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Half the Battle is the Focuser.


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Very first telescope I owned, a 60mm refractor made by Tasco, back in the early 80s, that had an R&P focuser :)

I think virtually every scope had a R&P focuser back then :)

The crayford design started with the Amateur Telescope Makers I seem to recall, invented by a guy called John Wall I think. There were plans for one made of Meccano in one magazine way back !

Before you knew it, everybody wanted one, then everybody wanted one cheap and the Chinese manufacturers caught on which is, I suspect, why we are where we are today :)

Edited by John
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So many scopes are advertised as having crayfords these days and to be honest a cheap crayford is just as bad as a cheap rack and pinion from my experience, just cos it says it has a crayford doesnt mean to say its good.

Give me a quality Vixen R&P over most low to mid range focusers any day

IMHO

The best focuser is the feather touch, I have one on my FLT98 and its a dream and yes its a R&P.

The nicest crayford is the Badder Steel track with the Moonlite very close behind.

However with a bit of fettling on a milling machine the cheaper focusers can be made to work a little smoother and a little more positively but thats time and money which would be best spent on a better focuser to begin with.

Lets hope the new generation of super R&P focusers that maufacturers are developing are properly designed and work.

Philj

I bought a baader steel track for SCT last month, was a toss up between that and moonlit but price sprung it.

First time I used it and put a small camera it went all sloppy. However I looked on here for info and tightened 3 of the screws and it seems fine now but I'm wondering if I should have gone with the moonlite as I prefer the colours and look :)

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I have restored my 70's Tasco scope to full working order and repaired the F/5 as well.

I have decided to stick with the stock R&P focuser (re-greased).

I find it a joy to use. I actually really enjoy battling to get focus perfect. I enjoy everything wrong with my scope (wierd but true).

Part of the fun is fixing vibrations, focusing, re-focusing. If I had a perfect focuser I would probably get bored quick.

(I love using others' perfect focusers but on my scope = NO WAY!)

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... then everybody wanted one cheap and the Chinese manufacturers caught on which is, I suspect, why we are where we are today :)

Precisely :)

The basic focusers supplied with most telescopes sold today exist because most owners don't want to pay the extra required for a SteelTrack, Moonlite or Feathertouch. To be fair, I would much rather start with a Evostar-80ED then upgrade the focuser (mine has a SteelTrack) than buy something with a machined tube and over-sized Crayford but inferior optics.

Crayford or R&P is almost irrelevant, it is how they are made that matters.

Personally I like the idea of OTAs being supplied with and without focusers but I doubt it will become common practice.

HTH,

Steve

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However, what is the advantage of a Crayford over an R and P supposed to be?

Olly

It is easier to make an 'affordable' Crayford focuser with a smooth and precise focus action. When considering load-bearing capacity the R&P has the edge but it needs to be expensive/well-made (Feathertouch) if it is to offer the same smooth focus action as a Crayford. Cheap R&P focusers are horrible.

HTH

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It is easier to make an 'affordable' Crayford focuser with a smooth and precise focus action. When considering load-bearing capacity the R&P has the edge but it needs to be expensive/well-made (Feathertouch) if it is to offer the same smooth focus action as a Crayford. Cheap R&P focusers are horrible.

HTH

Yep, if you look on the starlight instruments website, the 2inch feathertouch rack&pinion is a lot more expensive than the 2 inch crayford feathertouch.

In other words making a r&p well seems more expensive than making a crayford well.

Edited by TheMightyKong
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I have a Moonlite for the C11, it is a very good unit, I also have a GSO sct focuser, it worked well out of the box, after finding some overhaul info on the net and adjusting it it now works perfectly, the same with focuser on my 200pds, after following the astronomy shed videos on tweaking it's now a joy to use. I think the cheaper focusers are a viable alternative for a limited budget if you are prepared to take a bit of time to strip them down and sort them out. Which is better than sitting in front of the tv on a cloudy night.

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Am I the only one that uses an orion(US) accufocus? It works great with the R&P that came with my omni120 and a lot less expensive then some of the focuser upgrades mentioned above. I can even switch it over to my XT10 if desired.

Eric

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In this latest R&P versus crayford debate, we are overlooking the fact that one manufacturer actually puts a very good crayford focuser on a scope and at a reasonable price, the TAL100RS, this unit although only single speed (less complicated) is machined from steel, with roller bearings, and has simple adjustments, that work. If Tal were to market this unit for other refractors it would be a very good choice

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In this latest R&P versus crayford debate, we are overlooking the fact that one manufacturer actually puts a very good crayford focuser on a scope and at a reasonable price, the TAL100RS, this unit although only single speed (less complicated) is machined from steel, with roller bearings, and has simple adjustments, that work. If Tal were to market this unit for other refractors it would be a very good choice

Thats a good point. The Crayford on the TAL Apolar 125 was one of the best engineered parts of the scope T thought.

As it happens I've just taken delivery of a used William Optics Zenithstar 70 ED which seems to have a very smooth 2-speed crayford. I've just been testing it with my 31mm Nagler and it holds it just fine with no "creep" when the scope it pointed at the zenith. I guess this one is adjusted "just right" - hope it stays like that :)

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