I have a Mac with OS X 10.7 and a load of photos from different sources with different names that I want to rename in a consistent manner related to the time and date they were taken.

Any suggestions for an App? Ideally free but will pay a bit if it is worth it.

I know I could do it in Automator but feeling lazy!

I used Hazel to do just this. It was a few years ago but pretty sure they offered a months free trial so it was free.

From the command line >>

Exiftool is a set of binary files that can be downloaded from:
http://www.sno.phy.queensu.ca/~phil/exiftool/

On a Mac I wrap the following line in a .sh (shell) script but can easily be done in a .BAT file for windows.
exiftool “-FileName<CreateDate” -d “%Y_%B_%d_%H_%M_%S.jpg” *.jpg

When this is run on any folder containing .jpg’s it will change the file name from:
IMG_0087.jpg to 2014_October_14_10_09_57.jpg

effectively renaming it to the second it was taken.

To shift by 5 hours and 30 mins it would be >>

exiftool “-DateTimeOriginal+=0:0:0 5:30:0” filename.jpg

A negative shift by one day would be >>

exiftool “-DateTimeOriginal-=0:1:0 0:0:0” filename.jpg

basic renamer built into the OS?

select items and ctrl click to get rename x items option

Lyn is nice as a paid option with more tools

I’d just do it in Automator, it’s not for the lazy but very powerful once you get it set up :p

+1 well worth spending an hour or so learning how to use Automator. One of the best things about OSX (along with AppleScript) but few people seem to use it (or are even aware of it!)