Crayford on LX200 Classic - How much of a pain is it?

I'm currently exploring my options for providing fine focussing on a tight budget for my 8" LX200 Classic. At the moment I'm leaning towards buying a JMI Motofocus to attach to the main focussing knob in conjunction with a Peterson EZ focus conversion kit and FocusMax autofocussing software when imaging. Whilst this set up should reduce image shift, it will not be eliminated and may stay problematic.

The obvious answer is a Crayford focusser mounted on the rear cell of the LX200, but this will cause problems as I will not have enough clearance to use the scope near the pole (about 15-20 degrees radius around Polaris). My perception is that this would be a major pain in the neck; but is this perception correct?

So, calling all you who have a Crayford mounted on an 8" LX200 Classic (or similar); what do you think?

The JMI focussers are very nice, but as you say, you may end up with problems pointing near the pole as they are between 45mm - 90mm fully racked in and fully racked out. Another option (designed specifically for SCTs) is the Clements' Focuser. This is only 1" high and can be screwed directly onto the back of an SCT. Check it out at:

www.clementfocuser.com/pages/1/index.htm

Hope this helps, and Happy New Year,

Phil.

Hi Michael,
I also have a classic lx200 and went for a 2" helical borg focuser, it has millimetre increments which has proved useful on occasions. What I like about this helical focuser is that you can make very small focusing adjustments easily with no chance of image shift or slip with a sizeable amount of weight hanging off it.
This is a manual solution and is not motorisable.

The clements focuser have a good reputation if you want to go that way.

Philip
The Clements focusser looks very nice but I'm after a low budget solution. The Clements unit starts at about $600!

Dave
What model Borg helical focusser do you use? I'm assumimg your LX200 is fork mounted. Do you have issues with clearance? If yes, how do you overcome them and how much of a pain is it?

Philip
The Clements focusser looks very nice but I'm after a low budget solution. The Clements unit starts at about $600!

Yeah, a bit steep alright - I had forgotten they were so pricey!

Phil.

Michael,
I might have lead you down the wrong path here, my scope is the 12" so I never have any clearance, I doubt if you would either with the 8".
My scope is on the superwedge, so I get in the zenith, although the pole can be a problem.
FWIW, the focuser is the Borg 7835
www.borg-telescopes.co.uk/shop/focusers0001.html
have a look at the bottom of the page,

I think a 1.25 inch focuser would suit you better, maybe a solution for you is to use the 1.25 diagonal directly onto the back of the scope and then have the 1.25 helical focuser plug into the diagonal.
Have a look at this review, this guy put one of these focuser's on his etx105, although he didn't use the diagonal the way I mentioned.
www.weasner.com/etx/reviews/2006/borg-focuser.html

Have a look around astromart.com for these second hand, its alot cheaper that way.