Dioptrx and Paracorr

[rrussell1962]

I have an old 2 inch Skyglow filter lying around and have just noticed that if I unscrew the dioptrx into the 2 component parts, one side screws into one side of the filter housing and the other side of the filter housing screws into the bottom of the paracorr. Is there any reason why I can't leave the dioptrx attached to the paracorr and just rotate the paracorr in the focuser to eliminate the astigmatism?

[tempestwizz]

It is my understanding that the dioptrix needs to be the final part of the optical train, ie between the eyepiece and your eye. If you put the dioptrix on the Paracor before the eyepiece I don't think the optics are the same. You can always suck it and see.

[rrussell1962]

That would make sense, I may give it a go though just to see if it does result in a decent image. Update, Don Pensack on CN has just explained why it is a daft idea!