Mavericks HDD swapped while in sleep mode is now unreadable Recently I was attempting to upgrade from mavericks to Yosemite and was having difficulty getting Yosemite to run.  I left the machine running rather than shutting down and it went into sleep mode. 
Several hours later I took out the Yosemite disk and replaced it with the one on which Mavericks was installed and hit the start button only to have the computer come to life immediately and started writing to the Mavericks HDD.  Needless to say I now have a corrupted Mavericks installation with about 500 gigabytes of images and video recordings which I cannot access.

Is there any way to recover files off this disk or should I just wipe it cut my losses.
Oh man - that's a bad situation. All is certainly not lost.

I would start by calling one or two data recovery services to get a quote from them. Once you have that, consider you could pay $99 for software that would look over the drive and offer to recover files.

With those estimates, you can decide if your time and photos are worth further efforts to salvage or if you just write them off and erase the drive to start over.