Collimation of SCT using laser!!

[Mac]

you have never been able to use a laser collimator to align the secondary mirror of an SCT
as the secondary is always slightly off!!

Using one of these will normally destroy any collimation.

UNTILL NOW.

Just found this site which describes how to use a laser to aid collimation.

Simply
You project the laser onto a target on a wall, and adjust the mirrors,
then recenter the target and repeat.

Full details are here.  http://www.kendrickastro.com/astro/pdf/sct_collimation.pdf

Might try this later.

[PhilB]

That's very interesting, Mac. I was once sold a laser by a well known telescope importer specifically for use on an SCT! Never could get on with it; went back to using star testing. Now I know why!!

[The Thing]

Same here, Tscope Hse I think they were called, before they became a farm yard occupant. Sold the laser collimator on eBay eventually for £10 less than I paid.
This gadget looks very interesting. Currently I use a mask with three slots around the periphery to collimate my sct at x400 magnification on a bright star. Seems to work very well.