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View Full Version here: : Budget Focuser Options for 200mm f5 Newtonian


Benno85
29-11-2009, 04:21 PM
Howdy Folks,

For those that have upgraded the focusers on a newtonian so that focus can be achieved using a DSLR, are there any "budget" options out there? I see brands like Moonlite and Feathertouch, but are there an cheaper generic brands out there that offer a decent start??

erick
29-11-2009, 10:47 PM
Do you mean, a budget item apart from a low profile GSO focusser? And pushing the primary mirror further up the tube on the existing collimation screws or new longer ones?

Benno85
30-11-2009, 08:03 AM
Hi Eric,

I wasn't aware that GSO offered a low profile focuser, but that was what I was trying to get at :)

Basically I don't want to bring the mirror up the tube by cutting the OTA, but if longer collimation bolts will do the same thing then that may be the cheapest way to go (as opposed to the GSO focuser)

alfi
30-11-2009, 08:47 AM
hi
orion and skywatcher also have low-profile 2 speed focusers for newts.

alfi

erick
30-11-2009, 10:31 AM
Well I was sure GSO did, but I cannot see it on the Bintel site at the moment??? OK, I can see it on the Andrews Communications site. Height 32mm, cf 52mm standard focusser.

If you do some searching, there was a report of replacing the collimation bolts with longer bolts and springs to move the mirror several cm up the tube. Apart from the bolts being rigid so the primary doesn't "wobble", the only issue I can think of might be a bigger diameter light cone at the secondary spilling over the edges - a bit of light loss?

Benno85
30-11-2009, 11:19 AM
[QUOTE=erick;528721]Well I was sure GSO did, but I cannot see it on the Bintel site at the moment??? OK, I can see it on the Andrews Communications site. Height 32mm, cf 52mm standard focusser.
/QUOTE]

That's what I'm searching for mate, thanks very much. :thumbsup: I might give Luke a buzz and see if that is a small enough profile to achieve focus through a DSLR.

Ian Robinson
30-11-2009, 07:27 PM
How about a 2" ultra low profile helical focusor ?

A few places in the USA still do them and they are cheap .

bmitchell82
01-12-2009, 04:56 PM
be careful with your focuser if you plan to do photography, you can put yourself in a whole world of hurt when it comes to "budget" focusers. how do i know, :) i am one of those people. im saving my roubles for a good focuser! it makes the difference

mental4astro
02-12-2009, 11:19 AM
Look here:

http://www.1800destiny.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=1D&Product_Code=FOCH

Not for photo applications though if that is what you are after.

I might get a couple for some projects I have kicking around.