2" SCT focuser

[Louwai]

Hello all, Can any one help???? :help: I would like advice on what would be the best 2" focuser for my C8. I currently have a WO focuser which I haven't been happy with since new & over the weekend have found it to be miss-aligned which is creating issues with my colomation.
Can anyone recomend a quality focuser. I'd also be interested in an electric drive focuser.

I've been searching but can't find too many choices. I guess I'm looking in the wrong places.

Cheers, B

[gbeal]

Hi Louwai,
welcome aboard.
I am biased for sure, but THE best as far as I am concerned is the Feather Touch.
I happen to have one for sale (shameless plug!!), but at the moment don't have the correct adapter to fit it to your C8. They also make a motorized unit, this interfaces with a PC, and given the right software gives auto-focus.
Gary

[Bassnut]

I use the TCF-S from Optec, its motorised and temperature compensating (tracks focus change in the OTA as it expands/contacts with temperature). It has a contol box for manual control and operates with all astro software with autofocus. Autofocus is dream, no knocking the scope whilst fiddling with knobs, and faster and way more accurate than manual. Not cheap tho at US$800. Thing is, once you have a good one, focus becomes a no brainer and itll do several upgrades.

http://www.optecinc.com/optec_015.htm

Robofocus is another popular make.

Fred

[KG8]

How did you determine it was misaligned Louwai?

[Louwai]

KG8, First I must say that I'm not an Astromony fanatic. I love getting out there & looking & searching for objects, & I like to have good gear, but when it comes to the technical stuff I'm greatful when someone else does it for me. In addition, when I buy something of reputation I expect it to be good.

Last weekend a very generous club member at the MPAS slapped a colomation laser into it. (I didn't have the visual back with me to put the laser directly into the OTA). Colomated perfectly until the focuser was "spun" on it's axis. Was then WAY out. After investigation it seemed that the inner focus tube was actually not perfectly aligned with the outer body. Therefore creating a misalignment.

[Louwai]

Fred, Gary,
Thanks for the info. They both look good. I think one of those 2 will be finding it's way onto the back of my scope pretty soon.

Cheers, Bryan

[KG8]

thanks for the reply Louwai, I might get mine checked out.

[Louwai]

KG8 & others who may be interested. I contacted WO about my focuser & arranged with them to have a dealer here in Melb look at it.
I haven't picked it up yet, but on the ph he tells me that "it's fine, just needed some adjustment". When I dropped it off to him, it was a bit sloppy & the manual knob would not move the drawtube. This made the dealer a little wide-eyed as he was heavily pushing WO products to me as being the best in the world.
I'm just waiting to get it home now & try to colomate through it again. I'm interested to see if the "adjustment" has fixed the original alignment issue.

Cheers, Bryan

[Omaroo]

Absolutely no complaints about my WO SCT focuser by the way.

Out of alignment enough to affect collimation???? Can I ask by how much - I mean, if you were to aim the laser's output on to a piece of paper a foot away did the beam wander by a couple of mm or 6 inches? Sloppy I can believe - mine gets that way sometimes after a lot of twiddling, but it's a dawdle to adjust back up quickly.

Cheers
Chris

[Louwai]

Hi there Chris, Before the focuser went to the dealer I colimated the bare OTA. I then fitted the focuser to it & put the laser into the draw tube of the focuser. The laser didn't even appear on the target. Holding the focuser nice & solid, (with the draw tube fully retracted) I rotated it on it's axis. The laser appeared on the target, moved through an ark across it & then disapeared again. I haven't done the paper trick, but will try that when I pick it up later in the week.

Bryan

[Omaroo]

Hey there Bryan

Are you absolutely sure that the laser, itself, is collimated? They are notorious for not being so.

Cheers
Chris

[Louwai]

Chris, The process I outlined below was done several times using 2 different lasers. 1 of these I could say possibly may be not aligned as I bought it brand new & have done nothing to it. The other was a well used laser belonging to a well respected member of the MPAS, who did the colomation himself. Both lasers returned the same result.

I can only assume it was the focuser at fault.

Bryan

[Louwai]

Hello all who may be interested.
Well I retreived my WO focuser from the WO dealer. The whole unit is tigher, which I would expect as he tightened all of the body screws etc. (which I could have done myself). When I got home I colomated the tube putting the laser directly into the OTA & got it as close as possible. Then I fitted the focuser & put the same laser into it. The return beam was not even showing on the target. I looked down the OTA from the front & could see the return beam spot on the side of the mirror tube. I adjusted the colomation so the return beam was central on the target through the focuser, & then I spun the focuser on it's axis. Guess what, the return beam arked off the target & away of the side somewhere.
Unless I'm missing something, I'm pretty sure the focuser is missaligned.
I've ordered a Feather Touch. Can't wait for it to arrive so I can get rid of this WO. Credit where credit is due, I have a WO UWAN EP, Barlow & diagonal which I can't fault.
Cheers, Bryan

[Louwai]

Good evening all.
Well my SCT FeatherTouch focuser arrived. Of course I couldn't wait to get it happening.
It's on & working. My first reaction - AMAZING!! Feels fantastic.
The WO focuser doesn't even come close to this piece of precise engineering.
Collimation is an absolute dream. With the tube fully extended, & 1.5kg EP etc attached, there is not the slightest bit of movement or slop.

As I said previously, I have WO Diagonal, Barlow & EP's. They are great, but the WO focuser. I will never go near, or recomend one again.

FOR SALE - WO 2" Focuser. In original box. Serviced by WO dealer. Hardly used. As bought condition. :whistle:

[gbeal]

Glad you are happy with it, they really are good, as any new owner will attest. Enjoy.