New focuser for C11

[Carbon]

The best choice is the FT Crayford as it's very compact and much lighter than the Baader, but of course more expensive.

John

Photo of my old C11 with the FT crayford.

Hello John,

I'm in the market for the FT Crayford for my CPC1100 and was wondering about the short profile adapter with short draw tube focuser set up you had on your old C11. Did the short draw tube give you enough focus range without having to move the primary mirror when using different types of eyepieces?

According to Starlight Instruments the longer draw tube and adapter is the most popular set up for more versatility. I'm trying to decide which way to go.

Thanks!....George

[johninderby]

Hi George

At the time (the CPC 1100 had only just come out) they recommended the shorter travel one for clearance between a 2" diag and the base, but I think they've found out it's not really a problem.

The shorter one though never gave me any problems as I'd set the FT at half travel and then focus with the CPC focuser and then use the FT as the fine focus.

John

[Earl]

I have a 2" FT with the 1.5" Drawtube for my C11, to get focus I set this to half way, get close with the main primary focus the fine tune using the motorized FT

[Carbon]

Thank you John and Earl for your replies.

I contacted Starlight Instruments the other day and I inquired about using the 1.5" draw tube with the shorter adapter. They told me that the draw tube will "bottom out" and will not rack all the way in. I'm having a hard time visualizing this given the large diameter opening of the visual back......'bottom out' against what?

So according to them I must use the 0.8" draw tube with the short profile adapter. Switching between 1.25" & 2" I don't want to fiddle with the mirror focuser every time I switch eyepieces, if that is going to be the case.

Thanks again....George

[Dunkster]

I'd guess the baffle tube. While the vb has a 3.25" thread, the baffle tube itself is only 48-50mm.

[Carbon]

I'd guess the baffle tube. While the vb has a 3.25" thread, the baffle tube itself is only 48-50mm.

Ah, that makes perfect sense, thank you.

George

[AztecastroMcJ]

hi George

i havent owned cpc but have read clearance for viewing near zenith could be problem,

(personally its rare i view near zenith objects anyway)

maybe sum1 with cpc can let u know suitable focuser, i'd give flo or sum1 else phone as i'm sure there used to selling to other cpc users

hth James

[AztecastroMcJ]

I'd guess the baffle tube. While the vb has a 3.25" thread, the baffle tube itself is only 48-50mm.

haha u were close Dunkster, baffle for C11 is 54mm

p.s didnt realise u had C11

heres baffle sizes from celestron for range of scopes

http://www.celestron.com/c3/support3/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=2429

[Carbon]

Hi James,

Clearance near or at zenith is not a problem with the cpc1100 as there's 8" clearance between the mount and the visual back so most crayford focusers I've looked into getting work just fine with a 2" diagonal.

George

[Dunkster]

haha u were close Dunkster, baffle for C11 is 54mm

p.s didnt realise u had C11

Nice one - my rule must have been wonky

Re: C11... yeah I'm blamin it all on you :) (and the recent promotions LOL)

[Carbon]

I went ahead and placed an order for the 0.8" drawtube Feathertouch focuser and a matching short profile visual back adapter for my cpc1100. Thank you for the replies!

[Carbon]

I received my Feathertouch focuser yesterday and I'm very pleased with the set up. Thanks again.

[deepspacehunter]

I have the MOONLITE cs SCT FOCUSER and it is a joy to use !