Astigmatism Correction Eyepieces
Posted 29 June 2005 - 09:19 PM
Dioptrx Astigmatism Correctors
I currently am wearing progressive eyeglasses and am frustrated.
Will these things screw onto any EP or just Tele-Vue's ?
Of course.........I would have to buy 2 of them.....
Posted 29 June 2005 - 10:29 PM
I don't have any experience with the dioptrx correctors.
You're asking for problems using progressive lenses. They are great for everyday use but may be problematic in astronomy. Unlike standard bifocals the differant zones on a progressive lens are very hard to define. Their strength is their weakness. With the smooth transition between the distance and reading segments you have a differant Rx in almost every location. It's hard to tell where the distance Rx begins and ends. Not only does the Rx change from distance to near, but there are areas in progressive lenses which are not clear at any distance. Again this is the consequence of a "no line" bifocal.
If you want to define the distance zone you have to locate a small (very small ~ 0.5mm) etched circle or symbol on the lens. The area above an imaginary horizontal line which passes through this point should (emphasis on should) be the equivalent of a simple distance Rx. These etched markings are usually about 1/4 to 1/3 in from the lateral edge of the lens. They are hard to see unless you hold them just right.
For astronomy use I would try a simple distance Rx or have the shop place the near segment lower down in the frame. This would make it less likly to interfere at the eyepiece.
Another idea is to try contact lenses. There are soft lenses which also correct astigmatism. Hard lenses, while not as popular, do a fabulous job of correcting astigmatism. Contact lenses would solve eye relief problems and a pair of 1$ reading glasses would work over the lenses if needed for near vision.
I won't even start (well maybe a little) with refractive surgery. But an up-coming issue of S&T will have an article about LASIK and the astronomer. I have no idea if the story is pro/con/neutral about the surgery.
Posted 30 June 2005 - 05:01 AM
Posted 30 June 2005 - 05:28 PM
I didn't mean to come down so hard against progressive lenses. I'm sure many people (including you) use them without any problems while observing.
While Gary mentions his progressive specs, his frustration my be related to some other issue. He should have them checked by the shop that made them and the person that prescribed them.
As to his initial question, does anyone out there have info on the Dioptrx correctors?
Posted 30 June 2005 - 05:51 PM
Posted 30 June 2005 - 07:08 PM
Posted 30 June 2005 - 08:52 PM
Apparently the Sept. 2005 issue of Astronomy will have a review of the Dioptrx correctors.
Posted 01 July 2005 - 11:11 AM
just noticed that the S&T issue that will have the LASIK article will also have an article about what type of eyeglasses work well with telescopes and binos. They will also be reviewing an unspecified giant bino (maybe bino-telescope) in the same issue.
Posted 01 July 2005 - 01:14 PM
Posted 01 July 2005 - 06:28 PM
Posted 04 July 2005 - 09:09 AM
My frustrations with my eyes have been an ongoing battle. There are much worse eyes out there but I am very criticle with focus. I have been into photography for about 40 years and have always demanded "tack". When I look up and see fuzzy stars I just feel sick about it.
Close focus in the last 3 pairs of progressives is a test. It seems as though I have one eye in focus at a time...closing that eye and moving my head a very little bit brings the other eye in focus. When I present this to the Opto-Doc....they check for that small symbol your refering too......check my IPD..........and confirm for themselves that everything is perfect. Ive been thru many many glasses and about 4 eye docs in the last 10 years. At this point Ive almost just given up. One of the Docs told me that I cant expect to have perfect, sharp vision. I have talked to several of his customers and he tells everyone the same thing.
I have always wanted to design and manually adjust my lenses manually "on the fly" so to speak for the task at hand. I really think that this will be an option in the future of optometry. If I want 2x.....dial it in.....close vision.................dial it in. "I" should be responsible for how sharp my vision is. An examination "X" amount of months ago during an office call on a late Friday afternoon................just doesnt seem the right way to go.
Speaking of which...............my eyeballs are 49 years old. They are changing and have been changing for about 15 years. I have noticed these changes in increments. I have noticed changes in my vision while Im sick.........than ....after I get better my vision would improve....but not where it was before the sickness. Im not talking a great degree here....just a very small bit, but...they add up. Then when its time for a new examination...low and behold my script has changed enough for some more correction.
I feel I can rant to you guys about this because I feel that most of you are as criticle about focus as I am. I know when something is not in focus......and I have to rely on technology to correct it. Opto technology is improving. I predict......one day....I will be able to focus my own glasses...just as I turn the IF EP's on my Bt's.
ps........I appreciate vision.......I am happy I can see at all. Its a gift.
Posted 04 July 2005 - 09:58 AM
The same type that the Doc himself is using.!
Posted 05 July 2005 - 01:58 PM
this give me a solution.
I am in the process to made a binocular whit photocopier lens and add astigmatism correction in the parth of the light before the final occular whit one of my old glass
note I have a 750 dioptri corrector at 20 degree that mean I do see any thing in ordinary binocular the televue stop at 2.5 normal only some animal like me have 750
I try this :put my old glass after the occular and tel you if it work or if it is better to put before.
but maybe you can used and old glass whitout reading or progressive correction and try it simple solution.
jacques savard 47'N 71'O