This tool will adjust the capture dates and/or times of the selected group of photos.  The capture date/time is the time stamp written by the camera, usually stored in the Exif data of a photo

Often times the clock in a camera may be off, sometimes by a little, and sometimes by a lot.  The most common example is when you change time zones and forget to change the clock on the camera.  The capture times recorded are therefore still relative to the original time zone (e.g. before you went on vacation).

For multiple camera environments such as sporting events, it is often critical to synchronize all the cameras down to the second if photos from multiple cameras are to be viewed together.

This tool can be used to either "Adjust Relative" or "Adjust Absolute".

If you know your camera clock was off by some amount of time (e.g. 3 hours since you changed 3 time zones, or a camera clock that is behind or ahead 20 minutes), simply dial in the amount of time (or even days) in the Adjust Relative section.  For example, if you live in Boston and you went to vacation or work in San Diego without adjusting your camera clock, then set the Hours control to -3 to adjust the capture times of the photos from the Eastern to the Pacific time zone.

Another example: if after photographing with an assistant you realize that your assistant’s camera clock is 20 minutes faster than your camera’s clock, you need to subtract 20 minutes from your assistant’s photos using -20 minutes to align their capture times with your camera’s capture times.

To precisely adjust the capture times, use the Adjust Absolute controls to set the absolute time a photo was taken.  For example, with multiple cameras at a sporting event, make sure all cameras take a photo of the game clock (or some other common clock that shows seconds).  Then select the photos from one camera, locate the photo of the clock using the arrow buttons under the photo, then using the Time: input box to the right of the photo to match the time displayed in the photo of the clock.  A relative time will be calculated from that photo and applied to all the selected photos.

If the checkbox for “Use the adjusted time above for all selected photos” is turned on, then all photos in the selection will receive the exact same capture time. For example, every selected photo’s capture time will be 5:00:00 PM if 5:00:00 PM is set in the “Time:” input box above.

You can also choose to update the file system's creation by checking the box "Also update file system creation date/time".