Ok so, I was there, trying to assemble pictures taken at my sister's birthday. I have my pictures, her boyfriend's pictures, both have more or less the same date sor pictures have the same timestamp. Then comes another friend, which camera isn't at all at the same time. It's +/- 6:43 hour lead. And there is the mess, because I want all those pictures sorted by time, so people looking at them doesn't have to sort them himself. He just clic "next" and the next photo appears, whoever has taken it.

Now, I want my pictures sorted by time and gallery knows how to extract the time for EXIF tags, so I don't have to set the modification time of the files accordingly. But what to do when even EXIF tags are wrong ? I just discovered exiv2 adjust option, which does exactly what I want. From the manpage:



So a simple loop accros those files:



and the work is done. Simple. Powerful. I love it.