I found a bug in the GPSTimeStamp setting for images from iPhone 3GS. The seconds column has a value up to four digits long, which was apparently supposed to be hundredth-seconds. ExifTool (v8.84) treats these as full seconds. In the printable output it carries the extra seconds over to the minutes column to get a valid timestamp. That is sensible, but in this case it can skew the timestamp up to a couple hours. In other words a raw timestamp like this:
GPSTimeStamp = 19 35 4135 (19/1 35/1 4135/1)
should have been:
GPSTimeStamp = 19 35 4135 (19/1 35/1 4135/100)
Images before about 2011/05/15 have timestamps with a decimal point in the right place. Apparently the bug was introduced to iPhone around that time. I put together a script to fix these images for anyone who is interested. It will update GPSTimeStamp, replacing the integer seconds with a real/floating-point value.
Nice script. Thanks for sharing. I wasn't aware of this bug in the iPhone GPS.
- Phil