Minimum limit to telescope magnification

No problem. Practical stuff first. Do you have a 1.25 inch focuser or a 2 inch focuser?


>Okay, I didn’t know that. But is there a simple explanation for why that is so?

Don’t think I saw this stated quite so simply in the thread, so:

If your telescope magnification is X, the angles of rays exiting the eyepiece will vary by X times whatever the angles of rays entering the objective do. And, the bundle of parallel rays exiting the eyepiece will have a diameter that is 1/X times the diameter of the bundle of parallel rays entering the objective.

But as I think about it it isn’t obvious what to say about why that is. If I think of it, though, I’ll post it.


In that case about the longest focal length eyepiece you can go is 35mm.

If you really want a wider field of view, its almost cheaper to just buy a 4 inch to 6 inch f6 or so mirror and build yourself another smaller telescope.

I’d be tempted to buy a 4 inch f6 mirror to use with your 25 mm eyepiece rather than a 35 mm eyepiece.

A second much smaller scope is quite handy for traveling, camping, and impromptu observing sessions.