kbytes and more kbytes

[FJDBart]

Ok, I simply dont understand pictures kbytes sizes...

Why when I take the same pictures using 3 different cameras with the same image quality 3.0 megapixels I get 3 different pictures sizes..

First : Kodak DX6340 zoom
2032 x 1536
jpg
3.0 megapixels
file size: 321kb

Second : Fuji Finepix S5000
2048 x 1536
jpg
3.0 megapixels
file size: 832kb

Third : Canon Digital 300d REBEL
2048 x 1360
jpg
3.0 megapixels
file size: 1,82Mb

All pictures were taken in the same position with the help of a tripod, built in flash, exposure.

thanks
Fernando

[Hellashot]

It likely comes down to compression. Some cameras offer 3 different compression factors for each image size. You don't need to worry about how much an image is compressed if you never want to print the image.

[robertwgross]

Yes, compression is the answer. I'll go further. The more basic digital cameras often turn up the compression rate to be more serious. The basic consumer gets lots of images stored on his one little memory card. Often, the basic consumer is not all that "consumed" by image detail.

As you move up into the serious consumer cameras, sometimes the compression is less. So the image files are bigger, but there is slightly more detail.

Eventually, as you get up into the big cameras, they may have JPEG, but they also have RAW, and RAW images are used extensively in the serious game. This takes a lot of memory cards, but memory is cheap these days. Once the serious player has edited his image, he can do a final save in TIF or JPEG, and JPEG compression rate can be chosen to suit the mood.

---Bob Gross---