How is it possible to make a 18 m.p. Picture with a canon t31 slr?

[welded]

Forgive a newbie but when I set my t31 camera to either raw or the highest jpeg settings, the saved pictures properties indicate that the picture is only  5 m.p.

The camera is rated at 18 mega pixil...What gives?

[rchalfan]

Jpeg is a compressed format. The camera firmware makes "intelligent" choices to maintain maximum image quality within the 8 bit dynamic range of the jpg file. The exact size of the file will depend on the image itself but will be in the 5-6 MB (megabyte) range when your camera is set to the highest jpg quality. 

Raw files, on the other hand, are minimally processed and the saved file will be around 24MB. If you are seeing 5 MB files from what you think is raw, you may be looking at the .jpg file if you set Raw+jpeg. Otherwise I suggest you check the menu "Image recording quality" setting again as it may not be set to Raw.

Recall as well that the file name of a raw file ends ".cr2" while a jpeg file name ends ".jpg".

[cicopo]

MegaPixels are NOT the same as MegaBytes. The explination above should clear the file size error up re your thinking the 2 are one in the same.