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Improve your bino with new eyeglass frames (1 Viewer)

A2GG

Beth
United States
Recently I switched eyeglass frames (new prescription) from plastic to thin titanium frames. The new frames are more expensive, but they're supposed to be indestructible. They don't bend out of shape. They're made of titanium and surgical steel.

I wore the new glasses with my 7x42 Ultravid today and with the Swaro CL 8x30 (old version) last weekend. I expected there to be a difference with the CL. Ease of view and eye placement is noticeably better. I didn't expect any real change with the 7x42, but there is improvement. Ease of view is even better surprisingly. also, my new prescription is only a minor change, but the view through the Uvid+ today seemed slightly more transparent. Really enjoying my binos with this new eyeglass frame. They're putting the new lenses in my old pair and my old sunglasses frames. I'll be using the new frames mostly for bird watching with the bins.

Just wanted to share my thoughts and experiences with the thinner frames.

Here's the one I got:

https://ovvooptics.com/shop/optical/surgical-steel-titanium/style-3665/
 
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I also have the thin titanium frames and it does make a difference. I also have glass lenses and that also makes the view more transparent than my other glasses.
 
Timely post for me also.
I’m in Arizona right now on a birding trip, but when I get back I’m looking at getting Flexon frames with high index Zeiss glass lenses in a smaller eye size to fit closer in to my eyes. $800 glasses but they promise good performance. Plastic, even polycarbonate, is a step down to glass IMO.
 
GG,

Metal or rimless frame designs often have nose pads which can be altered to adjust the eye to lens distance (vertex). Obviously facial features are a factor too. My optician tells me about 12mm would be typical for his customers but had recorded low as 6mm and as high as 22mm. With an average lens thickness of 4mm, and a perhaps a 2.5mm recessed eyepiece lens on a binocular it means those average customer would need about 18.5mm ER. With nose pad adjustment and thinner high index lenses that could be readily reduced by 5 or even 6mm. Personally, a 10mm vertex and 1.6 index lens works well with almost all birding binoculars I've tried.

Just a cautionary note. For those needing 4d or more correction, the prescription will need to be altered according to the vertex distance, and tilt, if you use progressive focus lenses.

Kevin,

I discussed glass and plastic lenses with my optician, and his view was the main criteria was firstly shatter versus scratch resistance and secondly weight. I recall my early polycarbonate lenses scratched very easily, but it hasn't been an issue at all with my recent coated prescriptions. Plastic is much lighter and can match or exceed glass for optical properties, but the top specified designs can be more expensive. I chose Zeiss plastic. Your priorities may be different.

David
 
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Timely post for me also.
Plastic, even polycarbonate, is a step down to glass IMO.

I don't wear prescription glasses, but this is my experience with nicer several brands of sunglasses also. I have Costa del Mar (5 pairs), Maui Jim (1 pair) and Ray Ban ( 1 pair) and ALL are nicer than any plastic lenses I tried (within the same brands plus Oakleys, for which I wore exclusively in the 90s and early 2000s) IN SPITE of all the marketing (nice way of saying "lying" :-O ) the industry puts out hyping the easier and cheaper to make (and higher profit margin???) plastics/poly-carbonates.
 
GG,

Metal or rimless frame designs often have nose pads which can be altered to adjust the eye to lens distance (vertex). Obviously facial features are a factor too. My optician tells me about 12mm would be typical for his customers but had recorded low as 6mm and as high as 22mm. With an average lens thickness of 4mm, and a perhaps a 2.5mm recessed eyepiece lens on a binocular it means those average customer would need about 18.5mm ER. With nose pad adjustment and thinner high index lenses that could be readily reduced by 5 or even 6mm. Personally, a 10mm vertex and 1.6 index lens works well with almost all birding binoculars I've tried.

Just a cautionary note. For those needing 4d or more correction, the prescription will need to be altered according to the vertex distance, and tilt, if you use progressive focus lenses.

Kevin,

I discussed glass and plastic lenses with my optician, and his view was the main criteria was firstly shatter versus scratch resistance and secondly weight. I recall my early polycarbonate lenses scratched very easily, but it hasn't been an issue at all with my recent coated prescriptions. Plastic is much lighter and can match or exceed glass for optical properties, but the top specified designs can be more expensive. I chose Zeiss plastic. Your priorities may be different.

David

Good information there David thank you. My biggest issue with plastic is getting scratched. My current glasses are in kind of poor condition from using them with binoculars.
I am in no hurry as I primarily use contacts but I’ll investigate this a little more when I get back.
 
I've only had the polycarbonate lenses and can't comment on glass.
I like the durability and lightness of the poly. I've never had a bad or noticeable
scratch on any glasses I've owned. I'm a bit obsessive about taking good care of them just like my binos.
I'm like this with most things. The poly lenses can exhibit CA but I only noticed this in the beginning and no longer see it.

I don't like the nose pads on my new metal frames. The metal frames are super light and I barely feel them on my face, but I do feel the nose pads. I prefer the plastic frame built in nose "pads". They're more comfortable on the nose and I'll be using the plastic for the work week once they finish fitting the new lenses in them.
They adjusted the nose pads so they are a little more comfy now. Also the arms adjusted so the frame doesn't slip anymore. I used the 8x30 for a short while this morning and happy to say ease of view quite a bit better...no real fuss anymore to speak of.
My prescription is not strong so the lenses aren't thick. With this new frame I think I can use practically any 32mm bin more comfortably now as along as ER is at least around 15mm .
 
As with any other optical glass high index also means high dispersion and, in a single element lens, more CA. High index really only makes sense if one needs to reduce the thickness of high dioptre prescriptions (mainly -ve.) and/or the weight of glass lenses.

Polycarbonate is probably good for chidren's lenses as it's very impact resistant, but on the other hand it's rather soft and has an Abbe no. around 30.

IMO the standard plastic, CR-39, is the ideal material for most applications. It's half the weight of glass, has better UV absorption, high abrasion resistance and optical properties similar to BK7 with an Abbe no. of 59.

John
 
Another thing I like about the poly lenses is their natural protection against UV rays. When I was researching which to get in the beginning years back I decided to go with shatterproof, light weight and natural UV protection of Polycarbonate lenses. I get the anti-glare coating added.
My sunglasses are polarized which is very nice.

I do wonder if regular plastic would be noticeably clearer or not, but I may never know. I think I'll probably stick with the Poly lenses unless something new comes along that would work better for me and is affordable.

Currently, there's Trivex which also is shatterproof, has built-in UV protection and is supposed to be better optically (clearer than the Poly), but it's more expensive.
 
I'm a big fan of glass, and uncoated glass specifically. Doesn't scratch (except in extreme situations) and stays (or is very easy to) clean.

--AP
 
I vaguely remember reading (or my doctor telling me) that, for weak/lower prescriptions, most people won't notice any difference between the different lens types. For higher prescriptions, people may be more likely to see the difference in clarity. I don't know where I got that from, but maybe my doctor told me that when I was trying to decide several years back.
 
Here https://en.wikipedia.org/wiki/Corrective_lens is some comprehensive information with a table of the optical properties of various lens materials. The reflectivity of some of the higher index materials looks rather disturbing, but I suppose modern multicoatings would ameliorate most of this. Also interesting is that the hardness of some coatings approaches that of glass. All in all the disadvantages of high index materials would seem to outweigh their advantages, except of course their profitability ;).

John
 
Good info in that link, John.
I have a strong prescription and plastic is not my first choice.
Maybe I’ll just get O.K. replacement glasses and stick primarily with contacts.
 
The correct prescription, correct placement of the optical center of the lens with respect to each eye and correct fitting definitely help with binocular use, although you can get each of those three right and still see differences created by how far the lens is from your eyes. That’s why I need 16-17mm of real eye relief, which often translates to 20+mm of stated ER.
 
The correct prescription, correct placement of the optical center of the lens with respect to each eye and correct fitting definitely help with binocular use, although you can get each of those three right and still see differences created by how far the lens is from your eyes. That’s why I need 16-17mm of real eye relief, which often translates to 20+mm of stated ER.

Eye Relief is an optical concept and takes no account of how much of it is 'stolen' by they eyecups. Useable Eye Relief might be more useful to us bino users but Eye Relief is defined and agreed internationally and a new concept such as Useable ER would need defining and agreeing and would probably take years to achieve.

Lee
 
That last piece of glass/plastic between you and the image could in many respects be said to be the most important. One has to wonder how many fine binoculars are viewed every day through glasses that are scratched/dirty/dusty...

IMO the standard plastic, CR-39, is the ideal material for most applications. It's half the weight of glass, has better UV absorption, high abrasion resistance and optical properties similar to BK7 with an Abbe no. of 59.

John

Interesting stuff John. Given those properties, and (almost certainly?) greater ease of production than glass, there ought to be applications for its use in quality binoculars eg. in aspherical lenses...?
 
As with any other optical glass high index also means high dispersion and, in a single element lens, more CA. High index really only makes sense if one needs to reduce the thickness of high dioptre prescriptions (mainly -ve.) and/or the weight of glass lenses.

Polycarbonate is probably good for chidren's lenses as it's very impact resistant, but on the other hand it's rather soft and has an Abbe no. around 30.

IMO the standard plastic, CR-39, is the ideal material for most applications. It's half the weight of glass, has better UV absorption, high abrasion resistance and optical properties similar to BK7 with an Abbe no. of 59.

John
All,

I will be looking to update my prescription and glasses latter this year. I expect I will still be a reasonably strong myope (3, 4 or 5D ?) with bits of astigmatism creeping in here and there - no need for bifocals or multifocals etc. I will be looking for light weight, impact resistance (always handy as a just in case), but most important of all 'light "TRANSITION"TM lenses' treatment so that I don't have to have a separate pair of sunnies.

I would like to eliminate CA more than at present, and get some larger frames (probably carbon fibre or titanium, etc) to help matters (my current ones are very trendy Geordi La Forge type slim ! :)

Could anyone update me on the best compromise (highest index + Abbe no.) suitable for such treatment. I pretty much gather that I will be headed down some sort of plastics path, but can anyone give the latest on pro's /con's /costs of the different types of plastics, and glass types .... ? :cat:

Oh, and btw - contacts are NOT an option ! :) Thanx :t:





Chosun :gh:
 
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CJ,

Take a look into Trivex lenses for impact resistance. It should be sharper (higher abbe) and exhibit
less CA than polycarbonate.
It's a little thicker but supposedly even lighter than poly. Probably a little more expensive.
I have poly, but wonder if I should have gotten the Trivex.

Here's a comparison:

https://www.allaboutvision.com/lenses/polycarb.htm
 
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CJ,

Take a look into Trivex lenses for impact resistance. It should be sharper (higher abbe) and exhibit
less CA than polycarbonate.
It's a little thicker but supposedly even lighter than poly. Probably a little more expensive.
I have poly, but wonder if I should have gotten the Trivex.

Here's a comparison:

https://www.allaboutvision.com/lenses/polycarb.htm
Thanks GiGi - I read through that link and the one that John posted earlier. I think I will try and get the best performing glasses possible and hang everything else - cost, looks ! etc ...... :cat:

It will be interesting to see where the photochromic coatings are up to now - apparently some even polarize when darkening which would be handy by the water. Both the Trivex and CR-39 take the "TRANSITION" type coatings. I think a lot will depend on the exact script, but I think I will try and go for the highest Abbe no. possible (to nix the off-axis CA as much as possible), with the most suitable design (which is apparently round lenses with precisely matched spherical curvature for the power - my current ones are just over twice as wide as they are high). Before the current enforced pause to my Bowling career, I noticed that my right eye had just managed to regain a slight dominance again - so hopefully the astigmatism has gone AWOL as well!

I will look like a cross between a Bratz doll with huge eyes, and Steve Jobs indoors, and Morpheous outside! I might also have to get some black leather clip on side covers (for that Lady Gaga steampunk look ! :) . I think a circumference of diamante's (Dolce and Gabbana style) would look really flash - but probably not do much for the stray lighting glare control ! :-O

Hopefully the coatings are much better than the first pair of TRANSITIONS I had - in the end they refused to go fully clear or fully dark, taking on a permanent light brownish yellow Roy Orbison look ! :eek!:

I can also attest to the benefits of impact resistance - my father in his infinite wisdom had a rake leaning against a post tines up ...... which like Wile E. Coyote I promptly stepped on - WHACK ! :eek!: the handle smacked straight into one lens putting a 1cm crack in it and slamming the bridge into my nose for a temporary dent cut.

The lenses now have some sort of weird bifringence pattern through them - though that could also have been when I fell 10ft off a ladder (while putting up bird hollows) and slammed shoulder and head first into the aluminium ladder on the ground. The plastic encased metal frames bent putting a rather cool Z shaped scar right next to my eye (jeez was I lucky !!) :eek!::eek!: The lenses survived ! ....... haha - perhaps I could model for Zeiss now ! :-O




Chosun :gh:
 
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