The ideal image size for horizontal logos is 150 x 540 pixels. If your image is longer than this, the documents will automatically resize it length wise to 540 pixels.
If your image is square or not as wide as the size above, Finale will automatically resize it to fit properly on all printed documents.
Optimized constraints:
150 x 540 Pixels
0.5 x 1.8 Inches
60 x 216 Points
1.27 x 4.57 Centimeters
To learn more about resizing an image click here: