Friday 2010-11-19 Dev. update and Discussion

[Sutts]

Originally Posted by choctaw111

The spiral effect of the smoke was not a camera shake issue. The spiral like vortices were actually present.
I had a 20mm MG-FF cannon shell pulled from a shot up B17. The hole for the tracer was off center. This is another contributing factor to the spirals.
The only thing about the wiggling tracers that I have an argument about is quite simple.
When viewing a tracer that is fired, it will appear as a streak traveling in a straight line, no wiggles, BUT if you are firing a handheld or semi fixed machine gun, the vibrations and recoil on your face will cause the tracer to appear a little distorted, very much like the camera shake.

Agreed, there's no way that the spiral effect we see in film could be caused by camera shake...if it was then the spiral smoke effect produced earlier in the flight of the shell would not be there in the subsequent frames..but it is.

I don't believe all tracers produced this spiral but some of the larger calibre ones definitely did. How it was produced I have no idea. We've seen balistic studies on this forum recently showing that bullets/shells do gyrate around an axis in flight but I can't believe this wobble was very large. Perhaps it becomes larger as the flight time increases and energy is lost?