开云体育

---------- Forwarded message ---------
From: Carl <carljtj7@...>
Date: Fri, Sep 6, 2024 at 10:07?AM
Subject: 12.5 inch secondary positioning
To: <ObsessionUsers@groups.io>

Unable to situate secondary in relation to focused so as to able to center laser dot on both mirrors AND have all the primary show in my Farpoint. Have tried shimming the focuser and repositioning secondary via loosening central holding bolt. Dave Krieg suggests bending spider vanes. No stomach for that just yet.

Page in my manual aftet the attached on secondary was not included, when scope shipped.

Any suggestions?

Hi Carl,

I had what I think is a similar problem with my UC-22.? I was unable to line up the red dot coming from my?Howie Glatter Laser collimator with the mark in the middle of the secondary.? The?scope worked OK with?that malalignment, but I knew something was wrong, and maybe the telescope?images could improve if I fixed the problem.??

I decided to try and fix it after reading about your woes.? I put the secondary ring on the?counter and I tried loosening the?wing nut and adjusting the?three long tilt adjustment screws to tilt the?secondary.? I got it almost lined up, but the?secondary was obviously very crooked and one of the screws was backed out all the way leaving no room for further adjustment. That just wouldn't do.? ?I then consulted with an engineer friend who also?owns a UC22, who suggested equalizing the length of the tilt adjustment screws, tightening the wing nut back to the start and then loosening the left and right nuts on the base of the feather touch focuser, leaving?the center bolt and nut minimally loosened.? ?I was then able to easily 'aim' the?focuser with the laser dot collimator in place, and get the red dot?exactly?in the?middle of the?machined?dot in the center of the secondary.? The secondary was not crooked, and I was also left with plenty of threads to?adjust the?secondary tilt on each of the three adjustment screws.??

I assume that when I assemble the scope I will be able to center the red dot in the center marker(paper washer) of the primary using the three tilt adjustment screws of the secondary, and then change from the laser dot to the laser bar-shape fitting of the collomater. load it onto the collomater tube with the white tilted screen and? center hole, and adjust the primary's screws to attain perfect alignment and collimation. (using the primary's?screws to move the ring of the paper washer to fit around the hole in the center of the white screen).

Sorry for?all the details.? I hope this helps.

Gene

On Fri, Sep 6, 2024 at 7:51?AM Carl via <carljtj7=gmail.com@groups.io> wrote:

---------- Forwarded message ---------
From: Carl <carljtj7@...>
Date: Fri, Sep 6, 2024 at 10:07?AM
Subject: 12.5 inch secondary positioning
To: <ObsessionUsers@groups.io>

Unable to situate secondary in relation to focused so as to able to center laser dot on both mirrors AND have all the primary show in my Farpoint. Have tried shimming the focuser and repositioning secondary via loosening central holding bolt. Dave Krieg suggests bending spider vanes. No stomach for that just yet.

Page in my manual aftet the attached on secondary was not included, when scope shipped.

Any suggestions?

Hello Gene,

First, thanks so much for taking the time to share your experience with me.? Your situation, as you describe it, very much matches my own.? In fact, what you suggest as remedy is what I employed over the weekend.? The essential step was backing off the nuts on one side of the focuser, placing a nickel and washer as a shim under that side to tilt the focuser a bit, and retightened the holding bolts.? This allowed me to relax the tortured position of the secondary I had to use to get it collimated. Single red dot near center of secondary.? So, I used it the last couple nights and am pleased with the results.

Kind Regards,

Carl

Ledyard, CT

On Sun, Sep 8, 2024 at 9:09?PM Gene Fioretti via <gpfioretti1950=gmail.com@groups.io> wrote:

Hi Carl,

I had what I think is a similar problem with my UC-22.? I was unable to line up the red dot coming from my?Howie Glatter Laser collimator with the mark in the middle of the secondary.? The?scope worked OK with?that malalignment, but I knew something was wrong, and maybe the telescope?images could improve if I fixed the problem.??

I decided to try and fix it after reading about your woes.? I put the secondary ring on the?counter and I tried loosening the?wing nut and adjusting the?three long tilt adjustment screws to tilt the?secondary.? I got it almost lined up, but the?secondary was obviously very crooked and one of the screws was backed out all the way leaving no room for further adjustment. That just wouldn't do.? ?I then consulted with an engineer friend who also?owns a UC22, who suggested equalizing the length of the tilt adjustment screws, tightening the wing nut back to the start and then loosening the left and right nuts on the base of the feather touch focuser, leaving?the center bolt and nut minimally loosened.? ?I was then able to easily 'aim' the?focuser with the laser dot collimator in place, and get the red dot?exactly?in the?middle of the?machined?dot in the center of the secondary.? The secondary was not crooked, and I was also left with plenty of threads to?adjust the?secondary tilt on each of the three adjustment screws.??

I assume that when I assemble the scope I will be able to center the red dot in the center marker(paper washer) of the primary using the three tilt adjustment screws of the secondary, and then change from the laser dot to the laser bar-shape fitting of the collomater. load it onto the collomater tube with the white tilted screen and? center hole, and adjust the primary's screws to attain perfect alignment and collimation. (using the primary's?screws to move the ring of the paper washer to fit around the hole in the center of the white screen).

Sorry for?all the details.? I hope this helps.

Gene

On Fri, Sep 6, 2024 at 7:51?AM Carl via <carljtj7=gmail.com@groups.io> wrote:

---------- Forwarded message ---------
From: Carl <carljtj7@...>
Date: Fri, Sep 6, 2024 at 10:07?AM
Subject: 12.5 inch secondary positioning
To: <ObsessionUsers@groups.io>

Unable to situate secondary in relation to focused so as to able to center laser dot on both mirrors AND have all the primary show in my Farpoint. Have tried shimming the focuser and repositioning secondary via loosening central holding bolt. Dave Krieg suggests bending spider vanes. No stomach for that just yet.

Page in my manual aftet the attached on secondary was not included, when scope shipped.

Any suggestions?