I've had a pair of Zeiss glasses I've been using, and my prescription needs redoing. I need some more optics help from someone:
I hear that there are "computer glasses" that work out to 6-9 feet. Then you use another pair of glasses for driving. Zeiss calls their version "Gradual RD", but I don't know if it's glass or plastic. Any light someone can shed on any of this?
Another quandry is just what magnification is best to use when looking through viewfinder. Does the close-up, reading part get used most effective, midrange, or far distance correction? Seems to me that if I got a pair of progressives that went from 1 foot out to only about 6-7 feet, that THAT would be just fine for the viewfinder...I wouldn't be using the distance glasses IOW? I think that the camera redirects anyone's vision out to a few feet, that is both viewfinder info and the frame viewed are sharp at an imaginary point a few feet in front. If that's so then midrange vision correction in glasses helps for viewfinder...or is this erronious?
Or would the little diopter wheel (on Canon 20D) just take care of whether one used mid-ranged or far distance glasses?
Another issue is viewfinder squash. I use my left, not my right eye, as it just sees better- or is a habit. It refocuses much quicker than right eye. So my right lens is often banging into the camera body and the left is at a slight angle to the plane of viewfinder. And my nose fogs up the display. Would a "memory-metal" type frame, that has lot's of bend in the bridge and temples work here? I could just get in a little closer and the glasses could spring back afterward (!).
Optically clueless,
Jim Hayes [img]/ubbthreads/images/graemlins/smile.gif[/img]
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The best advice would probably be to take your camera along when you have your eye exam and explain the range of vision you need. Remember you need to be able to see the LCD and the subject as well as through the viewfinder, which is a tall order for single vision glasses, depending on how strong your prescription is. The problem with varifocals, which is what I think you may be refering to, is that you might find it difficult to see through the viewfinder.
My latest thought on the matter, after some research is two pairs.
One pair would be the Zeiss "Gradual RD" or similar....."computer glasses". graduated from reading distance to about 6-9 feet. These I use indoors, or at the computer, or examining prints, etc. Unfortunately these are only made in CR-39 AFAIK, so no glass. But a Zeiss USA tech told me she imagined that plastic "RD's" would be better than glass progressives. Certainly would want anti-scratch coating, but not sure about anti-glare (?). Does anyone have experience with this flavor of eyewear-computer glasses?
Second pair would be bifocal with a split line moved a little downward on the lens, and made of glass. So the top would be distance, bottom for reading. This pair is then used for driving, walking around outdoors in open spaces, and with cameras- the upper distance part for viewfinder, lower for reading display, dials, etc. If I see something about 7 feet away I want to shoot, I guess it will be a tiny bit blurry, until I look at it thru viewfinder.
Any comments on the above or any other methods that have worked for you as your eyes get older?
I'm 59 and have the standard presbyopia problem, and I wear Silouette lighweight progressives with scratch-resistant and photosensitive coatings when I shoot with my 1DMkII (and the 1vHS before it). My glasses are set up for 14-18" reading at the bottom, a mid-range slice (don't know the intended distance), and long-distance viewing at the top. My distance prescription is pretty mild, as I'm about 20/40 with no assistance in the longer range. I wear the progressives because I just found it to be a pain to be taking reading glasses off and on all the time. Also, when I drive with no glasses, the scene outside the car is fine, but I can't read the dashboard.
Once I got used to the progressives in general, which takes a few weeks, I have had absolutley no problem seeing through the viewfinder with the longer range prescription and switching to the reading range for the information at the bottom of the display with no conscious thought at all. In fact, until you asked this question, I hadn't even thought about it. Without the glasses, I can't see diddely when it comes to the numbers at the bottom. Most of the time, I wear these glasses for everything I do. Once in a while I get tired of glasses in general, since I never wore than at all until I was well into my 40s and find them to be a pain, and just take them off and drive without the stinking dashboard input for a while.
I'll be 55 in July. I've been wearing eye glasses since third grade and currently with out them on, my eyes focus at about 8". Current eye glasses are Zeiss progressive with anti glare and scratch resistant coatings. Current Rx is -5.75 W/astigmatisim correction and reading Rx of +1.5. Frames are Safilo metal with the elasta hinge. I have a couple of them same frame with a lower Rx for reading at +1.25. I too have a stronger left eye vs the right eye. I'm due to get an exam soon and going to insist on a better correction of the right eye. Reason, I have to do some work for some people with a Fuji S2 ( lousy view fineder ), I've owned the Canon D30, D60, 1D, and now use the 1DMk2 camera bodies. I found that the view finders in the 1.5 and 1.6 factor cameras are a pain to see through with eye glasses and near impossible to manual focus, they even were not designed to be used as manual focused, this comment is from some of the folks at Canon USA. The cameras in the 1D series are designed to be manual focused though. That combined with the larger, brighter and more contrasty view finder make it way easier to use the camera especially with eye glasses.
I've looked at using soft contact lenses again, due to the use of AF, with the combination of reading glasses for computer work and reading. The problem with soft lenes in the past on manual focus is the way the lens distorts as you look through the viewfinder causing you to loose accuity needed to confirm focus. What I'm findind about the progressive glasses after using them for 6 years is that they have a very small sweet spot for infinity focus, this is the point you use when viewing through the viewfinder. Then when you go to use the computer, I find I have to raise my chin and nose to view the monitor properly, this causes neck and back strain ( did I mention that after carring 30 lb camera bags for years on one's left shoulder is bad for the back and will take it's toll? )
So at this point, I realize that my course of action is to go with a new Rx keep the old frames which are non flex type, get a good Rx for the right eye, and use that eye for viewing the viewfinder. Get a second Rx for working at the computer, these glasses will have a Rx for about 24" to 36", and as such will allow me to sit naturally when working on the computer. I tend to hold on to several pair of frames that are identical if at all possible. The reason is spare parts, the ability to have a weaker Rx available which tends to forstall the need to migrate to a stronger Rx.
Other options as I see it are the contact lenses in conjunction with reading glasses, workable due to the excellent AF of the cameras now days. With old hard lenses I was able to achive 20/10 vision, but with soft contacts it is around 20/20 to 20/40 depending on how my facial muscles distort the soft lense when looking into the viewfinder.
I wondered about LASIC surgery, but as I understand it....I only will be given two eyes this time around and I do not warm to something that if it goes wrong can pretty final. Also the surgery is normally on average able to get one to 20/40, and with people who are misson crital with accuity issues ( photographers ) it is some times not recommended.
The Ziess progressives are good lenses. Mine are plastic, and I think they all are, but could be wrong. I'd get lenes that are progressive, anti glare, anti scratch, and shatter resistent. I wish that the sweet spot in the lense were a bit bigger for infinity focus though... I'd advise staying away from glass of any kind do to the risk of breakage as well as it's weight.
Yoga exercises for the eye are also very good to practice in that they work the muscles that we use to work the eye. As we age the eye & muscles used stiffen up a bit and these exercises help counter that.
Of course all of the obove is only in my humble opinion, gathered from wearing the blasted things for about the last 45 years, and your milage may vary.
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Yoga exercises for the eye are also very good to practice in that they work the muscles that we use to work the eye. As we age the eye & muscles used stiffen up a bit and these exercises help counter that.
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Where can one find out more about these exercises?
Some great information there from Steve. Bob, I have the plastic lenses, in my case they are made by Nikon, and prefer them to glass. The anti scratch coating in particular is worth having, my lenses remain as good as new despite constant jamming against the eyepiece. Like you, I use my left eye, although it's my weakest, funny how you're either left or right eyed.
I'd be very wary of laser surgery. Recent reports here in the UK place the failure rate as high as one in ten and with age related long-sightedness it would probably only be a short term solution.
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