Your video has really inspired me. One of the keys to problem solving is it to convert your impressions to numbers. You've just invented the "Duffy prop analysis method".

 

Measure the distance from you hangar door to your prop. Put mark on pavement, say at 20 ft. Put another mark at 30 ft. That's where your camera goes. Now, video your engine as well as others at those same locations. Calibrate your system by measuring the distance between the pleats on your hangar door.

 

Now go home, sit on the couch, get a beer. Fire up your videos. Find the worst deflection by using slow motion. Measure how far prop tip is from the hangar door pleat in background. So it's going to be around 1/4" on your video screen. We can convert that mathematically to actual tip deflection at prop! You've now measured deflection of 4 different aircraft and haven't lost a finger.

 

Then you just test your various ideas, trying to beat the best measurements you could find.

 

You could also use the video to measure prop diameter. Just in case one of the planes has different diameter. That would also prove how accurate this method is. I expect it would be unexpectedly accurate and meaningful.

 

Write up your test. This would be great one for Contact.

 

-al wick
 

If you want to use an off-the-shelf method, there is a company that makes software that will measure anything if a reference square is in the picture.  See http://www.iphotomeasure.com/index.asp

 

Have not used it myself, but it looked interesting.

 

Grant Schemmel