Memory card image numbers

[Frog]

Wasn't sure where to put this or what to title it.

I took 278 pictures today on a Lexar 2 gig sd card. I saw at one time that I had 77 pics left on the card at one time but was clicking away everywhere today and didn't pay attention to when the counter got down to 0.
When I put a formatted 2gig card in my D80, it tells me I have 265 images that I can take.
That's in raw mode.
I know it has happened before but it really stood out to me today. Has anyone else had this experience....getting more images than the card/camera say you can?

[mjs1973]

I think it's pretty common for the # of images that will fit on a card to change. Not all images have the same amount of detail and not all images take up the same amount of space on the card. The # the camera says you have left is really only an estimate.

[Anbesol]

On the D200 at work, it will almost always start out with 446, but it will deplete much slower than the number of images obtained, so I'll take say 15, and it will say 438 left. Of course, the variable is greater with jpeg.

[Frog]

Just wondered if it was common. Still not sure why one pic needs more room than another but just knowing that it happens is enough for me

[mjs1973]

Just wondered if it was common. Still not sure why one pic needs more room than another but just knowing that it happens is enough for me

An image with a lot of detail is going to need more 1's and 0's to store all of that info. Compare that to an image with a huge section that is over exposed and blown out. There isn't any info in the blown out areas.

This brings up something else that you should be aware of. Trying to add more info to a card than it can hold can be a cause for having problems with the card. It may lock up the card or cause it to fail. I always try to switch out my cards before I get down to only a few images left.

[OldClicker]

An image with a lot of detail is going to need more 1's and 0's to store all of that info. Compare that to an image with a huge section that is over exposed and blown out. There isn't any info in the blown out areas.

Is that true for the RAW main image? (Nikon doesn't use compressed RAW, do they?)The rendering software still needs to know if it was 255 or 0. I can see that there could be a big difference in the embedded jpg, but not the RAW itself. - Terry

[mjs1973]

Is that true for the RAW main image? (Nikon doesn't use compressed RAW, do they?)The rendering software still needs to know if it was 255 or 0. I can see that there could be a big difference in the embedded jpg, but not the RAW itself. - Terry

Take a look at a bunch of RAW files you have on your computer and compare the image size. You will see that they change quite a bit depending on the image. See the screen shot below. There is a full MB difference between the 1st and 3rd images but the scene is virtually the same. The exposure is different and one has a bird in it, but the file sizes. It didn't take much of a change in the images to make a noticeable change in the file size.

[Frog]

Thank you, Anbesol, MJ, OC. I seldom take that many shots but will watch closer so as not to overload the card and switch it out before it does