Digital camera question: We have 2 cams, one 3.2 mpxl and one 6 mpxl. Both produce jpg files of about 3Mb??

Question

Do not understand the relationship between megapixels and megabites.

Answer 1

Check several pictures before drawing this conclusion. You may have the 3.2 MP camera set at the very highest resolution and the 6 MP at the next-to-highest. The 3.2 MP camera might actually have a better sensor than the 6 MP camera does.

If there is not much data to store, the file will be smaller than the full potential size. If there is a lot of sky, for instance, or a large area of one color, the file will be much smaller than a very detailed picture would produce.

I just checked on a bunch of files I have from a 6 MP camera and found that most uneditted files with any detail were around 3 megabytes. Same check on an old 3 MP camera found files ranging from 1.0 to 2.0 megabytes, but I don't find any over 2.0 MB.

Some cameras produce more information per pixel, also. In highest resolution with minimal compression, a really top camera (Hasselblad) can produce 16 bits of information per pixel per color. (48 bit RGB) This will drive the file size way up. Many DSLR's save up to 12 bits per pixel per color. (36 bit RGB) A moderate quality camera will stick to around 8 bits per pixel per color. (24 bit RGB) It's conceivable that your 3.2 MP camera is saving more date per pixel than your 6 MP camera.

Answer 2

In general the more megapixels the more megabytes.

BUT

With photos generally stored as jpg, the manufacturer can vary the amount of jpg compression used so that a file with more megapixels is actually smaller. See if you camera has a jpg fine setting or something similar. If not can the camera take pictures in RAW mode?

If it doesn't do either of those then you are stuck with what you have got, unless you replace the camera.

Answer 3

Dr Sam has given you the answer. My Canon 300D (6.3megapix) stores jpg files of about 2.5MB to 3.4MB. So your 3MB figure fr the 6 mp camera seems right for jpg.

Do check the setting f the 3.2mp camera. If it s saving a jpg, it looks like it s dumping like a raw image - no compression.

Dont throw either cameras away :) (or better yet tell me where)

Answer 4

On my cameras you can choose the resolution of the photos you're taking. 640 by 480 pixels, 1024 by 768 pixels, and so on. The higher the resolution = the more memory being used.

Answer 5

Well I think megapixels are the amount of dots per square inch and megabytes are amounts of data. If you use any amount of pixel per megabyte it shouldn't matter. It only matters what your printer can produce per one square inch.