Howdy,

Most monitors are running at 72dpi, however there area FEW that run higher.

A lot has to do with what graphics program/scanner you are using to prepare the images.

I may be able to give you better advice when I know this.

One thing you can do to improve download speed is to remove as much as possible that isn't needed. For example in the scans above, does it matter to your viewers that this is a CGO 0273 - Commemorative? If not, crop everything down to the eges of the chip.

Scan #2 is slightly bigger than #1.
Scan #3 is about 20% smaller than #2.
Scan #4 doesn't have the same quality as the others.

Keep in mind that most computers only display 256 colors at one time. The exception to this is when there is a name brand graphics card built into the motherboard or someone has added on a graphics card. When you prepare images to be displayed it is better to either have them on different pages or have all the chips (images) together in the same graphic. If you get too many pictures all saved with their own color scheme on the screen at once, the computer will start to do funny things with the colors.

A few basics to remember:

Photos should be jpeg (jpg), png, tiff, or someother format.

Cartoon type pictures/logos/graphics are best in gif format.

Once you get your picture on your computer do everything to it before you save it in jpeg. Don't open it up again and then save it again. Everytime you do this with a jpeg (there are other formats as well) you lose quality. Most digital cameras save in jpeg, but some have the option of tiff. If you can save in tiff, then do so until you are done messing with the picture, then save it to jpeg for upload.