Hi all,
It's simple and tricky at the same time.
As already said - the captured is the date when the photo was taken, and the added is the time it was added to the site.
The is one thing I have to mention that could cause confusion. The added timestamp is SERVER time internally. If you are logged in, and have your timezone set, corrections are sometimes (not always, depending on application) made to dates and times through the whole site, so that it's converted to your local time.
The added could hence differ if you're logged in, or not.
The timezone "correction" exists in multiple layers (hardware, database, web server software, web script software, end user software/js, site specific funtions). Due to the many levels of timezones available, at times there are errors that are really tricky to both find and fix.
You can always use the "Contact" page and submit a bug report, should you find anything particular strange behaviour concerning dates and times.
The date picker says "Date of photo". It should be the time when the photo was captured. The time it was added to the site we already know without asking for it. The "adding" date is also what we sort on when showing "New photos". New photos are new for the website, but could be photos taken 30 years ago. It's still new to the site, if it hasn't been shown here before.
Regards,
Henrik