Fine focuser wanted

[[1ponders]]

Does any one know if these or similar are available in Australia. I'd really like to get rid of the standar cheese grater on my Celestron Refractor

[ving]

have you considered motorising your current one?

[ballaratdragons]

Eek! Yuk!! A Rack & Pinion.

Get rid of the Rack & Pinion all together and get a Crayford. Mucho Betterer.

[[1ponders]]

Ok Ken, I'm open to suggestions. Everyone raves about the Crayfords for the newts. What are they like for refractors if available? Though after having the fine focus on my meade I'm rather smitten with them. Hence the "want" for one for my refractor. Plus the important bit, I like the look of it. Always important:P

Ving, any idea where I can get a motorized one to fit my refractor? Any recommendations?

[ballaratdragons]

Sorry Paul, I don't know where to get a Crayford for a refractor. I have only heard of them coming standard with the scope, not as an accessory. Maybe someone else may know where to get them.

A Crayford is soooooo smooth. Fine focus is easily obtained.

[Vermin]

If you want the best and are prepared to pay for it, have a look at the "feathertouch":

http://www.starlightinstruments.com/schmidtCassFocusers8and15.htm

I can't believe how smooth and repeatable (zero backlash) it is, even compared to the Moonlight dual rate focuser - which is also an exceptional device, but not made for SCTs AFAIK.

[[1ponders]]

Thanks Vermin, I can dream about it i suppose:) Though I think even with a 3" travel focuser I don't think it would have enough travel to use it for both Photography and visual on the same scope. When I'm doing positive eyepiece projection with my 300D I need nearly all the travel i can get, at least 4"-5".

I quickly checked out the Moonlight focusers and hurriedly left the page and checked my credit card wasn't too handy. Very nice.

[Dennis]

Hi Paul

I have a JMI NGFS motofocus crayford (no tools) focuser which fits the 2" fitting on my Vixen 4" refractor. This has become an essential accessory when I use my Meade LPI or ST7 ccd camera. The focus travel is approx 1/2 inch so all I do is rough focus using the rack and pinion then fine focus with the JMI. It cost me an arm and a leg, 'cos I bought it from the US when the Aussie $ was worth peanuts, but it was worth it. The Vixen 4" and the Celestron 4" may have the same fitting, so it might be worth exploring this option?

Let me know if you want any further details. Current JMI price is $139 US.

Cheers

Dennis

url for JMI is http://www.jimsmobile.com/

[[1ponders]]

Hi Dennis. Let me clarify a bit here,. Are you saying that the JMI fits inside the existing focus tube, so you have in fact two focus option on the OTA? I hope that makes sense.

[Dennis]

Hi Paul

Aghhh - forget it. I've just been to the JMI website to find a picture to help explain how it fits and works, only to discover that the JMI NGFS has now been discontinued and replaced by the NGF-C and NGF-CM - bugger!!

Sorry for the false lead

Cheers

Dennis

[[1ponders]]

Just checked it out Dennis, thanks.

Keep 'em coming guys. Once I've got a list I'll ask for impressions/comparisons etc

BTW check out these little beauties
http://www.observatory.org/featurmc.htm
Then check out the prices :P
http://www.observatory.org/scfmacro.htm
If you've not been to this site before, have a good look over it. I guarantee you will be drooling and rubbing your hands together with lust.

[ballaratdragons]

Drool, Drool, but those prices. OUCH!! None of them are cheaper than my 12" Dobbie.

[[1ponders]]

I know:eyepop: but aren't they luvly:love:. You never know :xmas: is coming :rofl: :rofl: :rofl:

[ballaratdragons]

All that amazing technology and John Dobson STILL! makes and uses Brass Drain pipe and cardboard tube 'Slide' focusers.

I gave up on my PVC slider yonks ago.

[[1ponders]]

Ahh but I have been seriously bitten by the astrophotography bug Ken. John still has his sanity :D

[Dennis]

John Dobson and his Son stayed at our house in Brisbane overnight, on their way to the Queensland Astrofest in 1995. I was quite new to astronomy then and was not aware of his fame within the astronomical community. He is a very interesting man and heaped scorn on a book I had titled "Amateur Telescope Making" by N.E. Howard, saying it was too complicated.

He breakfasted the next morning on some Nasturtium flowers and leaves in the creek behind our house, although his son had a more traditional breakfast. Due to work commitments I was unable to attend that astrofest!

Cheers

Dennis

[Exfso]

Just for info, Bintel are the Aust distributors of JMI focusers. I have a motorised JMI on my Schmidt Newt and it is excellent.
It might be worth contacting them and seeing what would be involved to add a JMI to your scope.

[Exfso]

Here are a couple of shots of the JMI on my SN10

[Exfso]

Another

[ballaratdragons]

Haha! you only put that photo of your focuser in to show off your Nagler!!! LOL

[gbeal]

Paul,
with having yet ventured towards the Feathertouch, I have tried a few of the better ones. I have a delightful helical focuser on the 80mm refractor, but lately I have been using a JMI NGF-S, with the Smart Focus. The Samrt side of it isn't getting too much use, well not yet, but the motorised side is. I am able to fit it to all my scopes, via the 2" focuser. I will show you this weekend.
Gary

[iceman]

Moonlite do make CR2's for SCT's. They're a wonderful focuser. They can do integrated filterwheels as well, and i'm pretty sure there's a motorised version.

[ving]

if you want to motorise cheap you can make one yourself... rajah makes them so you could ask him maybe. :)

[[1ponders]]

Thanks for all your responses guys. I've checked out the Moonlite, the JMIs the FineFocuser2 , the Feathertouch, and the awesome site at Van Slyke Engineering (goes straight to the heart of any gadget geek and if I ever win lotto then you'll see some swish custom built astronomy accessories). I've wittled it down to the first three at the moment. The moonlite lookes great, the JMI model NGF-CM for my refractor would allow me to switch it between an SCT and the refractor, and the FineFocuser2 looks like the most affordable yet achieve what I want. I'd love to get the Moonlite but the focuser would cost nearly as much as the scope. The JMI is definately an option, maybe without the motor to start with.

I've got time to think about it. After my trip to NZ this weekend there won't be too many purchases for a while unless Mr Taxman is very kind to me after June. :P

If its there I'd love to have a look at the JMI Gary, though checking at the JMI site that model is discontinued and is replaced by the NGF-CM (with Smart Focus as extra of course)

[ausastronomer]

Paul,

Williams Optics make a 2" aftermarket replacement crayford focuser for refractors. It is the same focuser as fitted to all of their refractors and is a really good focuser. WO focusers are IMO superior to JMI manual focusers. Haven't tried the motorised ones but I find the fit and finish and smoothness on JMI manual focusers to be a little inconsistent compared to the top level stuff, from Feathertouch, Moonlite and Williams Optics, which I rate in that order BTW. The machining tolerances on JMI stuff just doesn't seem as good as the rest IMO. I haver also used a few JMI focusers that had quite a "notchy" feeling to them.

http://www.frontieroptics.com/ATM%20Parts.html

www.atscope.com.au

The WO focusers are reasonably priced for the quality of focuser you are getting, considering its better and probably cheaper than the JMI.

CS John B