Screen Captures with True Lasso effect

I’ve been looking all over the internet to find a simple way to capture screen shots with true lasso capabilities, not just one that captures in a square or rectangular fashion. I need to capture and save a partial image that can’t be done with a rectangular capture. I know some graphic programs has a lasso option but can’t figure out whether my Mac can do it with what’s built into it or if there’s a simple (and preferably free or cheap) app that will allow me to encircle what I need to capture and save it to new image. Can anyone help on this?

I use Monosnap to do special captures and then to add various other items. It's free from the Mac App store so it will cost you nothing to give it a try. Not sure if it's exactly what you're looking for but since it's free.....

Welcome to Mac-Forums..

The screenshot ability built into OS X allows you to take a full screen capture or a small portion through a rectangle. It doesn't support arbitrary sizes..I don't believe I've come across any that do it..

You might have to use the rectangle or full-screen capture method and then use the lasso option in your graphic program to crop it the way you want it.

Not really a true lasso but there's https://evernote.com/skitch/ which can be/is integrated with Evernote.