Ordering photos on an iPad

When photos are sync'd from iTunes to an iPad, the order they appear in on the iPad is not filename order. The apple support website says that the photos are sorted by various date tags in the EXIF metadata stored in the JPEG, most notably the EXIF tag "DateTimeOriginal". I think this tag is also known as "Capture date", but for sure it shows up in Windows 7 Explorer as "Date taken". None of my photos had this tag set (the field shows empty in Explorer).

I googled various posts on this issue, some of which indicate that clearing the EXIF metadata completely before sync'ing makes the photos sort by filename when they get to the iPad ... however this did not work for me.

My first attempt was to write a Java program to set DateTimeOriginal using the Apache sanselan library for reading and writing image metadata. Although my program seemed to work, and the "Date taken" was showing in Explorer, after sync'ing the photos were still in the wrong order ... very vexing!

Whilst googling, I came across a utility called ExifTool (google for it), and its companion ExifToolGui. This program has a feature to set the EXIF DateTimeOriginal tag in a group of selected JEG files - i.e. the same thing as the program I wrote; however, after usng the tool and sync'ing the photos, it worked! The precise sequence of events is

* Run ExifToolGui
* Select all the photos you want to change
* From the menu, choose Modify and Exif Date/Time set and incremement ...
* Select DateTimeOriginal as the date, and enter the start and increment
* Click Execute
* When done, sync in iTunes

If you need to do this, I wish you good luck!