DIOPTRX™ Eyepiece Accessories > DIOPTRX™ > Reviews
From Our Blog
  • Tack Sharp Stars: Overcoming Eyesight Astigmatism (1/31/2019)
    Phil Ressler's had never seen pinpoint stars before DIOPTRX™. "For people like me, DIOPTRX™ is arguably Tele Vue's most essential product, because it makes all of Al Nagler's original work in eyepieces and refractors unmistakably worthwhile to the astigmatic viewer." He tells us how it works: "just turn the DIOPTRX™ lens slowly until, in an instant, the star is bang-on tight, and the astigmatic elongation is just gone. Impressive!"

— Dennis di Cicco. "Dioptrx: Prescription for Perfection". Sky & Telescope (July 2007). Full Review.

— Mike D. Reynolds. "The sharpest image". Astronomy (October 2006). Full Review.

— Todd Carlson. "Tele Vue’s Dioptrx: The Final Answer for Astigmatism?". SkyNews (January / February 2006). Full Review.
Star Party Comments

Enjoy the following sample comments sorted by astigmatism correction (some correctors mentioned may be discontinued and others added since this was compiled).

TSP = Texas Star Party, RTMC = RTMC Astronomy Expo, and CSSP = Cherry Springs Star Party



RTMC B.B. 0.25 Can't tell.
TSP A.D. 0.25Slightly better, noticeable.
RTMC B.P. 0.25Makes a subtle difference.
TSP J.S. 0.25Noticeable but not huge.
RTMC S.A. 0.5I like it.
TSP B.C. 0.5At least as good as glasses.
CSSP G.C. 0.5An improvement over glasses.
TSP P.C. 0.5Greater contrast, finer resolution.
CSSP W.C. 0.5Great, a lot better.
CSSP C.D. 0.5Wow -- makes a difference.
CSSP B.G. 0.5About the same as glasses.
CSSP K.G. 0.5Better than my glasses.
RTMC S.G. 0.5Simply marvelous.
CSSP J.K. 0.5Holly mackerel, very impressive.
TSP A.M. 0.5Clearer than without glasses.
TSP R.M. 0.50 Better resolution.
TSP S.M. 0.50Remarkably better.
CSSP B.P. 0.50Looks like it's sharper.
CSSP C.P. 0.50Wow!
CSSP C.S. 0.50Amazing, like being at doctor's office.
CSSP J.S. 0.50Outstanding.
RTMC T.S. 0.50WOW! Time to get the scope out, wonderful.
RTMC J.T. 0.50O-wow.
CSSP R.W. 0.50Amazing, incredible.
RTMC A.B. 0.75Wow-wee, looks like a champ.
RTMC B.L. 0.75Noticeable improvement
TSP G.M. 0.75Must have accessory
TSP K.M. 0.75Don't wear glasses. Much better. Helps tremendously.
TSP M.P. 0.75Definitely sharper than no glasses. Equal to eyeglasses but more contrast
RTMC J.S. 0.75Small difference, but better than glasses.
CSSP P.B. 1.00Helps.
CSSP L.C. 1.00Definitely better than glasses.
RTMC T.D. 1.00Definite improvement.
CSSP B.E. 1.00Wow - amazing.
TSP J.E. 1.00Significantly better.
RTMC B.H. 1.00Excellent, crystal clear.
RTMC D.K. 1.00Slightly better than glasses.
RTMC P.L. 1.00Wow, look at that. I'll be damned.
TSP J.S. 1.00About equal to eyeglasses.
CSSP M.S. 1.00Maybe better than glasses.
CSSP J.L. 1.25Definitely see a difference.
TSP S.P. 1.25Better than eyeglasses.
CSSP P.R. 1.25Fantastic.
TSP G.S. 1.25Better than glasses.
TSP E.B. 1.50/1.00 O' my word, marvelous.
CSSP S.D. 1.50/2.50 Just as good as glasses.
CSSP J.B. 1.50Incredible difference.
RTMC D.C. 1.50Close or equal to eyeglasses.
RTMC E.E. 1.50Makes a difference.
TSP P.F. 1.50Not better than glasses.
CSSP D.G. 1.50Better than with glasses.
TSP J.K. 1.50Huge improvement, incredible.
TSP G.M. 1.50Good grief, phenomenal, vastly better than eyeglasses, marvelous.
RTMC K.M. 1.50O' my god, I'll be darned.
RTMC S.M. 1.50Dandy.
CSSP P.P. 1.50Better than glasses.
TSP A.S. 1.50Same or better than glasses.
TSP R.T. 1.50Worked fine.
TSP D.G. 1.75Very slightly better than glasses.
RTMC L.K. 1.75Difference is amazing.
RTMC J.P. 1.75Oh My Gosh.
RTMC H.S. 1.75A little better.
RTMC D.L. 2.00Amazing, sharper than my glasses.
CSSP P.L. 2.00O' my God, that's the best view I've ever had through my left eye. Good Lord, right on, Holy Hannah. That's the real deal, incredible, Wow, I'm amazed.
TSP P.E. 2.25Better with DIOPTRX™.
TSP D.F. 2.50A little sharper than eyeglasses.
RTMC J.F. 2.50Bloody Fantastic.
TSP F.H. 2.50Much better than prescription.
CSSP T.L. 2.50Amazing.
RTMC J.S. 2.50Really sharp.
Unsolicited Owner Letters
Some correctors mentioned may be discontinued and others added since this was compiled.

Dear Mr. Nagler,

I am writing to praise your DIOPTRX, which has changed my astronomical life. You may recall that I was the first one you assessed at RTMC and I replied, when I looked through the 2.5 diopter version, "Bloody Fantastic!"

I immediately ordered one and I used it this past weekend at 7,500 feet elevation, under beautiful dark skies in northern Arizona (I have a Panoptic 27mm, a Radian 18mm a Radian 12mm and an 8" SCT).

To me the great advantage is the ability to see the entire field of view through an eyepiece. That is simply marvelous. I spent hours this weekend viewing nebulae, star fields, etc., in a manner of enjoyment I have never had. As my wife said, given the odd occasion when she has glanced through my telescope with her glasses on (she does not wear them for viewing normally), she always pitied me and other glasses wearers who had to view with such restricted fields of view, even with the longer eye relief eyepieces.

By coincidence, I had my annual visit to my optometrist yesterday, and we discussed their use. I actually would need a 3.0 diopter for my right eye and 2.75 for my astigmatic left eye, but he suggested I stay with the 2.5, as higher diopters (via stacking) would introduce possible unnecessary aberrations, and the 2.5 works well for me. The net result is that I ordered a second 2.5 DIOPTRX for use with my bino viewer (I have a pair of Radian 18s), which now will get much more use.

A sincere thank you for bringing it to market.

— Jim Fitzpatrick
Scottsdale, AZ

Dear Mr. Nagler,

The DIOPTRX 1.25 gave me excellent results with my 41 Panoptic, 31 Nagler, 26 Nagler and 18 Radian. I used the DIOPTRX in several different scopes I own (20 inch Starmaster f4.3, AP Traveler f6, and AP 178 f9.) I found improvements in star images and the appearance of Jupiter's moons in every scope/eyepiece combination producing an exit pupil greater than or equal to 3mm. I did not find that I needed more or less correction as the exit pupil became smaller or larger.

It is obvious that you truly care about the amateur astronomer and strive at every opportunity to enhance the experience of visual astronomy.

— Kim D. Colter, MD
Washington, MO

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