Does that First Image at Ancestry.com Give Clues?

When using databases at Ancestry.com sometimes the source citation leaves something to be desired. With digital images at Ancestry.com sometimes looking at the first image will give you an idea of where the actual records came from. Not always, but sometimes.

This image is from a database of Appointments of U. S. Postmasters, 1832-1971.  The source at Ancestry.com is not too specific, but the first image provides sufficient detail for me to craft a better citation than the one provided on Ancestry.com.

The problem is that not all image databases at Ancestry.com are set up this way.