Meade 1209 and ETX

Hey folks,

I'm having trouble getting good focus with my ETX90 and ST7. I can
physically reach focus, but image shift is killing me! The image goes
from one edge to the other on the CCD when I change directions.

Has anybody tried a Meade 1209 or equivalent Crayford focuser on an
ETX90 ? I have the ETX-to-SCT adapter and a 2" visual back with t-thread
to make the connection right now. I was thinking of getting rid of the
visual back and using the 1209 instead. Anybody tried this ?

Eric.

Eric wrote:
Hey folks,

I'm having trouble getting good focus with my ETX90 and ST7. I can
physically reach focus, but image shift is killing me! The image goes
from one edge to the other on the CCD when I change directions.

Has anybody tried a Meade 1209 or equivalent Crayford focuser on an
ETX90 ? I have the ETX-to-SCT adapter and a 2" visual back with t-thread
to make the connection right now. I was thinking of getting rid of the
visual back and using the 1209 instead. Anybody tried this ?

Eric.
The Crayford style focuser is your ticket to happiness, JMI and the 1209
are superb at this.By the way, have you tried tapping the scope with
your hand, a nice firm slap, not a hammer blow, with the mirror just at
its farthest point down or out to settle the mirror? Any time you
focus, especially for CCD , you should focus by moving the mirror
inwards, very slowly,keeping in mind that the last thing you want to do
is to have to back up.Practice this technique untill it becomes second
nature, and when you do get one of those Crayford focusers, your
focusing routine becomes not a chore,but a habit.Hope this helps.