On Jan 11, 10:35 am, "Larry L" wrote:

Using a trackball type "mouse" and being as careful as I can I get distinct
jumps and can not, ever, find a postion between those jumps.

What Sandy is proposing would still have jumps, although why stop at
40 pics if all you have to do is click a mouse? ;-)

If you look at some of the other flies, there are pretty big exposure
jumps between some successive images, as well as focusing changes.
That wouldn't happen with interpolation.

E.g, choose "Peter Koga", "Steelhead 1", and make the fly face
directly away from you. Then rotate it counter clockwise (as viewed
from above) and watch the next 4-5 images.

Jon.