I got first a magnifier and only then I started searching for red dot to pair. Don't ask me why I got it reversed, it is a complicated story.
Anyway, I was playing with four brand/models new out of box, and every each was showing the artifact, the same as people with astigmatism referring to.
Only difference I could make a picture of the shape with my cellphone also with my DSLR camera, also when I was rotating the scope + magnifier combo on the rail the image was rotating....so its not my eyes beside a fact me 60 yo.
So finally (usually I don't bother her with my new toys
) I decided to tell this story to my wife...she know everything
But don't laugh! She is working for an optics manufacturing in ITAR, she is an ME for "those" lenses.
She is telling me this is a flaw in material and processes which brand what type of coating using in their optics.
Now, what I did I combined two optics, the red dot + a magnifier, the x6 power magnified the flaws from both units/glasses...
How can you help yourself, even you have astigmatism? Get a polarizing lens, something like the camera polarizing lenses (and btw years ago I did an extensive study on those as well, do not expect a better quality from a higher priced lens, that is false and bs marketing).
With my eyes, I just grabbed my fishing sunglasses, those have some sort of polarizing as well, but not meant to do anything better then fishing. It helped my eyes filter out the artifact.
So you can go ...my first idea...to a shopping mall to those sunglasses booths and try out several combinations with your red dot. Or find in optics stores (like Henrys or similar) and ask them for a filter size you can screw in into your unit, would that be 30 or 32 mm or whatever. Or if you can get to a collector or used camera stores, ask them for filters from old camcorders, those had about a same size filters and threads...
Or you get yourself a prism scope, that is also some sort of "red dot" as well but different technology, also less friendly with parallax.
This what I am after now for my new PP750, my Sig red dot is just way to bulky for a pistol.
Well purpose of magnifiers wasn't really for precision. It was just a method of repurposing a optic and making it more versatile. Like 4x is great for open field, suck for CQB.. Where a 1x RDS is perfect for CQB, but lacking on open field. It was a solution to have best of both worlds. Ability to shoot CQB and then flip for longer shots. Regular soldiers, don't worry about parallax, because they're not snipers.