Shift report

I thought more forum members would have wanted to do this, but I realise now that no Celestron or Meade owner wants to admit to what their image shift during focusing really is. So I have collected my own statistics on a few scopes and thought I had better report them. (These all happen to be Celestrons this time.)

My procedure was to look at high power at an antenna several miles away during daylight. The width of the antenna is about 45 arc seconds. (If I can ever find the reticle eyepiece that is around here I can get a better width measurment.) Suggestions for improvements are welcome. Here are my results:

Celestron (8" Orange tube on pier) Very close to 45 second shift. But very smooth, repeatable focus. Maybe collimation was better on this scope, or the pier added extra stability, but it seemed to "snap" into focus the easiest.

Celestron (8" Orange tube on tripod) Approximately 15 second shift. (Much harder to measure on tripod. Maybe I can repeat on a pier?)

Celestron (5" Orange tube) Approximately 5 seconds. This is getting down to the level where you might want to say "zero shift", but I would rather report anything as "less than X" where X is just the smallest angle I could reliably measure.

Celestron (5" Nextar new) Less than 5 seconds. This looks like the best, but I thought there was a peculiar "spring" in the focus that caused it to deflect ~10-15 seconds before snapping backto where it was. This went in both directions. This was the hardest to measure, because that tripod that came with the Nextar is next to worthless at over 200x. In either case, I much preferred the "action" on the older focuser.

SCT owners - please post more results.

Thanks,
Charlie