It drives me nuts that Grab.app defaults to .tif as the file type. And no matter how many times I try the recommended :
defaults write com.apple.screencapture type jpg
I can not get it to default to save as a jpg (and I tried jpeg). All I can guess is that this command does not work in 10.6. I don’t know. It drives me nuts.
So I sat down and created a quick OS X Service in Automator that takes files as an input and changes them to jpg. First in automator I selected “Service” as my workflow type
Next, I set the Service receives selected “files or folders” in “any application” values. Then I added the “Change Type of Images” action and set “To Type” to JPEG.
Hit save as “ChangeToJPEG” and now when I right click an annoying .tif, I have an option under Services to ChageToJPG
Grab.app is still annoying, but this makes it more tolerable.