Cak scopes?

[Eccy]

Hello to all!

I am new to the site & am a pst viewer & love the scope. I am really curious about the cak scopes (Lunt, Coronado?) any advice from owners or any experienced observers. Many thanks for time and advice!

[brianb]

The Coronado PST CaK is no longer available AFAIK - you might be able to pick one up second hand, though.

The Lunt CaK diagonals work well - if you have a decent refractor up to 4" / 100mm aperture and with a 2" focuser.

[Eccy]

Thanks Brian!

I was looking @ the dedicated Lunt cak scope but I havent got a night scope, still trying to decide!?

Is it possible to use a maksutov / smict cassegrain with a cak filter?

Cheers again!

[brianb]

Is it possible to use a maksutov / smict cassegrain with a cak filter?

No - the full solar power arrives at the front side of the CaK diagonal and you will fry the secondary mirror for sure.

The Baader CaK filter has too wide a bandwidth to be useful, the view it gives is essentially the same as white light.

I take it you're aware that most people see very little in CaK, which is very close to being ultraviolet. I see nothing at all ... until I hang a camera on the scope instead of an eyepiece.

Lunt sell a 60mm scope with a CaK diagonal ready fitted ... this works; the diagonal can be replaced with a normal star diagonal for "night" observations.