Your camera should tell you in the display how many images you can store on your card. Look for it, maybe in the user's manual.

The number should change accordingly if you change the resolution.

I get about 350 images, jpeg fine mode and 10MP picture size on a 2GB SD memory card.

Don't use TIFF mode, it's useless, unless you plan to use the data in a commercial printing process.

I don't suppose you wold shoot in RAW either, you'd have to convert you image data into a compatible format on your computer with designated software.

Reminder!!
Jpeg reduces the image resolution everytime you open the image for editing and save it again.

Here is what I do:
After transferring all images from a trip or any other event to the computer, I burn them onto a CD/DVD ROM. This way I can do what I want with the images on the computer, I always have the original to go back to.

Also, when you archive images you can rename your edited image differently from the original before you save it, this way the original will stay as it is, instead of replacing the original with the edited version.

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