Upon the recommendation of a fellow mechanic I bought this borescope from Oasis Scientific, the VA400 Ablescope with 180 degree Articulating head.  That is, when you push the button on the handle, it rotates the head so you look backwards.  This is so much better than the mirror you have to clip on some of the other scopes.  Also the resolution of the camera is very nice, definitely not the 320 by 240 we see in the wireless versions. At $149.98 (shipping included) it beat the 159.99 (plus 18.63 shipping) I bought 2 years ago from Sam’s Club.

http://www.oasisscientific.com/vividia-va-400-rigid-usb-articulating-borescope-videoscope-inspection-camera.html
So here is the scope hooked to my Samsung Galaxy III (android) which it worked with after I choose a free USB camera app (I choose the one with the smallest footprint).  It also worked with my macbook and my iMac 27 out of the box with PhotoBooth as an external camera.

With the phone I can take pictures and video and email them to myself.

Here is the view at 3 inches showing resolution

Here is the view at 3 feet so things are a bit blurry.
Tomorrow at the shop I will take some pictures in a real cylinder and post them here. I will try and get the cylinder from the overheated valve.

Here are some shots from real cylinders, a good one, and the bad one with the red exhaust valve (bad). This first cylinder is a 900-hour Superior Millennium that was removed due to exhaust valve guide wear just within limits. The cylinder is from a Grumman Tiger so it is from the O-360 engine.

That was the good cylinder, here comes the bad one. This exhaust valve has had some heat go through it.

Notice the intake is nice in color.

Here is a shot of both valves in the cylinder for the O-320 Cheetah.

The plan is that every plane that comes through for engine work/annual/prepurchase will get a digital copy of the internal cylinder pictures added to the maintenance file.

Cheers

Roscoe
Yankee-Aviation.com
513-519-7008