I recently got quite a few photos that all have the date and time set wrong and would like to correct it in the EXIF data before importing them into iPhoto. Anyone know of an application or script that will let me add X days and hours to every photo?

http://www.sentex.net/~mwandel/jhead/

Was searching for the wrong things in google at first. The above tool did what I needed, might be handy for others too.

Thanks! I think I posted about this exact same thing on here before but wasn't able to find a good solution. Thanks for finding the program, I can't wait to try it out!

To give a quick usage example, this command added 10 days to each photo:

./jhead -da2007:03:08-2007:02:26 *.JPG

3/8/07 was the date one of the photos was taken, but the data in the EXIF said 2/26/07. This also fixed some photos from the same memory card that said 12/14/06 instead of 12/24/06.

And this command added 10 hours and 2 minutes to each photo. Looks like the camera uses 24 hour time, but when it was set the person didn't realize it. The 2 minutes was to fix the drift it had, conveniently one of the photos had a picture of a digital watch in it.

./jhead -ta+10:02 *.JPG