When you choose to record using Captivate, you choose a screen area. And when you play things back, you should be playing them back at the same size as the screen area you used when recording. Is this the case?
I'm guessing it is not, and that's the reason for loss of clarity. This often happens when you scale bitmap images to a smaller size.
Camtasia may do a better job of retaining clarity in this situation because TechSmith uses a propretary CODEC with their videos. So in this case, if full motion is your thing and you cannot or do not wish to adjust the workflow to present at the same size as recorded, Camtasia might be a better tool for you.
I think I'd be evaluating each tool, recording and comparing the results to see which gives me the best output I'm looking for.
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