On Nov 1, 2021, at 12:44 PM, Ovanaelst@... wrote:

Hello 贵谤é诲é谤颈肠

?

Thanks for the feedback. Good idea for the etalon. I’ve heard of the Howie Glatter sling as well as of whiffletree. Something to consider if it makes a significant difference. My mirror is 50mm thick and I heard they are more important for thinner mirrors.?

?

The etalon to centre the mirror is a great idea, I’ll do that!.

Thanks?

?

Van:?[email protected]<[email protected]>?Namens?贵谤é诲é谤颈肠 Ruciak
Verzonden:?maandag 1 november 2021 9:31
Aan:?[email protected]
Onderwerp:?Re: [ObsessionUsers] Sling adjustment on obsession classic 18"

?

Hi Olivier,?
I own a classic 15 and UC22. All the indications are highly relevant but I add a few things from my own experience.
As the mirror will be out for a while you might consider replacing the original kevlar sling by a Howie Glatter sling (google it). It is a real master piece of mechanics that guarantees that the mirror is always suspended with the cable sling strictly parallel to the main surface of the mirror. If you consider it there are several sites giving you the right place to put the cable at the center of gravity of the mirror according to the f ratio and diameter.??
To center the mirror and repeat it precisely each time I move my scopes, I use cardboard "etalon" that I tuned in width after centering the mirror precisely once (according to the initial setup sequence proposed by Dave). When I setup I use these "etalon" to recenter the mirror, the etalon being inserted between the mirror box wall and the edge of the mirror on each side. Doing so I consistently reproduce the same collimation parameters (primary at the same place, tubes numbered and put at the same place, etc) leading to a fastest and consistent collimation achievement.

Hope this helps,
贵谤é诲é谤颈肠?

---

Dit e-mailbericht is gecontroleerd op virussen met Avast antivirussoftware.?