Best Zeiss Lens For Rx Eyeglasses
Kenneth Berg
Previous thread convinced me to buy Zeiss lenses. Checking my
Optometrist's catalog I see the following glass single vision lenses
available from Zeiss:
Lantal 1.8
Lantal 1.9
Punktal 1.6
TITAL 1.7
Each available with Super ET and Gold ET AR coatings.
My particular prescription is:
OD -0.75 -2.00 x 080
OS -1.00 -1.25 x 100
ADD +2.50 PAL
I checked, and this prescription is for optimal vision, not undercorrected.
Can someone help explain which of the lenses I should get?
Kenneth Berg
the Lantal lenses for anyone requiring less than a 4 diopter correction.
There is a metric for image correctness that they told me about (I forgot
what it is
called), and the Punktal 1.6 was rated about 10% better than the TITAL 1.7.
This is consistent with what my Optometrist said that you give up image
quality with higher index glass. Zeiss also told me that there were a few
more
coatings applied of the Super ET AR than the Gold ET AR. This is not
intended
to affect the optics, but is necessary to obtain the color that they wanted.
Kenneth Berg wrote in message ...
William Schneider
first pair of glasses, mostly for close focus. My prescription is not strong
and is mostly to accomodate the effects of aging eyes.
I have the 1.6 index glass, a varifocal grind instead of bifocals, and I
requested the SuperET antireflections instead of the gold. I also purchased
smaller frames thinking that smaller lenses could be fitted closer to the
eye to minimize eye relief loss.
I find that the AR coating is the best part of these glasses, and even night
time driving doesn't produce objectionable flare. While not called gold, it
has a subtle goldish tint instead of the green or magenta tint that most
camera lenses have. I would rate its effectiveness high for suppressing
reflections .
However I am dissapointed at how my prescription works at distance in dim
light. Venus is not a point of light through the glasses like I see it
without them. I suspect that the Opthomologist didn't listen to my request
for glasses that would work effectively at infinity focus. Or maybe that's
just the way glasses are.
Worse (and this may be a characteristic of all eyeglasses), there is some
color on high contrast objects. The red and blue fringing that we all
discuss here appears with these eyeglasses. It limits the fineness of detail
that can be resolved. I mentioned it to the optician, and he said that no
one elses had complained about this effect. Has anyone else noticed this
with their glasses?
The cost of the Zeiss lenses was high. I spent $587 for this pair of glasses
(insurance paid a whopping $75 of this total). If they worked better, I
would feel that the money was well spent, but they now serve mostly as
expensive reading glasses.
Tim Khan
schn...@oak.cats.ohiou.edu> wrote:
>However I am dissapointed at how my prescription works at distance in dim
>light. Venus is not a point of light through the glasses like I see it
>without them. I suspect that the Opthomologist didn't listen to my request
>for glasses that would work effectively at infinity focus. Or maybe that's
>just the way glasses are.
>
I also have the Zeiss lenses, and the same distance seeing problem. I
went back to the ophthalmologist and asked to push the prescription a
diopter, this greatly improved distant observing. On clear and steady
nights I can count 9 to 10 stars in the Pladies. If you do so, make
sure that your vision works up close.
Tim
Dave Storey
<schn...@oak.cats.ohiou.edu> writes
>I recently purchased some Zeiss lenses after reading posts here. This is my
>first pair of glasses, mostly for close focus. My prescription is not strong
>and is mostly to accomodate the effects of aging eyes.
>
>However I am dissapointed at how my prescription works at distance in dim
>light. Venus is not a point of light through the glasses like I see it
>without them. I suspect that the Opthomologist didn't listen to my request
>for glasses that would work effectively at infinity focus. Or maybe that's
>just the way glasses are.
Two suggestions .. 1) In dim light your pupils open up, which typically
makes any 'poor eyesight' problems worse, since aberrations in the
outside part of the cornea are usually worse, &/or 2) Did the suckers
actually make the lenses right? I have had eyeglasses back that were 1/2
diopter off what the prescription called for (and in one case, the axis
of the cylindrical component 50 degrees off, since my optician's '185'
got read as '135' .. damn man wrote worse than a doctor).
>
>Worse (and this may be a characteristic of all eyeglasses), there is some
>color on high contrast objects. The red and blue fringing that we all
>discuss here appears with these eyeglasses. It limits the fineness of detail
>that can be resolved. I mentioned it to the optician, and he said that no
>one elses had complained about this effect. Has anyone else noticed this
>with their glasses?
No, my cheapo plastic lenses (non zeiss) show no chromatic aberrations
at all. Those are coated varilux lenses, which reminds me, time I went
and got retested ..
>
>The cost of the Zeiss lenses was high. I spent $587 for this pair of glasses
>(insurance paid a whopping $75 of this total). If they worked better, I
>would feel that the money was well spent, but they now serve mostly as
>expensive reading glasses.
If you aren't happy with them, take them back and complain louder. Worst
they can do is say 'tough luck', which will help your decision next time
you are buying. You might also ask him to test your eyes under the sort
of low light conditions you are having trouble with (if he didn't
already).
Rgds
Dave Storey
Mike_Stebbins
Dave,
I, like you have had no problems with plastic lenses, I had found that
Zeiss lenses outperformed polycarb by a wide margin in clarity and
duribility. My lenses were $80 per side, I had my own frames.
Glasses made for close reading by definition are not designed for
focusing at infinity, this can be adjusted out at the focuser.
The out of focus problem is probably not with the construction of the
lenses. It is more likely a problem with the perscription. Most
perscriptions are written for uncorrection, becuase 'most' people will not
find fault with undercorrection, an easy test is to push lenses much closer
to your face than normal, if you see more clearly the lenses are
undercorrected (or so I am told). You really have to demand a 'correct'
perscription, I've asked nicely and still gotten 'the usual'. I understand
they really have to measure the distance from your eye to the lens to get
this right (how many times has anyone done that for you?) After sending
polycarb lenses back 5 (five) times the lens maker refused to try again,
citing ANSI standards. I switched to Zeiss and they were made correctly the
first time, although with an undercorrected perscription, sometimes you
can't win.
Mike Stebbins
reply to nhas at compuserve dot com
Jim Van Nuland
>Date: Wed, 14 Apr 1999 19:05:46 GMT
>On Wed, 14 Apr 1999 13:08:45 GMT, "William Schneider" <
>schn...@oak.cats.ohiou.edu> wrote:
>>However I am disappointed at how my prescription works at distance in dim
>>light. Venus is not a point of light through the glasses like I see it
>>without them. I suspect that the Ophthalmologist didn't listen to my request
>>for glasses that would work effectively at infinity focus. Or maybe that's
>>just the way glasses are.
Not so! Your Optho didn't pay attention. But see below.
>I also have the Zeiss lenses, and the same distance seeing problem. I
>went back to the ophthalmologist and asked to push the prescription a
>diopter, this greatly improved distant observing. On clear and steady
>nights I can count 9 to 10 stars in the Pleiades. If you do so, make
>sure that your vision works up close.
This is why bi- and tri-focals were invented! I can see pinpoint
stars, and have good reading focus, with no compromise. For in-between,
the top D-segment is intermediate. And no stray color. I don't know
what plastic they are made of; the only coating is scratch-resistance.
And they cost $200 US, insurance paid it.
* SLMR 2.1a * Some days it's not worth chewing through the restraints.
__
| Internet: Jim.Van...@sjpc.org
| Fidonet: Jim Van Nuland 1:143/11
|
| A service of the San Jose IBM PC Club, running OS/2 Warp
William Hamblen
<Mike_S...@email.msn.com> wrote:
>... I understand
>they really have to measure the distance from your eye to the lens to get
>this right (how many times has anyone done that for you?)
I believe spectacle lenses are supposed to be mounted so the center of
curvature of the surface nearer the eye is located at roughly the
center of the eyeball so the distance from your natural lens to the
spectacle lens doesn't change much when you look in different
directions.
William Hamblen
schn...@oak.cats.ohiou.edu> wrote:
>Worse (and this may be a characteristic of all eyeglasses), there is some
>color on high contrast objects. The red and blue fringing that we all
>discuss here appears with these eyeglasses. It limits the fineness of detail
>that can be resolved. I mentioned it to the optician, and he said that no
>one elses had complained about this effect. Has anyone else noticed this
>with their glasses?
Eyeglasses are simple lenses and therefore have chromatic aberration.
The human eye is not achromatic either. Obviously the higher the
power in your prescription the more noticeable chromatic aberration
will be. I've noticed the effect with my glasses.
William Schneider
lenses? I imagine that research has been done on the topic, but I assume the
cost/benefit ratio prevents them from being accepted in the marketplace.
Mark
The following comment from the optician is a lie or he has only
dispenced glasses to 5 people in his life. &^%$# ignorant slacker jerkoff.
>Worse (and this may be a characteristic of all eyeglasses), there is some
>color on high contrast objects. The red and blue fringing that we all
>discuss here appears with these eyeglasses. It limits the fineness of
detail
>that can be resolved.
Part that pisses me off!!!!!!
I mentioned it to the optician, and he said that no
>one elses had complained about this effect. Has anyone else noticed this
>with their glasses?
Of coarse lots of people have!
Eyewear needs to be measured/made/ and fitted by an expierienced
optician. Zeiss is making ultra high index lenses. All high index lens
( Ziess or not ) have built in distortion. Due to the front curve of the
lens and in some cases the material it's made from. The perifery of the
lens where it is easiest to see for the following reasons.
There is also a need to adjust glasses to your head before measuring
from the bottom of the lens to the center of your pupil called the Optical
Center. The farther from the pupil center the O. C. is the more the
distortion is noticed. Also, it goes without saying that your option is
measuring your Pupilary Distance or ( P.D.).
Plus the "normal" Dr's Refraction Exam is set at 14mm from your cornia.
Final frame adjustments can move this in too close or too far off your
face. Affecting how you see.
I have a pair of anti-reflective, crown glass lenses with NO tinting. I
use these at the elescope. I also have a pair of A/R coated Spectralite
H.I. plastic lens that I live in. they are the best that I'm aware of from
Sola Optical. They have the relative safety of plastic and are as
comfortable to see with as CR-39.
Glass is and as far as technology/ lens materials is today will always
be the clearest choice over CR-39 plastic, and most certainly much better
visually ( to the trained eye) than any high index form of plastic, and
lastly Polycarbanate is the least clear lens to wear. Though it is the
safest and the lightest I hated the way I saw with it.
Finally, there is only so much a Dr. or optician can do regarding
correcting vision in the non-ematropic eye. Or, in other words the more
diopters of power equals more thickness in the lenses. I can make a non
corrective lens 8mm thick ( with any material ) and you will have edge
thickness and some
Chromatic Distortion when you view it. Keep the frame as small as you can
tolerate and you will minamize edge thickness and distortion in most cases.
These are just a few things of a host of frame adjustments/eye
conditions/ frame choices/ lens choices/ not to mention phycological
conditians a GOOD Optician looks for and educates his customer with.
I'd also advise you to find a new optician,. If you are the !rst time
he's heard about Chromatic Aborations from a H.I. lens....he's either
lieing to you or is a total #@%^$ slacker. Ask to see his Licience, if he
even has one! If he does buy him a book on basic optics and give it to him.
I'd have to resist the urge to throw it at him.
Remember astronomers are self trained to see subtle details. So you may
see them with your glasses and because of your glasses. so If you are able
take your glasses off when you observe. I unfortunitly don't have that
option as do many others. So I use glass NOT H.I. glass.
Mark A.B.O.C.
P. S. Lenscrafters garentees your complete satisfaction for 1 month for ANY
reason!
P.P.S. Thanks for Reading this. I leave my soap box now.
<snip>