An equipment question
Posted 22 December 2012 - 02:20 AM
Anyway from a variable star point of view, does anyone think such a rig would have value, or better to stay with the 8inch
Posted 22 December 2012 - 03:45 AM
Posted 22 December 2012 - 07:32 AM
Posted 24 December 2012 - 07:19 AM
Posted 24 December 2012 - 05:25 PM
My personal recommendation would be that if you truly wish to have an instrument that compliments your SE8 in your variable star observing program and you a really familiar with the sky, that you purchase a pair of larger (say 9x63, 15x63 or 15x70) binoculars and use these to cover the brighter stars.
Posted 26 December 2012 - 09:49 AM
IMO a 8" scope is ideal for visual VS work on stars in the approximate range mag. 11.0 - 13.0. (You should be able to see fainter stars than that but errors accumulate close to the threshold!) A 80mm short focus refractor for stars in the approximate range 9.0-11.0 would complement it nicely. But I'd query whether it's a good idea to have it on the same mount: a good but easily portable altaz mount will allow you to move to a different observing place, so you can access the bits of sky that are hidden from your usual spot, without having to go through the tedious alignment procedure again ... and the SE mount is IMO compromised by relying on the motor drive.
One practical aspect of this ... if your scopes have the same type of finder then it is easier to locate an object in the scope on a "dumb" (push to) mount by comparing the field shown in the finder on the scope equipped with goto.
Personally I use several instruments for VS work: naked eye, 4x20 binoculars (hand held), 10x50 binoculars (on a camera tripod), 80mm f/6 doublet refractor & 6" SCT tube (on a Skytee 2 altaz mount) and a CPC 1100. That gives me a complete working range with "optimal efficiency" from about mag. 2 to mag 14 with a faintest object threshold (on a transparent dark night) of around mag. 16.
Posted 26 December 2012 - 12:48 PM
I think the suggestion for a separate tripod makes good sense and I will ultimately go down that road. Many variable observers have suggested binoculars, but the times I have used binos I have never really enjoyed them....but who knows what the future may bring