Temp Fix on Overheating
Well, I'm frustrated that Sony has not fixed this overheating issue, I have found somewhat of a fix. It seems that the issue is not so much the overheating but that it is the firmware and the Electronic circuit, or heat measuring device is not accurate, and trips the camera cool down screen.
I have found a temp fix that was listed on another video forum: It seems to work, Yesterday I could not get a video to record for longer than 4 minutes, turn it off wait awhile, restart, then my be 2 minutes, tried the method of taking the battery out and reinserting it seems to reset the camera, and aloud me to shoot multiple clips ant longer than 4 minutes. COME ON SONY, LETS GET THIS FIXED in Firmeware SOON!!
Here is a copy of what I found"
I just talked to Sony about my NEX-7 yesterday and they admitted a few things to me which align with my tests and with yours.
All Sony alpha cameras have additional undocumented features for protecting against heat well beyond straight thermal limits.
These include how often and how long recording takes place. If you record too many clips, too quickly back to back, for too long, the camera will shut down with the 'cool camera' warning even if the camera isn't hot or showing the temperature warning icon on the screen.
Pulling the battery out between recordings resets these timers/counters and eliminates many of the overheating issues...as they are not temperature driven but timer/counter driven. Sony of course warned me that I could damage the sensor by doing this but then they have to stand by the design of their product.
They admitted that this could be changed in firmware down the road but with the new A77 firmware coming out today with no change to these sorts of features, and the 5N firmware just having come out and not really changing anything, I doubt we'll see anything soon which helps the NEX cameras.