High index lenses for low/moderate Rx?

I'm wonderng if it is at all typical for people to prefer high index
lenses for vision quality, as opposed to just for cosmetic reasons or
to keep things lighter. My rx is not high, but I think I'm finding
that I much prefer the high index. I have two pairs of glasses with
the same Rx, one in regular plastic and the other in aspheric high
index (1.67 I think). I feel like I'm in a fish bowl in the regular
ones, plus stuff turns blurry if I look to far off to the side. The
high index ones are much better. Does that make sense or could it be
something else?

I had some Izon glasses that I liked too, and I was thinking that the
reason why was not because of the fancy wavefront stuff, but simply
because all the high index aspheric stuff came on them by default.

--

"Chuck" <(E-Mail Removed)> wrote in message
news:QkJEn.22$(E-Mail Removed)...
> I'm wonderng if it is at all typical for people to prefer high index
> lenses for vision quality, as opposed to just for cosmetic reasons or
> to keep things lighter. My rx is not high, but I think I'm finding
> that I much prefer the high index. I have two pairs of glasses with
> the same Rx, one in regular plastic and the other in aspheric high
> index (1.67 I think). I feel like I'm in a fish bowl in the regular
> ones, plus stuff turns blurry if I look to far off to the side. The
> high index ones are much better. Does that make sense or could it be
> something else?
>
> I had some Izon glasses that I liked too, and I was thinking that the
> reason why was not because of the fancy wavefront stuff, but simply
> because all the high index aspheric stuff came on them by default.

Usually it is the opposite. The higher the index, more chromatic aberration
(specified as abbe value, the higher the better) usually occurs. The
exception is polycarb which has the lowest abbe value of any commonly
prescribed material, but is only 1.59 index. Are you sure you have regular
plastic and not polycarb?

One explanation may be that if your vision has adapted to your 1.67 lens,
the regular plastic 1.50 lens may appear distorted because you are used to
the distortions of the 1.67 lens (especially those caused by an aspheric
design).

The regular plastic lens may not be the correct Rx any more, especially with
regard to cylinder/axis correction (for astigmatism). Are you sure the Rx's
are identical on both lenses? Also, both lenses may have been ordered with
the same exact Rx, but there may have been an error in the regular plastic
lens when it was made. It is also possible that the 1.67 lens was fit better
by the optician (closer to your eyes and properly centered), although most
regular plastic 1.50 lenses are spherical and not as sensitive to lens
fitting as aspherical designs.

Are you lenses single vision or progressive? If they are progressive, the
high index lens may have a more sophisticated progressive design than the
regular plastic one.

Mark A wrote:

> "Chuck" <(E-Mail Removed)> wrote in message
> news:QkJEn.22$(E-Mail Removed)...
> > I'm wonderng if it is at all typical for people to prefer high index
> > lenses for vision quality, as opposed to just for cosmetic reasons
> > or to keep things lighter. My rx is not high, but I think I'm
> > finding that I much prefer the high index. I have two pairs of
> > glasses with the same Rx, one in regular plastic and the other in
> > aspheric high index (1.67 I think). I feel like I'm in a fish bowl
> > in the regular ones, plus stuff turns blurry if I look to far off
> > to the side. The high index ones are much better. Does that make
> > sense or could it be something else?
> >
> > I had some Izon glasses that I liked too, and I was thinking that
> > the reason why was not because of the fancy wavefront stuff, but
> > simply because all the high index aspheric stuff came on them by
> > default.
>
> Usually it is the opposite. The higher the index, more chromatic
> aberration (specified as abbe value, the higher the better) usually
> occurs. The exception is polycarb which has the lowest abbe value of
> any commonly prescribed material, but is only 1.59 index. Are you
> sure you have regular plastic and not polycarb?
>
> One explanation may be that if your vision has adapted to your 1.67
> lens, the regular plastic 1.50 lens may appear distorted because you
> are used to the distortions of the 1.67 lens (especially those caused
> by an aspheric design).
>
> The regular plastic lens may not be the correct Rx any more,
> especially with regard to cylinder/axis correction (for astigmatism).
> Are you sure the Rx's are identical on both lenses? Also, both lenses
> may have been ordered with the same exact Rx, but there may have been
> an error in the regular plastic lens when it was made. It is also
> possible that the 1.67 lens was fit better by the optician (closer to
> your eyes and properly centered), although most regular plastic 1.50
> lenses are spherical and not as sensitive to lens fitting as
> aspherical designs.
>
> Are you lenses single vision or progressive? If they are progressive,
> the high index lens may have a more sophisticated progressive design
> than the regular plastic one.

I have single vision lenses. The ones that are giving me trouble are
transition lenses and are not poly. The distortion I'm having the most
trouble with is not like a chromatic abberation, but where the shape of
things varies significantly depending on angle. For example, if I look
at an object and move my head up and down while keeping my eyes on it,
the object appears to get taller and shorter. I don't have this (enough
to notice) in the high index. As I mentioned in the first post, the
ones I don't like also "defocus" when I look off center too far.

The order of events was that I got my new Rx from the doc and order
some glasses. When I got them I could not stand them due to distorted
fish bowl sensation. We tried a slightly lower power in one eye
thinking that it was to do with the fact that the differential power
between eyes had changed by 0.5D. This did not help. I decided to
order a trial of cheap glasses on-line with 0.25D less astigmatism
power in both eyes and also got 1.67 while I was at it. I liked these
right away, so went back to the eye doc and requested 0.25 less astig
power. When they came back they still seemed weird and distorting
(though better). I asked right away for the optician to read the new
ones and the cheapies from on-line and they were within 0.12 on all
measures.

I'm coming from the Izons which I believe are high index aspheric
automatically. Thing is, when I got those I liked them right away and
didn't have to "adapt". I have almost never in my life had any success
with just "giving it a week to adapt". If I hate them when I put them
on at the office, it almost never works.

--

Mike Tyner wrote:

>
> "Chuck" <(E-Mail Removed)> wrote
>
>
> > I have single vision lenses. The ones that are giving me trouble
> > are transition lenses and are not poly. The distortion I'm having
> > the most trouble with is not like a chromatic abberation, but where
> > the shape of things varies significantly depending on angle. For
> > example, if I look at an object and move my head up and down while
> > keeping my eyes on it, the object appears to get taller and
> > shorter. I don't have this (enough to notice) in the high index.
> > As I mentioned in the first post, the ones I don't like also
> > "defocus" when I look off center too far.
>
> I think the purpose of "aspheric" designs is to reduce off-axis
> distortion and blur.
>
> > The order of events was that I got my new Rx from the doc and order
> > some glasses. When I got them I could not stand them due to
> > distorted fish bowl sensation. We tried a slightly lower power in
> > one eye thinking that it was to do with the fact that the
> > differential power between eyes had changed by 0.5D. This did not
> > help.
>
> "Barrel" is the technical term for your "fishbowl." It's a function
> of power and index, but also other things. Base curve, vertex
> distance, center thickness, tilt and decentration can create big
> differences from one pair of frames to another.
>
> > I'm coming from the Izons which I believe are high index aspheric
> > automatically. Thing is, when I got those I liked them right away
> > and didn't have to "adapt". I have almost never in my life had any
> > success with just "giving it a week to adapt". If I hate them when
> > I put them on at the office, it almost never works.
>
> Spherical surfaces don't make ideal lenses, but it wasn't until the
> 70s and 80s that aspheric designs made it in spectacle lenses.
>
> Eyes come in a variety of aspheric shapes, and some like aspheric
> glasses, others don't care. It seems to work for you.
>
> Contact lenses reduce these distortions to zero, but you might not
> like that, if you're a "non-adapter".
>
> -MT

Thanks for the input. Sounds like I can attribute the difference to
the aspheric lenses then.

I did wear RGP contacts for about about a year and I loved my vision in
them. The drawbacks were dry eyes, limited wear time, discomfort in
wind and dust, "too big pupil" effects at night, etc. I may go back
though because, as you say, all the distortion stuff I hate about
glasses just disappears.

--

On May 9, 2:22*pm, "Chuck" <nos...@nospam.com> wrote:
> Mike Tyner wrote:
>
> > "Chuck" <nos...@nospam.com> wrote
>
> > > I have single vision lenses. *The ones that are giving me trouble
> > > are transition lenses and are not poly. *The distortion I'm having
> > > the most trouble with is not like a chromatic abberation, but where
> > > the shape of things varies significantly depending on angle. *For
> > > example, if I look at an object and move my head up and down while
> > > keeping my eyes on it, the object appears to get taller and
> > > shorter. I don't have this (enough to notice) in the high index.
> > > As I mentioned in the first post, the ones I don't like also
> > > "defocus" when I look off center too far.
>
> > I think the purpose of *"aspheric" designs is to reduce off-axis
> > distortion and blur.
>
> > > The order of events was that I got my new Rx from the doc and order
> > > some glasses. *When I got them I could not stand them due to
> > > distorted fish bowl sensation. *We tried a slightly lower power in
> > > one eye thinking that it was to do with the fact that the
> > > differential power between eyes had changed by 0.5D. *This did not
> > > help.
>
> > "Barrel" is the technical term for your "fishbowl." It's a function
> > of power and index, but also other things. Base curve, vertex
> > distance, center thickness, tilt and decentration can create big
> > differences from one pair of frames to another.
>
> > > I'm coming from the Izons which I believe are high index aspheric
> > > automatically. *Thing is, when I got those I liked them right away
> > > and didn't have to "adapt". *I have almost never in my life had any
> > > success with just "giving it a week to adapt". *If I hate them when
> > > I put them on at the office, it almost never works.
>
> > Spherical surfaces don't make ideal lenses, but it wasn't until the
> > 70s and 80s that aspheric designs made it in spectacle lenses.
>
> > Eyes come in a variety of aspheric shapes, and some like aspheric
> > glasses, others don't care. It seems to work for you.
>
> > Contact lenses reduce these distortions to zero, but you might not
> > like that, if you're a "non-adapter".
>
> > -MT
>
> Thanks for the input. *Sounds like I can attribute the difference to
> the aspheric lenses then.
>
> I did wear RGP contacts for about about a year and I loved my vision in
> them. *The drawbacks were dry eyes, limited wear time, discomfort in
> wind and dust, "too big pupil" effects at night, etc. *I may go back
> though because, as you say, all the distortion stuff I hate about
> glasses just disappears.
>
> --

There's a Brave New World in contact lens technologies.

It may BE worth another try.

Depending on how bad the dry eye issue is/was ... things like lower
punctal plugs, flax seed oil, or a decent (and preservative-free)
lubricating drop may make your experience relatively pain-free.