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View Full Version here: : Recommendations for a Crayford focuser


toryglen-boy
16-03-2009, 02:51 PM
Howdy

Am looking for recommendations for a good quality Crayford focuser, preferably with additional fine focus, and any colour, as long as its black!! (or chrome) looking for something good, with no sag, low profile isnt a must, but must take 2" and 1.25" pieces, and just be generally alround well made, oh .. its for a 12" tube.

thanks

:thumbsup:

astronut
16-03-2009, 05:18 PM
Duncan,
I'm using the 10:1 fine focus Guan Sheng made Crayford,
http://www.andrewscom.com.au/images/products/telescopes/accessories/gs_focuser.jpg
Around a $120 it's a great piece of kit.
You can buy Crayford focusers from Moonlite in the U.S.A, but you're paying approx 3X the price.
I've found the G.S model to be smooth and works very well.
John:thumbsup:

Glenhuon
16-03-2009, 06:16 PM
I've got 2 scopes with the GSO 10:1 focuser fitted. The one on the 4" refractor is good, very smooth and no sag but found I had to mount the one on the 6" reflector upside down, (focus knobs on top), as the weight of the Canon 300D did cause a sag if it was mounted the other way. Pretty good value for the money overall though.

Bill

toryglen-boy
16-03-2009, 06:28 PM
thanks you gents

;)

stringscope
16-03-2009, 08:26 PM
Hello Duncan,

Interesting question. I guess "good quality" depend on what the focuser is being used for , ie visual only, imaging with a web cam or imaging with a heavy camera, and your desire for finely machined accessories. The higher quality units can end up costing more than some scopes. I did a quick $ check on the web and depending on specifications and including shipping the prices (at the current exchange rate :sadeyes: ) look something like this in descending order of quality IMHO:

Van Slyke "If you need to ask $......." http://www.observatory.org/scfmacro.htm
Feathertouch abut $600AUD+, http://www.starlightinstruments.com/
Moonlite about $500AUD+ http://www.focuser.com/
Astrosystems Phase 4 $300+AUD http://www.astrosystems.biz/focm1.htm
GSO - as Astronut says, about $120 - $150AUD depending on supplier.

I have Astrosystems, Moonlite and GSO crayford focuser units here and the GSO works quite nicely. However, IMHO, the other two are better engineered and "nicer" to use.

Cheers,

marki
16-03-2009, 11:08 PM
I have a couple of moonlites on different scopes. One is manual 8:1 reduction and one is driven by a stepper motor setup. They are very nice indeed but will cost a bit with the current exchange rate. I paid more then $500 for each of mine even when the currency was good but they were customised to my specs. You can get them directly from moonlite or through Steve at my astroshop. If its for a refractor, the williams optics focuser's are quite good if you can get hold of one. I think they now sell them seperately ?

Mark

Quark
17-03-2009, 08:06 PM
Hi Duncan,

If you have any thoughts about maybe hanging a camera or CCD on your scope then I would suggest giving consideration to a motorized version.

I have a JMI Moto focus on my 16" Newt and hang a Barlow, filter wheel and CCD on it with no problems. The focus can be used manually with either a high or low ratio adjustment or by adjusting one thumb screw it can be used as a Moto focus via a plug in remote control hand piece. Having a remote means of focusing a CCD image at very high magnification makes life a lot easier.

The only time I use it as a moto focus is for photography, but it is worth a thought.

Regards
Trevor