bargain GS Crayfords

[janoskiss]

Bintel have dropped their price on GS Crayfords to $99. I just ordered one from the Sydney shop. (Couldn't wait for Melbourne store to catch up, and risk not getting one before xmas break.)

Now you really have no excuse not to upgrade that old R&P.

:)

[ving]

want a full report on the gs cray steve. my r n' p is silky atm and i'd want a good reason to change it :P

congrats on your purchase btw :)

[janoskiss]

David, It is the same focuser that the Premium GS Dobs come with.
End report.
:D
Actually, there is a bit of variability in quality with these cheap units. I tried two at the Melbourne store. One on a 12" Dob: uneven tension (going from racked in to racked out needed readjusting); another new one out of a box: nice even tension but the gearless pinion shaft (you know what i mean) was not held snugly enough, so there was some backlash. In any case, it will be heaps better than my R&P which suffers badly from image shift even though it is very stiff. (It was quite decent till I killed it with a heavy SLR camera in an adapter in a barlow in a 1.25" adapter)

[Thiink]

Steve stop it! Between your For Sale threads and this one you are driving me nuts! If it wasnt xmas Id have your Orion EPs, the ED80 and a Crayford on my door this week!

.. though if the EPs are still for sale early next year it could make things interesting. :P

[Starkler]

Makes collimation so much easier when your focuser tube doesnt wobble :cool:

In mine I can hang a 31 nagler out of a long barlow with zero image shift.
If you dont have one, get one !

[ving]

what a nagler on a barlow?

[janoskiss]

It is precisely because of xmas that you should buy all those things and then some! Get yourself some presents people! :D

[ballaratdragons]

I've got a Crayford!

And love it :love:

[iceman]

They are a thousand times better than the R&P. Gazz (irish), you should take advantage of this price!

Gazz's R&P is about the worst i've ever used. It's simply horrible.

[matt]

Mike

I forgot to tell you my MoonLite CR2 arrived a few weeks ago.

What a beauty, and I love the dual rate focus. Smooth as!!!!

To those who recommended it as a replacement for my stock standard R&P... including you Mike, thanks :prey2:

They cost a bit ... but what a difference at the EP

[iceman]

oh yeh, definitely a worthwhile upgrade. The 8:1 ratio on the fine adjustment side is just perfect.

[Kieken]

I installed a Crayford today on my Starhooper. Looks so much cooler now :). Here's a pic (http://users.pandora.be/willy.geys3/Astronomie/Telescoop/Crayford/DSCF0419_800x600.jpg). It's the same one Bintel sales but mine has a little upgrade. Up to you to find out what.

[ving]

very coo looking kieken :) very cool

[Roger Davis]

It's the old "you get what you pay for" unless you know how to modify it properly.
You can pay $99 or $399, but which do you think will perform better?
AstroSystems has been making the Phase 3 and Phase 4 focusers for over 15 years, great focusers at reasonable cost. The Moonlite is a great focuser also, my mate has one on his 47cm f/3.9 and it's wonderfull! Not to mention the JMI range.
You can't expect to pay $99 and get $399 quality, otherwise the thing you're buying WOULD be $399.

[ausastronomer]

Mike,

There is no "about" involved here, Gaz's focuser wins the "worst ever" award quite comfortably :)

CS-John B

[janoskiss]

Well, I've fitted my Crayford to the Dob last night, and it's sweet. Bit of backlash with this one too, so it seems you'll get that with most of these units. But it's lightyears ahead of my R&P. Well worth the small investment. Handles big 2" barlow and nearly a kg of Stratus eyepiece without even breaking a sweat. The bit of backlash is only in the shaft and not the barrel, so there is no image shift.

The Crayford on the ED80 is a lot smoother with a much lighter touch and more sensitive tension adjustment. And when you get the tension right, there is no backlash. I thought that would have been a bottom end cheapie too... Maybe Synta make better focusers than GSO, or maybe refractor focusers are easier to make... :shrug:

But I don't think I'll be buying any $400 focusers anytime soon; not till I have a $4000 telescope to put it on anyway.

[Starkler]

If you are getting backlash in a crayford, it can only be the pinion shaft skidding on the main barrel flat, or the knob loose on the pinion.
Either case should be fixed with a bit more tension.

As for the ed80 focusers, they have their weaknesses. They often have a very light movement due to the barrel flat not being machined very well.
Because of this they cant hold much weight without sliding. Clamp down on the tension screw too much and you mangle some nylon bits inside.
There are fixes and mods for these issues though.

[janoskiss]

It's the pinion shaft being a bit loose in the bearings/bushings. If you grab both knobs and push one and pull the other, there is a bit of swivel in the shaft. If you press or pull on both knobs as you focus, the backlash disappears.

I must have got lucky with my ED80, I never had any problems (apart from getting used to adjusting the tension when changing EPs). It could handle 1.5-2kg worth of diagonal + barlow + eyepiece in it. Very smooth and even except at the very end of in-travel, which is rarely used anyway. (it is sold and paid for by the way, so I'm not making this up. :P)