how to change the frame rate once created the project

Having used i movie beforehand for my stop motions i was able to change the speed of the frame on each one thus I was able to make some frames longer and some shorter. I usually import my pictures and then put the music and afterwards i try and get the timing rights and change the frame per second but i find myself not able to do this with i stop motion because as soon as i open it, it asks me the frame per second and i have tried but have not found a way to change the time on various different frames how can i do this does anybody know??
please i really do not understand how you can make a proper stop motion without being able to change the frames speed sometimes at the beginning i need a longer frame and start the pictures flowing once the music starts the beat etc… please help
Thank you very much

Sorry, currently iStopMotion can’t change the frame rate. Please consider the following workflow:

  1. Think about the frame rate you want to shoot your video in advance. It depends on what will be your output destination and the smoothness of your animation: If you are presenting your results on a NTSC TV then you will have to have 30 fps. But you won’t shoot 30 fps because its a hell of work. so you go with 15 fps, or 10 fps because those are nice divisors of 30. If you going below 8 fps you will notice that the animation isn’t smooth anymore.

  2. iStopMotion can import a soundtrack and show its wave form in the timeline. (click the menu “Movie > Sound Track > Load file…”) If you happened to have the sound ready before animating this is the right way to animate to a sound! Clicking on the wave form in the timeline will playback the sound only from that point, so you can easily check what sound your are about to animate to.

  3. If you notice that your animation is to fast, you can duplicate single frames here and there to stretch out the animation time. (But this shouldn’t be happening if you are working with step 2)