothing you can do about it.

The remaining photos left is only an ESTIMATE. It is the same with any camera and memory card. Each photo you take, no matter what size / format you use, is not the same file size. Photos vary in file size depending on how "data intensive" the photo is. In other words, a photo with a vast amount of colors will be a much larger file size that a photo of a black piece of paper. So the photos remaining will NEVER be a fully accurate number. The camera can only estimate this information. Sort of like the miles remaining readout that some cars give you. It is an estimate based on current driving conditions. Vary those driving conditions, and your milage will vary greatly. Same with your camera. Your photo file size can vary greatly from shot to shot, and that will affect how many photos you will get on the card.

Cos that is an estimation…

Have you ever looked at the size of your images in Windows Explorer and seen that while they were near the same size, they were all over the board as well? Ever wonder why? In digital photography the more color and detail in the image the more of the maximum memory that image is allowed to have, is used.
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Example… Shoot a cloudless sky, save it. Shoot a pic of the back yard and save it. Now, in your computer look at each of the images on your computer and see how much memory they take. The sky pic will have the less…
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Because of this, there's no way in heck anyone can say you have a exact number of pics left on your card and the number given is just a estimate. The make of the camera is also not a plus or minus here.