A reader writes:
I'm getting older, which is better than the only alternative, but reading small print started to get difficult, so I bought reading glasses on eBay for $3 delivered and... problem solved!
Except now I think I may be slowly blinding myself by using $3 glasses. Especially after what you said the other day about eye damage often not being noticeable until it's really bad.
Are cheap reading glasses dangerous?
Andre
You're not blinding yourself. Cheap reading glasses are a perfectly acceptable treatment for hyperopia (longsightedness).
You won't be able to focus far away while wearing even weak reading glasses (for the same reason that adding filter-thread magnifiers or extension tubes to camera lenses prevents infinity focus), but the only danger this poses is if you decide to go driving with the reading glasses still on.
It's actually pretty much impossible to damage your eyes by wearing the wrong glasses, although you certainly can give yourself a headache. There are all sorts of folk legends about how you can damage your eyesight by sitting to close to the TV or cure your myopia by doing eye exercises or massaging your eyeballs, possibly with some gadget or other, but it's all claptrap.
(It'd be nice if you could focus close and then far away and then close and then far away at some sort of eye gym and thereby cure the optical shortcomings of your particular set of eyeballs, but there's no good evidence to suggest that this is possible. Fortunately, spectacles and contact lenses are now very mature technology, and the various forms of refractive surgery are getting better and better.)
In the olden days, mail-order spectacles were exceedingly likely to be a scam, on account of how the notion of an eyeglass prescription didn't yet exist, so it was impossible for even an honest mail-order glasses dealer to actually know what glasses you needed. This didn't, of course, stop mail-order outfits from making the usual pre-consumer-protection outrageous claims about their wonderful products, and separating countless suckers from their money.
A significant portion of the mail-order hucksters' business, though, was simple mild-magnification reading glasses optically much the same as the ones you bought on eBay, As long as the people who bought those glasses really were longsighted, many of them were probably perfectly happy with their purchase (although it's likely that they were still paying more than they needed to).
Should your need to see stuff close up move beyond "reading books" and into "working with small objects, and wanting to look as much as possible like a mad scientist while I do it", allow me to recommend the Donegan Optical Optivisor. The Optivisor works very well (it's comfortable, you can easily flip it up when you don't need it, and interchangeable lenses are available for different magnifications), it looks pretty hilarious, and it isn't very expensive.
1 February 2012 at 10:56 am
Heh. My dad had a pair of the Donegans he used at work (camera repair). I swear they're older than me.
1 February 2012 at 6:13 pm
Heh heh, eyes are funny things. I've been wearing glasses since childhood - however, not a standard set, but a significantly mismatched one: one of the lenses is around -4.5 dioptres.
Interestingly enough, while I can't see anything clearly with that eye more than a foot away without the glasses, it also got me my very own special "superpower" - (drum-roll and all that) MICRO-VISION! As in, I can look at stuff from really, really, really close up and still see it clearly - like reading values printed on 0603 SMD resistors without problems - and these buggers are about 1.5x0.8mm big. I have to say this comes in rather handy when one has an interest in the oh-so-fashionable Magic Smoke Taming branch of Mad Science also known as "electronics".
Now I do understand this sort of thing is not an automatic bonus that comes with needing glasses, I just wanted to note that - even though I generally dislike that kind of philosophy - sometimes there can be a "silver lining" even to poor eyesight... :)
2 February 2012 at 4:19 am
My eyes are around -8 and -6.5 dioptres. Until this post, I never thought it was unusual to be able to read the writing on surface mount devices.
Anyone with normal eyes want to chime in?
--Me
4 February 2012 at 2:42 am
I have one relatively normal eye (-0.25 or so) and one around -2. I can confirm that it's pretty hard to read the text on 0603 SMD's with the good eye without using a magnifier.
2 February 2012 at 6:16 am
I also have micro-vision with my glasses off. I love to be able to do close work without artificial magnification. But I can't focus on anything beyond a foot from my face.
6 February 2012 at 1:44 pm
I believe the original writer Andre is "suffering" from a condition called presbyopia. It is a condition noticed in most 45+ year olds, which causes symptoms very similar to hyperopia. Basically, people need reading glasses from 45-50 onwards, or a slight change to their normal glasses if they already wear glasses.
(disclaimer - written by Australian optometrist)
29 February 2012 at 3:48 pm
I have terrible vision, but the micro-vision effect is so strong for me that I can read the microprinting on banknotes, never mind the fiddling little text on electronics components. This was an especially handy thing when I worked in an electronics shop; not only could I easily look at very small things, I could also easily check that I was not given counterfeit money!
1 September 2012 at 9:46 pm
I recently found this at a market stall offering all kinds of tools. It was next to the loupes and magnifying glasses, so it was pretty clear what it was supposed to do.
https://twitter.com/PPvG/status/240558282538876930/photo/1
Turns out it's way too strong for what I normally want to use a little magnification for, like SMD work, (my Donegan's are in the mail); its focal plane is at 10cm (4"), but for the occasional fiddly microscopical stuff involved in repairing cameras it comes in quite handy. Especially since you can easily switch between normal vision and magnification by shutting one or the other eye.
And it gives one that nice evil mad scientist appearance.