Televue Dioptrx

[bomberbaz]

Ok think I have mentioned about this before but tonight I have spent time doing nothing other than testing this out on stars clusters and doubles and results are excellent so I thought I would post a brief review.

For any astigmatism afflicted viewers like me these adaptors are a godsend. They correct the abnormal shape in our eyes, doing away the need to wear your specs and open up a whole new world as far as viewing is concerned. I went this way because it is cheaper than paying £4000-£5000 for surgery to correct this, That said my collection in my sig below goes a fair way to getting there 

Back to the results. After much turning and twisting of the Dioptrx to find the absolute perfect position which in my case is between A and B marked on the rim at 12 o'clock, I went on a tour of various clusters, a few doubles and then just panned around the sky looking at constellations. This is for me, a glasses wearer such a revelation, liberating even. To be able to see stars as pinpoints of light accross most of the FOV rather than seagulls due to the shape of my glasses lens was just brilliant. Especially using the Nikons and actually getting to drink in all that fantastic FOV that comes with this EP. 

They also fit a few other EP's that are available much cheaper so you don't have to spend a small fortune like I did if you want to take advantage of this wonderful adaption from televue. Vixen LVW are one make but I believe it is the size of the top of the eyepiece without a guard on it.

Anyway, finalkly I have nailed using these and I am looking forward to SGL12 for some great deep sky viewing.

Steve

[Singlin]

Sounds great.

Is their a list of compatible eyepieces?

[bomberbaz]

Hopefully one of our American cousins can enlighten us more on that because I am not sure. 

[Uplooker]

Hi Steve,

Congrats on getting great results. I did not contribute to your thread on this but I did follow it. I do have astigmatism, but thankfully not severe enough to affect my viewing. Glad you have gotten a solution

[Saganite]

Hi Steve,

that is good news and I am pleased for you. A recent eye test has revealed that I have astigmatism so I think it will not be long before I try the Dioptrx also.

[Charic]

Is your astigmatism equal for both eyes, meaning only one Dioptrx is required? I can use either eye ( requires different dioptre ) but buying the correct dioptre to match the dominant eye should suffice, after all, they wont be give-away prices!
My  first Delos was just to compare with a BST and in the hope of gaining a new and bigger scope  / faster scope?  yet one of their attributes is, as you mention, their astigmatism corrector, " better than glasses" they say ? This could be a game changer for me, as I don't like to wear glasses at the scope, just too much space, I like to bury the eye into the eyepiece! But wearing glasses alone and looking up, I see clearer, so it goes to assume, I should learn to use my prescriptions at the eyepiece, especially as the Delos caters for it with 20mm eye-relief, or just get a Dioptrx corrector and bury the eye into the raised eye-guard.
 

[Charic]

2 hours ago, Singlin said:

Sounds great.

Is their a list of compatible eyepieces?

Some Info here.......... http://www.televue.com/engine/TV3b_page.asp?id=54&Tab=_Choose
 

[Louis D]

Anyone tried one with a 100 degree or wider eyepiece?  If so, when looking at the edge directly, does the Dioptrx introduce chromatic aberrations like looking through a pair of polycarbonate eyeglass lenses?  I have to be careful to try to keep my eyeglasses flat on my face even when it would be easier to flatten them against the top of the eyepiece to see the edge, or I will get nasty red/blue color separation.  It's a function of polycarbonate being a single element, high index optical material.

[bomberbaz]

1 hour ago, Louis D said:

Anyone tried one with a 100 degree or wider eyepiece?  If so, when looking at the edge directly, does the Dioptrx introduce chromatic aberrations like looking through a pair of polycarbonate eyeglass lenses?  I have to be careful to try to keep my eyeglasses flat on my face even when it would be easier to flatten them against the top of the eyepiece to see the edge, or I will get nasty red/blue color separation.  It's a function of polycarbonate being a single element, high index optical material.

I cant say I noticed any but maybe I should have tried something brighter to see, (the Nikon's have a 102 afov).  Next time out I will try looking at the moon and see how she stands up to with them. I have tried to find another report I read on here but cannot. However if memory serves me right from that report I don't think it will. I am not an optician of course but would have thought corecting the lightpath to one's own eye specifically would not cause CA. I may be wrong.

[bomberbaz]

Found an earlier review here by Keith.

 

[Louis D]

From the above linked review:

Then came the most important test. Would the Dioptrx work with my 102deg NAV-HW? When I observed with my glasses on, it produced an unacceptable amount of lateral colour near the edges. These colour were absent when I observed without my glasses, but stars become distorted by my astigmatism. My spectacles simply can’t cope with me viewing 50deg off axis and this was the reason why I ordered the Dioptrx.

I inserted the Dioptrx, pressed my eye socket against the rubber eye guard and let the Pleiades drift. The stars were pin point up to the field stop.

That seems to answer my question.  I can get pinpoint stars way off axis, but it requires keeping my glasses flush to my face and looking through the center of them by tipping my head off axis rather than rotating my eye in its socket.  Of course this means I lose the entire rest of the view, so not very satisfying.  Thanks for finding that boberbaz.

[Charic]

Steve.  do you find one Dioptrx  sufficient, having more than one eyepiece, or is it as quick as say, screwing a Barlow lens onto an EP, when transferring the Dioptrx to another eyepiece?

[bomberbaz]

12 hours ago, Charic said:

Steve.  do you find one Dioptrx  sufficient, having more than one eyepiece, or is it as quick as say, screwing a Barlow lens onto an EP, when transferring the Dioptrx to another eyepiece?

Its simple mate, a quick twist takes it off and the same in reverse to get it back on, much quicker than screwing a barlow, filter etc. You need to remember to rotate the dioptrx to your eye position though, so I have marked the rim of mine with a drop of liquid paper to make it stand out easier. 

Other than that, its very simple and much more satisfying than glasses, trust me.