Just so we are clear about a few terms. There are three different types of graphics or photos availble through the software.

The first is your avatar and profile picture.
These are limited in size to 100 x 100 pixels and a total size of 65535 bytes.

The second is photos posted to threads.
Because these are not stored by the software you must have them stored somewhere on the web be that your own website or one of the photo hosting sites.

The final is photos uploaded to your personal albums.
These are limited in size to 600 x 600 pixels and a total size of 80,000 bytes.
You may have up to 100 photos in your album with a total size of 512,000 bytes.

For best viewing it is highly recommended that before you post a photo to the forum that you run it through a photo resizer/editor to get just what you want.