Nate’s question is: “How do I change the capture time by any amount (as in NOT just by exact hours…but any # of minutes I need) on a bunch of images at once?”
First, make sure you are in Grid mode.
Select the first image in the series, and note the time that this image should be set to.
Select all of the images that need the timestamp changed, keeping the first image as the most selected (lighter gray).
Go to Metadata menu > Edit Capture Time… and this dialog will appear.
Choose the first option ‘Adjust to a specified date and time’ as this allows you to change by years, months, days, hours, minutes or seconds.
Now, in the Corrected Time section, adjust to the correct time for your FIRST image – the time you noted down earlier. You can select each timestamp section (hours, minutes etc) individually, and either use the arrows or type the time of your choice.
And then hit Change All. Whilst not entirely obvious, this will update all of the other selected images by the same time difference – it won’t set them all to the same date and time.
Exactly the same process can be used for matching up the timestamp when shooting with multiple cameras.
One point to note on changing times in Lightroom… this does not affect the original file. Any files which are exported do carry the new timestamp. The changes are stored in the catalog, and you can return to the original time stamp at any time by using Metadata menu > Revert Capture Time to Original.