What is the meaning of drawtube is 2" format?

mrngbss · Post by **mrngbss** » Tue Jun 12, 2007 11:38 pm

I was looking at the JMI EV-C focusers. I had asked a few questions on drawtube length. I received a reply from their staff stating that "Our drawtube is 2" format".

Does the 2" refer to the external diameter of the focuser drawtube or the internal diameter (something like what some of us use)? Is the drawtube on a WO Megrez or WO80FD a 2" format?

Anyone here has seen, touched, played or has one to share his/her experiences here? How does one attach a JMI EV focuser on a refractor?

All the jargons... aiyoh..

Meng Lee · Post by **Meng Lee** » Tue Jun 12, 2007 11:42 pm

should be the internal diameter is 2". Ya, their picture looks like 2" drawtube to me. Yes, WO Megrez is called "2" focuser" or 2" format. FLT 110 is called the 4" focuser or 4" format.

Meng Lee · Post by **Meng Lee** » Tue Jun 12, 2007 11:44 pm

attach to refractor? if you say WO80FD, then you need to buy the motor , not the focuser.

vhuang168 · Post by **vhuang168** » Wed Jun 13, 2007 5:57 am

The JMI EV focusers are mainly for Newts and Casses. I don't see 1 listed for refractors. They do list a motorfocus for the WO scopes. But there seems to be some things you need to check before ordering them. Check here. http://www.jimsmobile.com/spec_gso_wo.htm

If you want to replace the whole focuser, both Moonlite and Starlight (feathertouch) make adapters for WO scopes to use with their crayfords.

Vincent

mrngbss · Post by **mrngbss** » Wed Jun 13, 2007 8:54 am

JMI's website lists down in their comparisons page that the EV-1C series are used for Cassegrains and Refractors. Thus I was wondering how they are attached to refractors.
thanks!

Canopus Lim · Post by **Canopus Lim** » Wed Jun 13, 2007 2:24 pm

I have the JMI DX1 (the predecessor of the EV1) for Newtonian and it is less smooth than a fully functioning Moonlight (the Tri knob one) or Feathertouch. However, the JMI focuser gets the job done on a fast scope; that is to get critical focusing. It is smooth especially the fine focuser but not the smoothest focuser out there. Therefore, it would be better to get a Moonlight or Feathertouch. Anyway, the JMI DX1 matches in colour with my Obsession UTA.

rlow · Post by **rlow** » Wed Jun 13, 2007 6:29 pm

Thats right, though the JMI focusers are good, the Moonlite is better, and the Feathertouch is even better.

kingkong · Post by **kingkong** » Thu Jun 14, 2007 11:29 am

i'm getting a JMI-EV focuser for my LXD55. as long as it does the job... yes, i'm a cheap skate.

i got a gso 2-speed focuser for my c8, it's good for the job. i dont know how much smoother more money will get me but it does the job well enough. yes, i'm confirmed cheap skate.

Post by **weixing** » Thu Jun 14, 2007 12:30 pm

Hi,

i'm getting a JMI-EV focuser for my LXD55. as long as it does the job... yes, i'm a cheap skate.

i got a gso 2-speed focuser for my c8, it's good for the job. i dont know how much smoother more money will get me but it does the job well enough. yes, i'm confirmed cheap skate.

Don't like that la... I'm still using the original rack and pinion focuser...

Hmm... by the way, just wonder what is cheaper that a "cheap skate"??? "cheapest skate"?? Ha ha ha

Have a nice day.

rlow · Post by **rlow** » Thu Jun 14, 2007 1:52 pm

I don't think getting a JMI-EV qualifies a person as a 'cheapskate'... just look at the price!

Anyway I was using the DX1 last night and it is more than good enough for the job, if you are not too discerning in comparing with other focusers.