SXBB

These are exactly the same questions that I had when I received mine and I didn’t have the cycles to follow it through. Not only which connectors to use but exactly where the ronchi needs to be placed in order to work. If you look at the instructions I believe it says something to the effect of putting it in front of a camera with a normal lens in order for you to get it to come to focus?
 

Best,

Bruce

There may be another way. I’ve read of people using two scopes and an artificial star in order to increase the optical distance. If I am correct which I’m not sure of actually, one of the telescopes is focused at infinity and the artificial star is placed in front of the objective of that scope.  The other telescope which is the one that you want to collimate is placed in front of that scope and then focus on the artificial star can be achieved.  I think it’s called a double pass system. I have looked for more detail on this and come up empty but maybe somebody here might be able to fill in the blanks?

Cheers,

Bruce

On 13/06/2020 at 03:33, Fellside said:

Bruce

You are probably correct. F/L varies between batches. The Ronchi eyepiece should allow the user to set the correct F/L to suit there instrument. Whatever it is.

What problems did you encounter when using the Ronchi?

Graham

Hi Graham,

I found the instructions lacking regarding how to position and use it with a camera. I attempted to use it but didn’t have a DSLR with a normal lens at my disposal which I suspect was the problem. I’d greatly appreciate someone illustrating how to set it up with a ccd or cmos Camera! A thread on setting up a basic optical bench would also be wonderful!

Best,

Bruce

I purchased the Photographic Ronchi to hone in on the correct distance for my RC10 but have had difficulty using it so I'm very interested in the experience of others.

As for the correct Focal Length, my understanding is that it can be slightly different for each batch of mirrors so a generalization of the correct Focal Length may be off the mark.

Thanks,

Bruce