mirror shift

[sungrazer]

Hi

I have an LX200gps 10 f10.

I've been looking at using it for some photography but I am finding that when I slew from one object to another the focus shifts. Not such a big deal for visual but annoying - I have the mirror lock on so I am a little surprised as to how/why this occurs?

Can anyone direct me to a resource? - how can I tighten this up. I would have thought once I engaged the mirror lock the focus would hold from east to west.

thanks
Karen

[Merlin66]

Karen,
The slop/flop of the main mirror in an SCT can certainly be improved by running the mirror up and down the baffle tube; by rotating the focusing knob (about 30 turns) each way a few times.
This re-spreads the grease on the baffle tube and reduces the effective gap.

A routine job which should be done by all SCT owners at regular intervals.
Hope that helps.

[blink138]

that's good info ken!
pat

[multiweb]

Drilled the back cell on mine and I have three bolts going right through (http://www.astropic.net/astro/C11/product_pic/pictures/SCT_tilting_access.jpg). I get to focus then touch the bolts to the glass and it holds the mirror in place on three points.

[Merlin66]

Marc,
Yes, a possible solution for some capable members....
(Your link doesn't work for me?)

[multiweb]

Bummer... try this one.
http://www.astropic.net/astro/C11/article.view&productid=18

[Merlin66]

Hmmmm
Not a job for the faint hearted!!!

[sungrazer]

thanks Ken
Will give that a shot
cheers
Karen

[sungrazer]

Oh My..
Nice one
cheers
Karen