If you import a georeferenced image into MapViewer that contains projection-specific information, the image is projected in the map window. It is also possible to change the projection of a image with the Map | Convert Projection command. However, there are certain limitations that apply to projecting bitmaps. The recommended maximum bitmap size for projection is 5000 pixels in the longest dimension. If you try to change the projection of a bitmap that is larger than the recommended size limit, the resulting bitmap will likely contain some distortion and loss of resolution.
The bitmap projecting process requires a very large amount of memory. Here is a rough memory calculation (in bytes): width resolution x height resolution x 3 x 2.7. For example, a bitmap with the resolution 5000 x 6000 requires 5000 x 6000 x 3 x 2.7 = 243000000 bytes (about 230 MB) of extra memory during projection .
To disable the ability to project bitmaps, go to Tools | Options and check the Do not project bitmaps option. This option is useful if you have large bitmaps (>5000 pixels in the longest dimension) in the map window and you do not want the bitmap to become distorted or degraded. It is also recommended that you use this option if you have bitmaps in the map window that compliment the map layout (such as a company logo). When the Do not project bitmaps option is enabled, these bitmaps are not projected when you change the map projection.
See Also
Characteristics of Projections
Latitude and Longitude Coordinates
Latitude and Longitude in Decimal Degrees
Using Scaling to Minimize Distortion on Latitude and Longitude Maps