I have to agree with David, I’ve had a Riccardi reducer for over a year and despite many attempts have yet to get satisfactory images. This “only” reduces the scope to f/4.1, but my stars are pointy on one side...
I bought the two adapters from TS and they are well made and fit perfectly, but it’s not an impossible task to get a single piece made locally. The reducer fits up inside the focuser tube. The spacing is not impossible to achieve, but does take some experimentation as precision is critical. So this is not exactly a plug and play option.
I also have an M48 tilt adapter and haven’t been able to eliminate the problem, so suspect that my reducer is at fault. I bought mine used from a trusted source so I have no recourse, but for my purposes it would be an expensive exercise to send it back to Europe for repair.
I should add that I’ve used both my ASI1600MM and ASI183MM and it’s noticeable with either.
Needless to say, my scope works perfectly at native focal length, so that’s what I stick to. The Esprit 100 is an excellent scope, and I’d imagine an ASI2600MC would be an awesome match
