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| Author |
Message |
John Phillips
medicine forum beginner
Joined: 08 Jul 2006
Posts: 4
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 Posted: Sat Jul 08, 2006 6:05 pm Post subject:
Selecting lenses
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I would be grateful if anyone could offer some advice on selecting
single-vision lenses for a drilled rimless frame.
Prescription:
SPH CYL AXIS PRISM BASE VIA
R -2.25 -0.50 52.5 - - 6/6
L -2.00 - - 6/6
Add R +2.00
L +2.00
PD is 68 mm
I have worn Zeiss CR-39 lenses (no other details, I'm afraid) to a
very slightly different former prescripton for many years with complete
comfort.
A new optician (I moved) tested me and ordered me some 1.6 index lenses
from Shamir for some new rimless frames (Lindberg Spirit) and I have
been getting used to them for three weeks.
The new prescription (above) is fine on-axis.
I can tolerate the much increased off-axis chromatic distortion.
However the off-axis barrel distortion is too much. I no longer feel
nausea, but after three weeks I still feel far too uncomfortable in
confined spaces such as the aisles at the supermarket. I suspect it
will not get much better with more time.
The old Zeiss lenses showed very little of either distortion. But the new
frames do need a 1.6 (or greater) index lens so CR-39 is apparently out.
Is there some specific lens product I can ask for which will minimize
the barrel distortion in a 1.6 index lens?
I know some barrel distortion off-axis is normal but does it always get
so much worse with 1.6 index lens material?
I took advice from an independent optician and he suggested Hoya 1.6 Eyas.
He said (if I understand correctly) that although the Eyas lens geometry
did not specifically deal with barrel distortion he thought it would
at least minimize it to the point of being no worse than the old Zeiss
lenses. Does this sound right?
I also understand the Hoya 1.6 Eyas has a good ABBE value so it will
minimize the off-axis chromatic aberration (even if this is not a big
issue for me).
Any advice will be received gratefully. My priority is the performance
of the lens, coming well above aesthetics.
--
John Phillips |
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Anon E. Muss
medicine forum Guru Wannabe
Joined: 22 May 2006
Posts: 136
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| Posted: Sat Jul 08, 2006 11:33 pm Post subject:
Re: Selecting lenses
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On 08 Jul 2006 18:05:34 GMT, John Phillips
<news0309@DontUseThis.mainly.me.uk> wrote:
| Quote: | I would be grateful if anyone could offer some advice on selecting
single-vision lenses for a drilled rimless frame.
Prescription:
SPH CYL AXIS PRISM BASE VIA
R -2.25 -0.50 52.5 - - 6/6
L -2.00 - - 6/6
Add R +2.00
L +2.00
PD is 68 mm
I have worn Zeiss CR-39 lenses (no other details, I'm afraid) to a
very slightly different former prescripton for many years with complete
comfort.
A new optician (I moved) tested me and ordered me some 1.6 index lenses
from Shamir for some new rimless frames (Lindberg Spirit) and I have
been getting used to them for three weeks.
The new prescription (above) is fine on-axis.
I can tolerate the much increased off-axis chromatic distortion.
However the off-axis barrel distortion is too much. I no longer feel
nausea, but after three weeks I still feel far too uncomfortable in
confined spaces such as the aisles at the supermarket. I suspect it
will not get much better with more time.
The old Zeiss lenses showed very little of either distortion. But the new
frames do need a 1.6 (or greater) index lens so CR-39 is apparently out.
Is there some specific lens product I can ask for which will minimize
the barrel distortion in a 1.6 index lens?
|
For a drilled rimless frame, a lens made out of TRIVEX is the material
of choice in 07/2006.
I would try Hoya's Summit ECP progressive in TRIVEX. The distortion
in your 1.6 lenses may be due to the material or the lens design. It
is hard to tell, but that is what I would recommend.
[snip] |
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Mark A
medicine forum Guru Wannabe
Joined: 30 Apr 2005
Posts: 226
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| Posted: Sat Jul 08, 2006 11:52 pm Post subject:
Re: Selecting lenses
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"John Phillips" <news0309@DontUseThis.mainly.me.uk> wrote in message
news:slrneavsve.aie.news0309@linux.mainly.me.uk...
| Quote: | I would be grateful if anyone could offer some advice on selecting
single-vision lenses for a drilled rimless frame.
Prescription:
SPH CYL AXIS PRISM BASE VIA
R -2.25 -0.50 52.5 - - 6/6
L -2.00 - - 6/6
Add R +2.00
L +2.00
PD is 68 mm
I have worn Zeiss CR-39 lenses (no other details, I'm afraid) to a
very slightly different former prescripton for many years with complete
comfort.
A new optician (I moved) tested me and ordered me some 1.6 index lenses
from Shamir for some new rimless frames (Lindberg Spirit) and I have
been getting used to them for three weeks.
The new prescription (above) is fine on-axis.
I can tolerate the much increased off-axis chromatic distortion.
However the off-axis barrel distortion is too much. I no longer feel
nausea, but after three weeks I still feel far too uncomfortable in
confined spaces such as the aisles at the supermarket. I suspect it
will not get much better with more time.
The old Zeiss lenses showed very little of either distortion. But the new
frames do need a 1.6 (or greater) index lens so CR-39 is apparently out.
Is there some specific lens product I can ask for which will minimize
the barrel distortion in a 1.6 index lens?
I know some barrel distortion off-axis is normal but does it always get
so much worse with 1.6 index lens material?
I took advice from an independent optician and he suggested Hoya 1.6 Eyas.
He said (if I understand correctly) that although the Eyas lens geometry
did not specifically deal with barrel distortion he thought it would
at least minimize it to the point of being no worse than the old Zeiss
lenses. Does this sound right?
I also understand the Hoya 1.6 Eyas has a good ABBE value so it will
minimize the off-axis chromatic aberration (even if this is not a big
issue for me).
Any advice will be received gratefully. My priority is the performance
of the lens, coming well above aesthetics.
--
John Phillips
|
Your request say single-vision lenses, but your Rx includes an add power for
bi-focals or progressives. Do want lenses only for the distance vision, or
do you want progressives? |
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John Phillips
medicine forum beginner
Joined: 08 Jul 2006
Posts: 4
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| Posted: Sun Jul 09, 2006 2:41 am Post subject:
Re: Selecting lenses
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On 2006-07-08, Mark A <nobody@nowhere.com> wrote:
| Quote: | "John Phillips" <news0309@DontUseThis.mainly.me.uk> wrote in message
news:slrneavsve.aie.news0309@linux.mainly.me.uk...
I would be grateful if anyone could offer some advice on selecting
single-vision lenses for a drilled rimless frame.
Prescription:
SPH CYL AXIS PRISM BASE VIA
R -2.25 -0.50 52.5 - - 6/6
L -2.00 - - 6/6
Add R +2.00
L +2.00
PD is 68 mm
Your request say single-vision lenses, but your Rx includes an add power for
bi-focals or progressives. Do want lenses only for the distance vision, or
do you want progressives?
|
Sorry for the confusion. I just reproduced everything that was written
on the prescription card.
I definitely want single-vision lenses for distance vision so I suppose
the "Add" informtion is irrelevant.
--
John Phillips |
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John Phillips
medicine forum beginner
Joined: 08 Jul 2006
Posts: 4
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| Posted: Sun Jul 09, 2006 2:46 am Post subject:
Re: Selecting lenses
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On 2006-07-08, Anon E Muss <anonymous@example.org> wrote:
| Quote: | On 08 Jul 2006 18:05:34 GMT, John Phillips
news0309@DontUseThis.mainly.me.uk> wrote:
I would be grateful if anyone could offer some advice on selecting
single-vision lenses for a drilled rimless frame.
Prescription:
SPH CYL AXIS PRISM BASE VIA
R -2.25 -0.50 52.5 - - 6/6
L -2.00 - - 6/6
Add R +2.00
L +2.00
PD is 68 mm
I have worn Zeiss CR-39 lenses (no other details, I'm afraid) to a
very slightly different former prescripton for many years with complete
comfort.
...
Is there some specific lens product I can ask for which will minimize
the barrel distortion in a 1.6 index lens?
For a drilled rimless frame, a lens made out of TRIVEX is the material
of choice in 07/2006.
I would try Hoya's Summit ECP progressive in TRIVEX. The distortion
in your 1.6 lenses may be due to the material or the lens design. It
is hard to tell, but that is what I would recommend.
|
Thanks. I will push back and see if my optician will relent on the 1.6
index material and give me TRIVEX (1.53 I think).
However just to be clear I am not after progressive lenses - just single
vision for distance (sorry for the confusion - I just reproduced the
entire prescription card and I guess the "Add" bit is not relevant to
single vision lenses).
--
John Phillips |
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Mark A
medicine forum Guru Wannabe
Joined: 30 Apr 2005
Posts: 226
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| Posted: Sun Jul 09, 2006 3:01 am Post subject:
Re: Selecting lenses
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"John Phillips" <news0309@DontUseThis.mainly.me.uk> wrote in message
news:slrneb0rgs.aq4.news0309@linux.mainly.me.uk...
| Quote: | Thanks. I will push back and see if my optician will relent on the 1.6
index material and give me TRIVEX (1.53 I think).
However just to be clear I am not after progressive lenses - just single
vision for distance (sorry for the confusion - I just reproduced the
entire prescription card and I guess the "Add" bit is not relevant to
single vision lenses).
--
John Phillips
|
Another good mid-index lens in Sola Spectralite 1.54, or if you need a 1.6
lens then Sola Finalite.
If you want Trivex, both Hoya and Younger optical have SV lenses in this
material. |
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Anon E. Muss
medicine forum Guru Wannabe
Joined: 22 May 2006
Posts: 136
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| Posted: Sun Jul 09, 2006 6:01 am Post subject:
Re: Selecting lenses
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On 09 Jul 2006 02:46:52 GMT, John Phillips
<news0309@DontUseThis.mainly.me.uk> wrote:
| Quote: | On 2006-07-08, Anon E Muss <anonymous@example.org> wrote:
|
[snip]
| Quote: | For a drilled rimless frame, a lens made out of TRIVEX is the material
of choice in 07/2006.
|
[snip]
| Quote: | Thanks. I will push back and see if my optician will relent on the 1.6
index material and give me TRIVEX (1.53 I think).
|
I would get the Trilogy or Phoenix Aspheric TRIVEX SV lens and
recommend they try and match the front curves (as much as possible) of
your old Zeiss CR-39 lenses.
BTW, besides having slightly better optics than 1.6, TRIVEX is much
stronger and less likely to break in a rimless design. |
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Robert Martellaro
medicine forum Guru Wannabe
Joined: 03 May 2005
Posts: 187
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| Posted: Mon Jul 10, 2006 5:41 pm Post subject:
Re: Selecting lenses
|
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|
On 08 Jul 2006 18:05:34 GMT, John Phillips <news0309@DontUseThis.mainly.me.uk>
wrote:
| Quote: | I would be grateful if anyone could offer some advice on selecting
single-vision lenses for a drilled rimless frame.
Prescription:
SPH CYL AXIS PRISM BASE VIA
R -2.25 -0.50 52.5 - - 6/6
L -2.00 - - 6/6
Add R +2.00
L +2.00
PD is 68 mm
I have worn Zeiss CR-39 lenses (no other details, I'm afraid) to a
very slightly different former prescripton for many years with complete
comfort.
A new optician (I moved) tested me and ordered me some 1.6 index lenses
from Shamir for some new rimless frames (Lindberg Spirit) and I have
been getting used to them for three weeks.
The new prescription (above) is fine on-axis.
I can tolerate the much increased off-axis chromatic distortion.
However the off-axis barrel distortion is too much. I no longer feel
nausea, but after three weeks I still feel far too uncomfortable in
confined spaces such as the aisles at the supermarket. I suspect it
will not get much better with more time.
|
Blur, color, or both? Chroma should be imperceptible at this power. There may be
other problems that need correcting e.g. waves, warpage, incorrect lens
positioning.
| Quote: | The old Zeiss lenses showed very little of either distortion. But the new
frames do need a 1.6 (or greater) index lens so CR-39 is apparently out.
Is there some specific lens product I can ask for which will minimize
the barrel distortion in a 1.6 index lens?
|
Nope. Moving the lenses closer to the eyes will help. Contact lenses would help
the most.
| Quote: | I know some barrel distortion off-axis is normal but does it always get
so much worse with 1.6 index lens material?
|
It's not the lens material, it's the lens positioning.
| Quote: | I took advice from an independent optician and he suggested Hoya 1.6 Eyas.
He said (if I understand correctly) that although the Eyas lens geometry
did not specifically deal with barrel distortion he thought it would
at least minimize it to the point of being no worse than the old Zeiss
lenses. Does this sound right?
|
Nope.
| Quote: | I also understand the Hoya 1.6 Eyas has a good ABBE value so it will
minimize the off-axis chromatic aberration (even if this is not a big
issue for me).
Any advice will be received gratefully. My priority is the performance
of the lens, coming well above aesthetics.
|
Your optician might have some success in minimizing the awareness of this
distortion (barrel) with your existing glasses by adjusting the panto (vertical
tilt), the dihedral angle/facial wrap (horizontal tilt), and by reducing the
vertex distance (moving the lens closer to the eyes).
Hope this helps,
Robert Martellaro
~~~~~~~~~~~~~~~~~~
Optician/Owner
Roberts Optical
~~~~~~~~~~~~~~~~~~
"If a million people believe a foolish thing, it is still a foolish thing."
- Anatole France |
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John Phillips
medicine forum beginner
Joined: 08 Jul 2006
Posts: 4
|
| Posted: Mon Jul 10, 2006 8:56 pm Post subject:
Re: Selecting lenses
|
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|
On 2006-07-10, Robert Martellaro <robopt@nospam.com> wrote:
| Quote: | On 08 Jul 2006 18:05:34 GMT, John Phillips <news0309@DontUseThis.mainly.me.uk
wrote:
SPH CYL AXIS PRISM BASE VIA
R -2.25 -0.50 52.5 - - 6/6
L -2.00 - - 6/6
I have worn Zeiss CR-39 lenses (no other details, I'm afraid) to a
very slightly different former prescripton for many years with complete
comfort.
A new optician (I moved) tested me and ordered me some 1.6 index lenses
from Shamir for some new rimless frames (Lindberg Spirit) and I have
been getting used to them for three weeks.
The new prescription (above) is fine on-axis.
I can tolerate the much increased off-axis chromatic distortion.
However the off-axis barrel distortion is too much. I no longer feel
nausea, but after three weeks I still feel far too uncomfortable in
confined spaces such as the aisles at the supermarket. I suspect it
will not get much better with more time.
Blur, color, or both?
|
No colour problems now unless I deliberately look, when it is quite
visible. However, I seem to have got used to it.
In static situations I can focus now on objects in my peripheral vision
(it was a problem initially but I seem to have adapted). Nevertheless
in confined static situations (e.g. an elevator/lift) the horizontal
displacement at the top & bottom of vertical lines is an extimated 5%
of the vertical distance, which makes me feel uncomfortable.
And as I walk down a supermarket aisle looking ahead I see both
peripheral blur and the horizontal displacement at the top/bottom of
vertical structures. That combination feels very uncomfortable still
after three weeks.
| Quote: | Chroma should be imperceptible at this power.
|
My prescription seems rather mild in the grand scheme of things so the
aberrations seem rather surprising to me. They seemed also to be rather
unusual to the independent optician I consulted. He told me he was
wearing -11 Hoya 1.6 Eyas lenses and these were no problem at all to him.
That's why he suggested those lenses.
| Quote: | There may be
other problems that need correcting e.g. waves, warpage, incorrect lens
positioning.
|
OK. Thanks for that. I don't specifically understand the terms waves and
warpage in this context but it's something I will pursue with my optician.
| Quote: | Is there some specific lens product I can ask for which will minimize
the barrel distortion in a 1.6 index lens?
Nope. Moving the lenses closer to the eyes will help. Contact lenses would help
the most.
I know some barrel distortion off-axis is normal but does it always get
so much worse with 1.6 index lens material?
It's not the lens material, it's the lens positioning.
|
OK That's something I will pursue.
| Quote: | I took advice from an independent optician and he suggested Hoya 1.6 Eyas.
He said (if I understand correctly) that although the Eyas lens geometry
did not specifically deal with barrel distortion he thought it would
at least minimize it to the point of being no worse than the old Zeiss
lenses. Does this sound right?
Nope.
I also understand the Hoya 1.6 Eyas has a good ABBE value so it will
minimize the off-axis chromatic aberration (even if this is not a big
issue for me).
Any advice will be received gratefully. My priority is the performance
of the lens, coming well above aesthetics.
Your optician might have some success in minimizing the awareness of this
distortion (barrel) with your existing glasses by adjusting the panto (vertical
tilt), the dihedral angle/facial wrap (horizontal tilt), and by reducing the
vertex distance (moving the lens closer to the eyes).
Hope this helps,
|
Many thanks to you and to all others who have offered suggestions and
points to examine. I will pursue these with my optician.
--
John Phillips |
|
| Back to top |
|
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Mark A
medicine forum Guru Wannabe
Joined: 30 Apr 2005
Posts: 226
|
| Posted: Mon Jul 10, 2006 11:51 pm Post subject:
Re: Selecting lenses
|
|
|
"John Phillips" <news0309@DontUseThis.mainly.me.uk> wrote in message
news:slrneb5fo1.c91.news0309@linux.mainly.me.uk...
| Quote: |
No colour problems now unless I deliberately look, when it is quite
visible. However, I seem to have got used to it.
In static situations I can focus now on objects in my peripheral vision
(it was a problem initially but I seem to have adapted). Nevertheless
in confined static situations (e.g. an elevator/lift) the horizontal
displacement at the top & bottom of vertical lines is an extimated 5%
of the vertical distance, which makes me feel uncomfortable.
And as I walk down a supermarket aisle looking ahead I see both
peripheral blur and the horizontal displacement at the top/bottom of
vertical structures. That combination feels very uncomfortable still
after three weeks.
|
Find out if you got polycarb. If so, take them back and get one of the other
lenses recommended in this thread. I promise that you will see the
difference. |
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