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Old 25-04-2019, 09:23 PM
knightrider
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knightrider is offline
 
Join Date: Jan 2013
Posts: 136
The SW 10" goto dobs fortunately already come with thumb screws/knobs for both the collimating and locking screws for the primary.

On the unfortunate side, collimating newts take a bit to get your head around initially, but once you get it sorted what's happening it's not that bad.

Rolling your dob out on a trolley over bumps wouldn't hurt your collimation, unless your running it out like a Jamaican bobsled team practicing on a dirt road or trying to see how much air you can get when you hit a bump.

On the topic of laser collimators... These in themselves actually have their own collimation grub screws to align the laser, and seem to not be accurately aligned when they're purchased. Especially the generic type laser collimator that is widely available.

This link will help you collimate your collimator... http://www.stark-labs.com/craig/llcc/llcc.html

So that may be why it seems to have changed when you re-insert the laser.

I use both a cheshire and laser. The cheshire I use to make sure my secondary is positioned centrally, and also to confirm my laser has done a satisfactory job.

Cheshire and Laser collimators aside. Ergh... both of these will give you different/disagreeing results if you try to cross reference them unless you square up your focuser first. Your SW Crayford Focuser has it's own alignment locking and grub screws so you can square up your focuser with the tube.

The good thing is it's not necessary to ensure your focuser is absolutely square. It just does your head in when you can't figure out why your secondary mirrors position looks so out of place when you sight through a cheshire after collimating with a laser. I squared mine because I'm pedantic about my cheshire & Laser results matching, not because it's required.
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