2" r&p and Caryford focusers

Hi everybody,

I was wondering if anyone has used the 2" r&p focuser sold by OVL,
see:

http://www.opticalvision.co.uk/products.asp?D=65&P=225

or the one shipped by TS:

http://www.telescope-service.com/ATM...ers.html#foc2u

Are these sourced from the same maker?

Also, has anyone seen/used this Crayford, again supplied by TS:

http://www.telescope-service.com/ATM....html#tsoaz2cn

Does anyone know anyone who makes low-profile r&p and Crayford
focusers, or for low profile focusers is one stuck with a helical? Am
looking for recommendations - more specifically what *not* to buy in
the budget/moderate price range ...:-). Thanks.

Dave Randell

"David Randell" wrote in message
om...

Hi everybody,
I was wondering if anyone has used the 2" r&p focuser sold by OVL,
see:
http://www.opticalvision.co.uk/products.asp?D=65&P=225

Yes - I have two, including the one on my Helios 200mm f5 Dobsonian. The
only problem is that 2" designation. After ~2 months and reminders, I'm
still waiting for Warehouse Express to supply the part to allow use of 2"
eyepieces in it. As supplied it only takes 1.25" eyepieces. (I've now had
a suitable 2" sleeve made locally (Astroparts) and it works well for my
needs. It allows me to use, and parfocally, one of those 30mm 80degree
eyepieces. Bless the Chinese for making wide-field viewing affordable!)

or the one shipped by TS:
http://www.telescope-service.com/ATM...ers.html#foc2u

Pretty certain that I also have one of these (bought hoping it would fit my
Dob. It won't, without enlarging the fixing holes, and the curve is wrong
for my tube.). Major problem is that the 1.25" adaptor places the 1.25"
eyepiece a further 10mm (as per desription) from your mirror, so it's not
parfocal between eyepiece sizes. It feels better than the 1st. item, and is
a different design, but has the same thread size so eyepiece holders can be
swapped from one make to the other.

All three in my possession are different.
In terms of firmness without excessive clamp screw tightening, the order
from worst to best is :-
1 Original r&p on my OVL Dobsonian. Definitely sloppy.
2 Near identical OVL r&p focuser bought recently from Warehouse Express, but
much more useable due to extra bearing sleeve.
3 TS version. Best of the bunch - if only it fitted my tube.
(Both 1&2 take T mount adapters allowing SLR photo use.)


Hope this helps

--
M Stewart
Milton Keynes, UK
http://www.megalith.freeserve.co.uk/oddimage.htm

"Malcolm Stewart" schreef in
bericht ...
Yes - I have two, including the one on my Helios 200mm f5 Dobsonian. The
only problem is that 2" designation. After ~2 months and reminders,
I'm
still waiting for Warehouse Express to supply the part to allow use of 2"
eyepieces in it. As supplied it only takes 1.25" eyepieces.

The 2" adaptor was supplied together with the scope (also 200mm f5 Helios,
but on an EQ-5) in my case. So did they forget to include it in your case?

Something I'd like to know about this focusser:

I'm kind of a newbie, but I think this focusser is a bit hard to operate. I
believe I read somewhere that it is advisable to take it apart and replace
the grease. Does anyone have any suggestions and/or recommendations? Do's
and don't's?


Regards, Bas.

DO! It's easy. Clean out the sticky Chinese junk and put a bit of lithium
grease---huge difference.

Doink


"bpsdg" wrote in message
i.nl...

"Malcolm Stewart" schreef in
bericht ...
Yes - I have two, including the one on my Helios 200mm f5 Dobsonian. The
only problem is that 2" designation. After ~2 months and reminders,
I'm
still waiting for Warehouse Express to supply the part to allow use of 2"
eyepieces in it. As supplied it only takes 1.25" eyepieces.

The 2" adaptor was supplied together with the scope (also 200mm f5 Helios,
but on an EQ-5) in my case. So did they forget to include it in your case?

Something I'd like to know about this focusser:

I'm kind of a newbie, but I think this focusser is a bit hard to operate.
I believe I read somewhere that it is advisable to take it apart and
replace the grease. Does anyone have any suggestions and/or
recommendations? Do's and don't's?


Regards, Bas.