Collimation fustration!!!

[wookie1965]

Thanks wookie1965

I will check again.

If it is indeed out as it appears on the photo -what do I do?

I can't move the primary because it will then move away from the centre?

Or is it the case of having to tweak secondary?

Like Carl said i was showing you what to look at,  you can look straight down and see if the gap is the same if it is great if not yes the secondary will need to be tweaked

[Jason D]

Offsetting the secondary mirror away from the focuser does not impact the cone of light as the author asserted. I have more info in the following post:

http://stargazerslounge.com/topic/181569-collimation-focuser-alignment/?p=1882108

Jason

I don't know if I can ask a question re this new post? Jason mentions DSC readings. What are these, please? This forum's abbreviation list doesn't and Google comes up with Differential scanning calorimetry!!

Thanks

Steve

Steve,

DSC stands for Digital Setting Circles

http://en.wikipedia.org/wiki/Setting_circles

Google "DSC Telescope"

Jason

[Jason D]

The part coloured in should be the same distance all round yours is a bit wider at the bottom other than that your spot on.

I believe the mirror position and collimation looks good. Trying to shift the secondary mirror sideways would require adjusting the spider vanes or the focuser. Not worth the effort. Positioning the secondary mirror under the focuser is the least critical collimation adjustment.

Here is a photo from my scope. Ideally you want the primary mirror reflection and the secondary mirror to coincide.

By the way, I take my photos using a tripod. Here is an interesting photo:

[bambuko]

Yes... I think the mistake I have made was to start by adjusting spider vanes to get secondary central in the tube (all vanes equal to within .2mm using vernier caliper).

I am happy with my collimation for now and will wait for clear skies to judge the result