I downloaded a few 1992/1997 DOQQs for the Wickenburg area but I cannot figure out which year they were taken.  I know I'm supposed to look at the header, but these photos don't have .hdr files.

The photos are in the 33112/h folder, and only the first few photos in that folder have .hdr files.  Is it safe to assume that the photos I downloaded were taken at the same time as these others?  The photo year is very important to the work I'm doing, so I need to be fairly sure about this.

Thanks!