Prescription for Photographer

Perhaps there is a Photographer Ophthalmologist or Optician that can verify my thought process.

I wear trifocals. Its a pain when using a camera as the lines get in the way. I want to get a pair of photography only bifocals that have a large area to cover the viewfinder and a closeup lens for reading stuff. Am I correct in thinking that I should use the far field correction in the main lens? I would also use these with Binoculars. I need prism correction so going with out glasses isn't really an option.

Thanks in advance.

Not an eye doctor but a long time progressive wearer and yes you are correct. The viewfinder is designed for the image in it to appear at infinity including the information that is displayed around the edge. Most cameras in addition also provide a diopter adjustment so that you can fine tune it to your eye.

I wear trifocals also.
I use the upper/distance lens to look through the viewfinder and either the bifocal or trifocal lens (depending on distance) when looking at the LCD on the camera back when reviewing the image after the shot or setting menus. There is no need for special camera glasses. As E.J. said adjust the diopter setting on the viewfinder to get the sharpest viewfinder image. If you don't know where the diopter adjustment is check your camera manual as the location varies a bit by camera brand but it is usually a small wheel at the lower right hand side of the viewfinder.

The only place where specially designed glasses come in handy is when working on a large computer monitor. In my case I have the upper lens (no distance lens at all) set to a distance that is a bit greater than the regular trifocal distance as I have found I sit a bit further away from the monitor in order to see the entire screen. Be careful to accurately measure the eye to screen distance before going to get your prescription. Trifocal lens prescriptions are normally computed as a percentage of the bifocal prescription which in my case is too close to the monitor when at proper focus distance.

Re: lenses for computer work, there are specially designed lenses for this:

http://www.zeiss.com/vision-care/en_us/ ... enses.html

I know this is not what the OP asked about, but it is something many photographers should be aware of, since we spend a lot of time viewing monitors. Gunnar also makes some especially for gaming. They sure seem to sharpen things up!

Joe

Thanks. Glad to confirm my thought on which lens to use. As for special glasses, the reason I am thinking of getting them is so that I can easily look through the viewfinder without the lens lines being an issue. With today's narrow lenses, I find that I am moving my head too much to ensure I have the top lens only over the viewfinder.

I do adjust the diopter as needed. But that can be a bit of a circular thing....is it the image that is out of focus or is the diopter maladjusted.

mortsgah wrote:Thanks. Glad to confirm my thought on which lens to use. As for special glasses, the reason I am thinking of getting them is so that I can easily look through the viewfinder without the lens lines being an issue. With today's narrow lenses, I find that I am moving my head too much to ensure I have the top lens only over the viewfinder.

I do adjust the diopter as needed. But that can be a bit of a circular thing....is it the image that is out of focus or is the diopter maladjusted.

You are not adjusting the diopter properly if you have that question.   Adjust the diopter using the frame or the AF point array in the viewfinder, not what you are photographing.  It needs to be something that is not dependent on lens focus.  Most camera manuals explain this.

Here is what Nikon manuals say:
Rotate the diopter adjustment control until the AF area brackets are in sharp focus.

For me, I have found the easiest, most efficient way to adjust the diopter is without attaching a lens to the camera body. Just watch the focusing screen while turning the diopter adjustment wheel.

Joe

I agree with Dick,s comments about trifocals. I wear them and love them and use them with my dslrs with no problems. For pc work, I do not use them as I have a special pair of glasses where the top lens is my trifocal prescription (I think) and the bottom window is my bifocal prescription and they have an anti glare coating. My optician said that you can buy reading glasses and use them for pc work. You take your trifocals prescription number and divide it by two. That is the strength of the reading glasses you ought to try out. Then adjust accordingly, if needed. At least that is the way I recall what she told me.

Joe smith

I am a recently retired optometrist (38 years). This is my take. The top of your lenses should be focused for infinity and the camera diopter adjustment set to zero as was stated be several posters above. The choice between trifocals or progressives is a personal one. However, most people will like the gradual change in focal length offered by progressives, if they are fitted well and of good quality. The issue is that many end up not being happy as they get the less expensive brands or go with the standard brand their insurance covers. My suggestion is that there is a difference between brands and models within brands. Kind of like "L" lenses being better than consumer grade. There are several excellent high end brands. The advantage the high end brands have is a wider field of distortion free vision both at distance and near. A lot of progress has been made in the past 5 years designing progressive lenses with wide field of view. so, ask your eye doctor and optician about the best lenses for your needs.

The bottom line is that progressives will give you the most natural vision (but not at all like you were 20 years old again, but you need to choose among the better brands.

I, along with everyone else, really like having a special set of computer glasses for extended work on desk top monitors. Mine have the top of the lens focused for the monitor distance and the bottom for my desk top. They are one of the special "office" progressives. However, many patients were happy with standard progressives set like I mentioned or even wide flat top bifocals to get an even wider field of view.

My suggestion is to ask your eye doctor or optician for their advice. Be sure you have accurate (within 3-5 inches or so) of the distance from your eyes to the monitor as well as your eyes to the desk top when discussing your options.

Sorry for the double post.

The comment above re over the counter reading glasses is correct as long as you do not have significant astigmatism.  If you have more than about 1.00 diopter of astigmatism the OTC readers are not going to give you the best clarity. Of course some are more sensitive to this than others. The math on figuring the power is more complicated than indicated above and depends a lot on your basic prescription.  Ask your eye care professional for advice.

Ed Cordes wrote: Mine have the top of the lens focused for the monitor distance and the bottom for my desk top.  They are one of the special "office" progressives. ..

Interestingly enough, my eye doctor highly recommends something like that. I just ordered a pair like that is for middle-distance and close-distance as per her suggestion. She calls it "computer glasses".

DChan wrote:Interestingly enough, my eye doctor highly recommends something like that. I just ordered a pair like that is for middle-distance and close-distance as per her suggestion. She calls it "computer glasses".

Sounds like you are getting excellent, personalized care. You have a good doc.

I have progressives and have only been wearing glasses a few years and I just can't get used to wearing them in the field. I went to contacts, when I know I am going to be in the field for extended times I use them..

I have the 'computer glasses' too, but don't use them much, still able to work with my monitors without glasses.

However, shooting with trifocals is indeed a problem since the area of 'infinity focusing' is quite small as I use smaller frames.

And if you wear sunglasses (which most of us will be forced to if you are in Africa) the problem is worse.

The best way (for me) that I've figured it is to use the diopter adjustment in camera eyepiece until I can focus with the naked eye correctly. I then lower my eyeglasses just a little bit so I can peer over the rim into the viewfinder when I am shooting. To chimp at the LCD image on the back I simply look through the 'near focus' section of my progressives.

It works perfectly for me. Focusing with my eyes is way easier than moving my head about until the precise part of the progressive lens is lined up against the eyepiece correctly. It is very quick too, almost never feel I am wearing eyeglasses.

Pradeep

Hi Pradeep, Myopia (nearsightedness) has a lot of advantages.  I am the opposite so I am forced to wear correction for anything closer than about 4 feet.  My wife is myopic so she has the benefits that you enjoy.  It does present a  problem when I use her camera and the diopter adjustment is set for her and the viewfinder is blurry.  I either change it or just trust the AF.

Primus wrote:However, shooting with trifocals is indeed a problem since the area of 'infinity focusing' is quite small as I use smaller frames.

I use smaller frames, too, but I don't have that problem with my progressive lenses. I wonder if that has more to do with the making of the glasses rather than it's simply a trifocal or progressive.

DChan wrote:

Primus wrote:However, shooting with trifocals is indeed a problem since the area of 'infinity focusing' is quite small as I use smaller frames.

I use smaller frames, too, but I don't have that problem with my progressive lenses. I wonder if that has more to do with the making of the glasses rather than it's simply a trifocal or progressive.

I does have partly to do with the fabrication - like where the optical centers are.  It also has to do with the basic lens design. The newest and best designs are digitally designed with what they call "Wave Front" and "Free Form" technology.  These lenses have varying power across the lens to compensate for the inherent 2nd order aberrations created by making the blend from distance to near power of the progressive.  Unfortunately, like Nikon and Canon professional camera lenses, this technology does not come cheaply.  I believe, on average, the lenses cost $400 or more per pair.  Like I said - Like professional camera lenses.

Ed I tried progressives a number of years ago, did NOT like them at all.
The problem I had with them was that you needed to keep eye centered left/right on the lens otherwise you lost critical focus. I do a lot of work standing at a table with many items laid out on it. If I moved my eyes left or right with out moving my head I'd lose focus and things would also distort so I had to move my head left and right if I wanted to see everything clearly. This was a real pain. I keep asking if the progressives have widened the the point of critical focus so you don't have to move your head so much and I'm told that yes they've made improvement BUT you still have to move your head left and right in my situation. As a result I use trifocals. I can shift my eyes left and right without a problem and everything is sharp without distortion. I do need a frame that is much higher than what is currently "fashionable" be that is a small price to pay for good vision. The current trend of fashionable eye ware is so narrow vertically I find it hard to understand how they get bifocals in the lens let alone trifocals or progressives.

Yes, Dick, there are people for which progressives just are not right. Don't worry about it. If what you are doing works stay with it. I just wanted to point out that things are better than they used to be. Re frames, I am also one who thinks the current small frame fad is just wrong. I am beginning to see larger frames on the celebs so they must be coming back.

Ed Cordes wrote:. . . .  Re frames, I am also one who thinks the current small frame fad is just wrong.  I am beginning to see larger frames on the celebs so they must be coming back.

The only reason they keep changing frame sizes in the name of fashion is to sell more frames certainly not because they enable you to see better.