With FotoFinish you can easily print a 4x6 photo using the standard photo size templates. If you use the Photo Wizard, you don't need to know anything about resolution to print your image. Simply pick a template and print. To learn more about how to print using layouts, including standard size photos, read the Printing Your Images section.
If you want more control over print quality and size, you can use a simple formula to calculate the resolution you need for any given output.
A 2
megapixel camera can easily create a 1600 by 1200 pixel image. You can print
this image at a number of different sizes determined only by resolution. Take
the length of the image in pixels and divide it by your target length in
inches. The result will tell you what you need to set your resolution to:
1600 pixels / 11 inches = 145 PPI
1600 pixels / 10 inches = 160 PPI
1600 pixels / 9 inches = 177 PPI
1600 pixels / 8 inches = 200 PPI
1600 pixels / 6 inches = 266 PPI
1600 pixels / 4 inches = 400 PPI
1600 pixels/ 2 inches = 800 PPI
As your target print area decreases, your resolution increases. In general, you
can get a good, photo-quality print at 200 PPI or above. However, what
constitutes photo quality is highly individual and subjective. It's a good idea
to experiment with different resolutions to find your tolerance level.
Once you’ve set your resolution, you can print your photo at its actual size using either the Landscape or Portrait template under Simple Layouts in the Print Wizard.