TOPIC:

Hi - I hope I'm asking this in a way that it makes sense.

I have 2 clips of different lengths that I want to zoom in at the same constant speed. I don't need them to zoom in the same amount.

Is there an online calculator or an easy way to do this? I couldn't find anything and calculated it via a simple ratio shown in my example below.

The first clip is 6 seconds and 14 frames (158 total frames) and zooms in 50% from 100% to 150%. The second clip is 6 seconds and 0 frames (144 total frames) - on a 24FPS timeline.

I divided the second clip into the first to get a ratio of their length and then multiplied the zoom of the first clip by that ratio, which gives the amount of zoom the second clip should use.

So:
144 frames/158 frames = .911 ratio
50 percent zoom * .911 ratio = 45.56 zoom for the second clip - which I rounded up to 46 and then used 146% in FCP for the second clip

I'm not sure if others do this, but I like it when my zooms are all a constant speed. Any insight on how to calculate it easier would be great. Thanks!

The easiest thing to do is to create the zoom effect on one clip. Then Copy the selected clip. Select a second clip (or multiple other clips at once), then Option-Shift-V (Paste Attributes). Make sure that Keyframe Timing is set to Maintain. I would recommend setting the keyframes on the shortest clip of your set and applying to the longer clips after.

Thanks so much for the reply. I need thought of doing that, but it will definitely make things easier. One issue I found - if I take the shortest clip's attributes and paste them to a longer clip with maintain set, the zoom stops at the same time as the short clip and doesn't keep zooming for the rest of the long clip. If I choose stretch, it zooms all the way to the end of the longer clip, but it zooms as a much slower speed. I found that copying the attributes from the longest clip and pasting them into the shortest clip with maintain checked works perfectly. Not sure if I'm doing something wrong with copying from short to long, but it's working perfectly going long to short, and I really appreciate your suggestion. Thanks again!