Monocle Power vs Diopter

[Mike G]

This is for Rob or anyone else who wants to take a crack at it.

Background: Thanks to the toric lenses that replaced my cataract ridden OEM lenses, I have very good distance vision uncorrected. But I still need 1.5 diopter cheaters for close up. On and off I see monocles recommended for close fishing tasks. They are smaller and easier to transport than readers.

Problem: But monocles are rated in power rather than diopter. So how do I convert 1.5 diopter to power, Rob?

Besides: Monocles look cool.



Zehr sexy!

[Terry Dodge]

That's what I need. Where do I get one?

[Rob G]

It seems quite expensive to me but here you go, a +1.50 monocle

 

http://www.eyeglasses.com/glasses/chakra-eyewear-monocle.html

 

I can make one for you in the lab in about 5 minutes if you don't require a frame but we don't get a whole lot of requests for monocles. Unfortunately with the use of a monocle, one loses depth perception and often some resolution since only one eye will be focused at near vs. with your cheaters which allow both eyes to see up close simultaneously. That may or may not hinder you when you go to tie on that size 20 midge.

 

Oh, and magnification and dioptric power, though somewhat related are actually two different creatures. Hope this helps

[Terry Dodge]

I can make one for you in the lab in about 5 minutes if you don't require a frame but we don't get a whole lot of requests for monocles. Unfortunately with the use of a monocle, one loses depth perception and often some resolution since only one eye will be focused at near vs. with your cheaters which allow both eyes to see up close simultaneously.

 

What lab are you working in?

[Rob G]

Terry,

we have an optical lab on site here at our office. In other words, we grind, surface and edge our glasses right here and only have to send out to outside labs for specialty items or processes. Cutting a round +1.50 lens takes only 2 minutes, but unfortunately I don't have a monocle frame in which to insert the lens or I would make some up and bring them this weekend for you guys to try. Truthfully I would stay with the cheaters or get the magnifiers that attach to the bill of one's cap which is what I often use since they're so easy to flip down when needed and flip out of the way when not. The golden rule is: always try to use the least amount of magnification possible in order to achieve your desired task at hand.

[Mike G]

Rob,

 

Thanks for your suggestions. After I had my eyes reworked. I had to revise my fishing eyewear. I was delighted to find that there were good polarizing bifocal sunglasses at reasonable prices. But I hit a wall when it came to finding yellow, polarizing sunglasses with the bifocal inserts. I got a pair of plain yellow polaroids for low light fishing. But that means I need something for close work. I thought the monocle would solve my close vision problem. But I was surprised at the cost compared to readers.

 

Now those clip to cap magnifiers seem like the real solution for low light. The price is reasonable. I just have to figure out the best magnification level. There is see a formula: Magnification = Diopter/4 + 1. Right now I am thinking magnification around 2 might do it.

[Scott Ferguson]

I use clip on, flip up reading glasses that attach to my sunglasses. They aren't real easy to find but you can get them online or sometimes at stores that sell knitting and sewing items. I find bifocals distracting. When you aren't using the clip ons, they flip up out of your vision.

 

 

[Rob G]

There is see a formula: Magnification = Diopter/4 + 1. Right now I am thinking magnification around 2 might do it.

 

Mike,

it's not quite that simple. You probably realize that magnification is distance dependent. If you put the item to be viewed directly next to the lens with your eye on the other side, the only magnification you will achieve, which is minimal, will be due to the thickness of the lens itself and not the dioptric power of the lens. As you move the item further away from the posterior surface of the lens, the greater the magnification. I hated to state the old Diopter/4 = magnification because it doesn't give you the whole story.

 

Also, as to standard bifocal polarized lenses, these are the available colors below that we have easy access to. Unfortunately, a yellow hazemaster is tougher to come by although you can probably find some that are molded, but not optically ground, plano sunglasses (No Rx in the top with a flat top segmented bifocal) Unfortunately, you'll definitely lose some level of polazation with those.

 

http://www.youngeroptics.com/nupolar_colors.aspx

 

I do have friends that swear by the copper color when on the water but I'm not sure I see it?

[Kev-mo]

 

http://www.youngeroptics.com/nupolar_colors.aspx

 

I do have friends that swear by the copper color when on the water but I'm not sure I see it?

 

I don't know about copper on the water but my brother had a pair of Oakleys years ago that were copper colored/tinted and these seemed to be the best tint for the sun when it is low on the horizon and blinding you while driving. Any thoughts on that?

 

 

Also quick question regarding; "The golden rule is: always try to use the least amount of magnification possible in order to achieve your desired task at hand. " Is this because the eye(s) get lazy if you don't make them work?

[Rob G]

Kevin,

yea, to some degree the eyes might become "lazy" and yes we want the accommodative system to continue to work as we age but more so, psychologically people often find they tend to rely on them more (which will happen anyway as we age). Also the stronger the lens system or higher magnification, the greater the chance that we introduce greater aberrations into the optics and as the dioptric power increases ---> the focal length and depth of focus decreases and we as humans do far more things at arm's length than we do 12" in front of our face.

 

Mike,

in accordance with your formula and your desired magnification of 2x, you would need a +4 diopter lens but on the other hand you stated that readers of +1.50 are adequate. Now you see why it's problematic.

[Mike G]

Rob,

 

I find it interesting that I hardly find magnifiers below 2x when I shop around. On the other hand sites that sell equivalent readers in 4.0 D warm you that that high a power cannot be sold legally in some states. Shopping my favorite tackle online site, Amazon, I found these for a little over $10. They might do the trick when I use the yellow polaroids that do not have reading inserts.

 

[Rob G]

Mike,

they should work like a charm as this is similar to what I use, I think mine are 1.5 or 1.75X. I agree with everything on the video except for one little tidbit. At the end he states they can be used for reading and fly tying which is true as long as it is short term use of not more than a few minutes. But if you intend to sit down and read a novel, using strong magnifiers like this will cause many individuals to develop eye strain, headaches or eye fatigue because they are not designed for their individual eyes. To mass produce these, you have to make a few assumptions, such as

1. both eyes are of exactly the same Rx, (which is rarely the case)

2. the individual has the same exact distance between his pupils as to where the optical centers of the magnifiers will line up (again, you might be lucky or close to that distance but if not, then the magnifiers create undesirable prism

3. must assume the person has no astigmatism which these do not correct for.

 

Again, for short term use, they're great but don't plan on spending long hours at the fly tying bench using these,

[Mike G]

Thanks Rob.

 

That is a good warning for the general reader. I would not be using these for long periods anyway just on the water for occasional tying of knots. For reading and tying I would use reading glasses or bifocals anyway.