Default date field values like "today +10 hours 30 minutes" I have a date_field Date (ISO format) as a Pop-up calendar. I would like to have it as a default value: today 10:30
In php the

strtotime("today +10 hours 30 minutes")


serves me well. Also

strtotime("today 10:30 am")


If I put it in the "Relative default value" field, the time gets not parsed. It is always the current time.

strtotime("noon")


or

strtotime("midnight")

has the same effect. Bug? How to get the default date to "today 10:30 am"?
The best way to control the default output of form elements is through the drupal Form API.

You have two scenarios:


If you created the form with the form api and have a date popup in your form, you can use the method described in this post to set the #default_format of the #default_value of the form element.
If you didn't create the date popup in the form element with the form api, meaning you added it as a field to an entity through site configuration, you can still make a small custom module solution.  Make a custom module and implement hook_form_alter, find the field in question and set the #default_value using the method mentioned in #1