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Digital Image Basics for non-Photographers • Blaise Tobia
More on Optimum Image Size
One issue in sizing images for submission or portfolio use is that of horizontal vs. vertical format.
The entire digital image system favors horizontal images, in that most displays use a horizontal format.
(And, with the move to widescreen formats such as HD Video, this is becoming increasingly an issue.)
If maximum allowable screen space is used, then horizontal images can be sized substantially larger than vertical images.
Here are examples based on a standard 35mm photo, which is 3x2 in format, in a Powerpoint slide.
(More on Powerpoint follows.)
Some artists prefer to use the same size for both horizontal and vertical images, within a filled maximum square boundary.
Either way, keep in mind that multiple images may be projected simultaneously, meaning that each image may be relatively small.
Aim for images that look good even if seen in a relatively small form.