I've noticed the small movies I take on my iPhone 4 result in large .mov files. For example, a 1 minute movie results in almost a 100MB .mov file. This is running through my cloud storage (Dropbox) rather quickly. Is there an easy way to reduce the quality/size after transferring to my Mac?
Most of this is documented:
The Finder has built in video encoding and you could even use these to set up watch folders and attach a pre-set conversion using Automator if you found one setting that you prefer...
You can transcode them while transferring!
You can do exactly same automator workflow but make it an Image Capture plug-in. So you can choose in "Image Capture" videos from your iOS device and import them transcoded.
Really easy steps are presented on macworld.com, basically you use
and import your movies using Image Capture.
If you check the box [Show this action when the workflow runs] you will be able to choose destination folder and compress options.