Canon M mount and PST

[Oldfort]

I have a canon M camera, and I was trying to use it for some imaging with my PST.  I have the T ring so connection to the PST is not a problem.

Starting with the  camera my set up is

Camera -> EFM to EF converter -> T-ring -> T adaptor (1.25") -> PST

I can't get anywhere near focus.  Any thoughts on what I should try next or am I doomed to fail on this approach?

 

Thanks

[NiCo10]

Have you tried with a Barlow as well?

[Oldfort]

2 minutes ago, NiCo10 said:

Have you tried with a Barlow as well?

No, not yet.  I will give it a go.

 

Thanks

[Oldfort]

I have now tried the coronado barlow, but without success.  I will keep on experimenting.

[Merlin66]

Unfortunately the PST was designed for visual observing, not for imaging.

The favourite solution is to use a Barlow lens at the base of the eyepiece holder to push the focus far enough above the eyepiece tube to allow the camera to focus.

This seems to work with webcam type camera, your Canon M may require more ingenuity.

[David Smith]

I used to image with my PST connected to a DSLR via a barlow. Not ideal but it worked. EOS M cameras have a shorter focal path (no mirror in the way) but then you have the EOS-M to EF converter in there instead so probably works out very similar.

[Oldfort]

37 minutes ago, David Smith said:

I used to image with my PST connected to a DSLR via a barlow. Not ideal but it worked.

Do you recall what make of Barlow?  As I said, I couldn't get focus with the coronada one.  Equally likely is user error.

[Merlin66]

Sylvain Weiller has details - down the bottom of this (very interesting) page

http://sweiller.free.fr/ATM/PST-EOS.html

[David Smith]

7 hours ago, Oldfort said:

Do you recall what make of Barlow?  As I said, I couldn't get focus with the coronada one.  Equally likely is user error.

It was just a cheap-ish Revelation achromatic 2x barlow like this one:-

https://www.rothervalleyoptics.co.uk/revelation-astro-2x-barlow-lens.html

[Oldfort]

Well, I'm making progress, with barlow optics screwed directly to nosepiece of T ring.  I have a shorter nosepiece on the way, so maybe that will help even more.

[David Smith]

Looking more like it.