Astrograph Collimation

[astrosathya]

I have tried a million times to collimate my 6inch f4 astrograph. I've always got skewed stars on the top right of every image. Though, according to many many websites, below is the pattern I need to see if the scope is collimated. Could anyone else please concur that below is what you see when you look into a Cheshire? Please note the offset mirror because the scope is designed for astrophotography

[Buzzard75]

I'm sure you've already looked at Astrobaby's guide, but I'll post it here anyway. While it is common for the secondary mirror to be offset in an f/5 or faster scope, I don't see your primary clips so I don't know how well you're secondary is centered on your primary. Suggest backing your focuser out so you can get a better view of the whole secondary and see the primary clips.

http://www.astro-baby.com/astrobaby/help/collimation-guide-newtonian-reflector/

[andrew s]

I think f4 is too fast to collimate just with Cheshire. You need an auto collimator to do the final adjustment.

Have you tried this?

Regards Andrew 

[astrosathya]

On 30/01/2019 at 23:27, Buzzard75 said:

I'm sure you've already looked at Astrobaby's guide, but I'll post it here anyway. While it is common for the secondary mirror to be offset in an f/5 or faster scope, I don't see your primary clips so I don't know how well you're secondary is centered on your primary. Suggest backing your focuser out so you can get a better view of the whole secondary and see the primary clips.

http://www.astro-baby.com/astrobaby/help/collimation-guide-newtonian-reflector/

I use a long Cheshire and even if rack out the focuser completely, even then I cannot see the whole secondary. Its too huge as its designed to accomodate an array of accys for imaging. Yes, I've followed astrobaby's methos itself. 

[astrosathya]

On 30/01/2019 at 23:28, andrew s said:

I think f4 is too fast to collimate just with Cheshire. You need an auto collimator to do the final adjustment.

Have you tried this?

Regards Andrew 

I am yet to invest in an auto collimator. Short of funds