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Lee
21-09-2006, 08:56 PM
Hi all

Has anyone invested in one of these yet - Andrews and Bintel are selling them around $150 or so.
I really would love to know the dimensions of one if someone can whip out a ruler - mainly the distance from the OTA tube to the top of the 2" tube fully racked in - trying to get this darn DSLR into prime focus again! Hairpulling stuff.....
Also - what are they like in general - build quality, fineness of focus.....

thanks for any help....

spudrick
21-09-2006, 09:13 PM
Hello Lee
I got one of these a short time ago to replace a R&P. The build quailty is very good and they certainly seem value for money I paid $109.00 Andrews.
The height from the tube to the top of the 2" racked in is 78mm.
Have not used it yet in observing so i am sure others can tell you more details

janoskiss
21-09-2006, 09:19 PM
Lee, the distance from OTA to rim of 2" barrel is 3 inches within better than 1/16th of an inch (or 76mm +/- 1.5mm).

The focuser sells for little over $100 from Bintel or Andrews (I'm sure either will match price of the other - sticking to one dealer for your astro purchases as much as possible is a good idea), which is an absolute bargain. The fine control is fine indeed, very nice!, and even in bad seeing you can find best focus fairly precisely by defocussing in and out and then splitting the difference.

No backlash or image shift, big improvement over the standard GSO Crayford, which itself is a big improvement over the R&P unit. It is still not "feather touch" if such a thing exists and is not just a marketing term. What I mean is that if you have heavy EPs/barlows/camera/binoviewer in the focuser, you need tension adjusted up, and it will take enough torque to turn the fine focuser to make the scope shake a little. Hope I'm making sense.

Striker
21-09-2006, 09:22 PM
I just put one of those GSO Crayford with 10:1 microfocuser for $109 on my 8" Meade Schmit newt....great value for the money.

EzyStyles
21-09-2006, 09:22 PM
for $109 you can't go wrong with such a fine built focuser. it certainly worth every cent for me. It might not be a moonlight, but the price is a bargain for it. grab one :)
in regards to focusing issue, i can't comment on that as i had difficulties with mine using my DSLR. not enough in-focus. I made my own prime focus adapter. just use an ordinary 2" barrel and attach it to the t-mount.

Lee
21-09-2006, 09:27 PM
Cool - won't help DSLR focus though :( ..... the standard focuser is 72mm high....
Sounds like a good investment though - thanks for the replies! Adds to $hopping li$t.....

gbeal
22-09-2006, 05:55 AM
Hi Lee, there have been a few threads like this a while back, the in focus side anyway.
I got around these issues by having the primary fully forward (towards the secondary) on the collimation screws (got longer ones). I also opted for a lower focuser. Lastly, I got the T ring (mine was a Nikon)turned to match the 2" barrel that it fitted to, thereby allowing the lens throat on the camera to fit flush against the focuser. Every little bit helps.