I am working on a project using After Effects where my client has given me different clips which appear to have different frame rates. For example their GoPro sequences are 59.54 fps, whereas other clips have been received with 23.976 or 25 fps.
Perhaps this is the first time I am confronted by a situation like this so asking you guys being experts as to what should be the right way of handling footage like this with varying fps associated to different clips. Normally, I prefer to search the forum before adding a new post, but it seems I could not find something more peculiar to my query.
For example if I want to have a consistent output of 23.976 fps and therefore keep 23.976 fps in my main composition, how it might affect my final result? Is there something I should do by forcing the fps in interpret footage options?
Your comp settings will determine the settings of your final output. Interpreting footage at different frame rates will change its speed.
Any footage with a frame rate different than the comp's frame rate will need to be re-sampled at the frame rate of the comp. The question is, how? If you have 59.94 frames in 1 second, how do you make that 23.976 frames per second? Some frames may need to be skipped, some may need to be repeated, and some new intermediate frames may need to be synthesized. You can control how layers with different frame rates than the comp are re-sampled by changing their frame blending settings.
Here is a relevant section from the documentation that will help you understand your options: