I am going to make a lot of assumptions to give you the detailed overview. If I missed the target, please give more information.
What are you doing - a Timelapse video and wanting to know to what duration to set each Timeline photo in the series to order to have the Timelapse video with the total duration to give effect?
What is your project preset for the project - are you in a 25, 30, of 60 frames per second project? How many photos are involved?
I am ready to give you a generalized or customized reply depending on what you are wanting to do in your Premiere Elements project.
Please let me know if I have guessed right on your intent. If not, please give details since I suspect it is going to be easier for you if I do this by example.
Here is one example....You have 63 photos each imported into a 30 frames per second project and each having a duration of 5 seconds as set in preferences under Edit Menu/Preferences/General and the Still Image Default Duration = 150 frames (equivalent to 5 seconds). The total duration of that Timeline can be seen in the project as
00;05;15;00 (hours; minutes; seconds; frames; 5 minutes 15 seconds).
You cannot set for a still image duration less than 1 frame (0.0333 seconds).
So in this example
63 photos x how many seconds (duration for each) = total 2 seconds
2/63 would be 0.0317 seconds.
If we translated that into frames, the 0.0317 seconds would be equivalent to 30 frames per second x 0.0317 seconds = 0.951 frames.
Then, using Select All and Time Stretch, set the duration of the selected 63 photos to 1 frame (00;00;00;01).
To avoid the calculations, you might consider looking at the results from applying 1, 2, 3, 4, or 5 second duration to each of the photos on the Timeline and determine which gives the Timelapse look that you want.
After all that is said and written, if that does not apply to what you are asking, we will rewrite based on the details in your reply.
I'm working with a series of photographs that I need to create a slideshow-effect with. I am not doing a timelapse. I have a specific duration of time I need to evenly distribute the clips within. Let's say I have 10 clips that need to be distributed evenly from 3:30;25 to 5:20;15. I am working in 30fps. How would I determine how to distribute evenly?
Please check out these calculations and see if they work for you. I road tested them, and they seem to meet your requirements.
You want your 10 photos to be evenly distributed on the Timeline between the marking of
00;03;30;25 (3 minutes 30 seconds 25 frames) and 00;05;20;15 (5 minutes 20 seconds 15 frames)
Determine the total space (in time to be filled).....convert everything to seconds....
The first point is at 3 minutes 30 seconds 25 frames (equivalent to 210.833 seconds)
(3 minutes = 3 x 60 = 180 seconds; 30 seconds is 30 seconds; 25 frames is 25/30 = 0.833 seconds
Total Seconds = 180 + 30 + 0.833 seconds = 210.833 seconds)
The second point is at 5 minutes 20 seconds 15 frames (equivalent to 320.5 seconds)
(5 minutes = 5 x 60 = 300 seconds, 20 seconds is 20 seconds; 15 frames is 15/30 = 0.5 seconds)
Total Seconds = 300 + 20 + 0.5 seconds = 320.5 seconds
Total Space (in time to be filled) = 320.5 seconds - 210.833 seconds = 109.667 seconds
For 10 photos to fit that 109.667 seconds space, each photo needs a duration of 11 seconds (109.667/10).
Please review and consider and then let me know if that worked for you. If not, please indicate any problem areas.