Which eyepiece diopter?

S

squirrel$$$bandit

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So, with my glasses on, I can't see the full field of view in my R3M's viewfinder. I assume I need an eyepiece diopter. But which one? I asked Stephen Gandy and he said "consult your eye doctor."

I'm nearsighted. By a large amount. My glasses are thin but have a very strong prescription. Is this relevant? I thought the diopter just allowed you to see more of the field of view from slightly farther away from the eyepiece?
 
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afaik, -3 ... +3 are readily available (full steps).
your optician will be able to fit a tailor made bigger value correction class: in that case, get a 0 dpt eyepiece.
i found a cheap nikon (FM/FE/F2) style 0 dpt eyepiece on a photo flea market.
 
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I guess I've been misunderstanding the purpose of these--so they are in order that you can take pics WITHOUT your glasses? That's not a possibility for me; my vision is too poor. And I dislike contacts.

I suppose there's no other solution though? Needless to say, this isn't the only camera I have this problem with, but the enormous 1:1 VF makes the problem more pronounced. I do know I don't have the problem with some cameras, though, like my Canon DSLR, where I can see the whole frame.

Part of my confusion comes from changing the built-in diopter settings on my Contax G1...it seems to make the image grow or shrink, not just change how clear it is. Are there +/- eyepiece magnifiers?
 
What is your eyesight prescription? The off-the-shelf diopters correct for spherical. They are for when you want to use the camera without glasses. If you have a strong cylindrical correction, a standard screw-in diopter will be not very good, but maybe better than nothing.

The diopters do make a small difference to viewfinder magnification, but that is not their purpose. There are screw-in magnifiers, but if you need correction that would be the first priority imo.
 
Yes, they are for using the camera without glasses. I have astigmatism, I believe nothing can be done about making a diopter for me. Not to mention, I'd hate it. I can't see a THING without my glasses. I'd have to doff them to take the photo, then put them back on again immediately. PITA.

I'm a strong correction anyway. -6.25 od +2.75 cyl 4 axis and -6.50 os +3.25 4 axis. Whoo-buddy. Blind as a bat.
 
It sounds like what you want is a de-magnifier. There are plenty of magnifying diopters that you can get (usually used with long lenses), but I've never heard of screw-in diopters that reduce the viewfinder's magnification. Perhaps a better solution would be to trade in the R3A for a camera with lower magnification, such as an R2A or an R4A?
 
One problem with making an eyesight correction diopter for someone with lots of astigmatism (i.e. having a large cylindrical component in their spectacle prescription) is that when the camera is turned 90 degrees to take a portrait, the correction is turned to the most destructive angle and is much worse than no cylindrical correction. The obvious solution is a square format camera so that there is no need or no point in turning 90 degrees. The Mamiya 6 would be good.

The other problem is actually getting someone to make it. Off the shelf prescription lenses can be acquired thru optometrists, but cutting them to fit a round or rectangular frame for a camera is not easy (I'm told).
 
john_s said:
One problem with making an eyesight correction diopter for someone with lots of astigmatism (i.e. having a large cylindrical component in their spectacle prescription) is that when the camera is turned 90 degrees to take a portrait, the correction is turned to the most destructive angle and is much worse than no cylindrical correction. The obvious solution is a square format camera so that there is no need or no point in turning 90 degrees. The Mamiya 6 would be good.

The other problem is actually getting someone to make it. Off the shelf prescription lenses can be acquired thru optometrists, but cutting them to fit a round or rectangular frame for a camera is not easy (I'm told).
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That makes sense. Thanks for the info.

With respect, if you aren't as blind as I am, you have no idea what it is like to take off your glasses and then function. Let's put it this way - if I set my glasses down and someone moved them - say three feet away - I'd be unable to locate them again except by luck.

So the chances that I am going to take my glasses off to use a camera are nil. I won't do it. The moment my camera would come down from my eye, I'd be helpless until I put my glasses back on. PITA at best, recipe for disaster at worst. Nope, not happening.
 
Andrew Sowerby said:
Perhaps a better solution would be to trade in the R3A for a camera with lower magnification, such as an R2A or an R4A?
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*sigh* I've considered this several times over the past few days. But I REALLY LIKE the camera. There is definitely a part of me that wishes I'd gone for the R4A instead of the R3M, but...
 
I'd consider...

I'd consider...

finding a camera that is glasses friendly. Going to a decreased magnification won't help focusing with fast long lenses and with close subjects.

I agree with the above that for nearsightedness greater than -2 or -3, you don't want to be using the camera in place of your glasses, especially with astigmatism.

You can however, possibly reduce your nearsightedness with eye exercises and the use of positive (relative) magnification lenses - see your eye doctor and check out myopia.org and books like the secret of perfect vision and sites like powervisionsystem.org - there is science and proven studies behind these techniques, and now also products (expensive) that I myself am leery of, though I would not be surprised if they become refined and begin selling for less in the future:

http://item.rakuten.co.jp/bicymt/c09_eyepower_01/

http://gizmodo.com/gadgets/snake-oi...ure-or-one+way-ticket-to-blindness-327974.php


mabelsound said:
*sigh* I've considered this several times over the past few days. But I REALLY LIKE the camera. There is definitely a part of me that wishes I'd gone for the R4A instead of the R3M, but...
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I wrote to Stephen proposing I return the R3M and get an R2M or R2A. But he said the camera must be absolutely scratch-free to returned, and I found a little one on the bottom plate. I set it down on some gravel yesterday while tying my shoe.

Anyway, it's not a big deal. If he won't take the camera back, like I said, I'll just deal with it. Stuff does not have to be perfect at all times, and I otherwise have no complaints with this awesome camera.

I think I'll get some contacts though, so I can wear them on big photo days. I don't like them, but it seems the lesser of two evils.
 
By the way, this is what I want, except to fit the Bessa. If I buy any old diopter lens, would my optometrist be able to replace the glass with a lens that would DEMAGNIFY to like .7 or something, so I can see the whole FOV with glasses on?
 
ampguy said:
You can however, possibly reduce your nearsightedness with eye exercises and the use of positive (relative) magnification lenses - see your eye doctor and check out myopia.org and books like the secret of perfect vision and sites like powervisionsystem.org - there is science and proven studies behind these techniques, and now also products (expensive) that I myself am leery of, though I would not be surprised if they become refined and begin selling for less in the future:
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That stuff was around when I was a kid. It was a scam then, it's a scam now.

This doesn't bother me much - nobody is going to die from this. But it's cut from the same cloth as the guys who started approaching my dad when he got throat cancer. I don't know how they find out, but he apparently wasn't the only one, they used to talk about it in the waiting room where he got his radiation treatments. These scam artists latch onto people's hopes and feed on their fear and take their money. I'd love to catch one someday.
 
whoa

whoa

I'm just stating my experiences. No need for you to believe them or attribute them to unrelated illnesses. Nobody that I know is making money from my opinions on myopia.

bmattock said:
That stuff was around when I was a kid. It was a scam then, it's a scam now.

This doesn't bother me much - nobody is going to die from this. But it's cut from the same cloth as the guys who started approaching my dad when he got throat cancer. I don't know how they find out, but he apparently wasn't the only one, they used to talk about it in the waiting room where he got his radiation treatments. These scam artists latch onto people's hopes and feed on their fear and take their money. I'd love to catch one someday.
Click to expand...
 
ampguy said:
I'm just stating my experiences. No need for you to believe them or attribute them to unrelated illnesses. Nobody that I know is making money from my opinions on myopia.
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This is a rather low-risk form of it, but snake oil is snake oil, so the comparison is valid.

http://www.allaboutvision.com/buysmart/see_clearly.htm

Sorry, nothing against you. I calls 'em like I sees 'em - and I sees 'em with my glasses on.
 
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