Intra-ocular lens implants and colour

[payasam]

Warning: This has nothing to do with rangefinder cameras.

One of my eyes was cut up for cataract in April and the other in May. When I was able to sit at my computer some days after the first surgery, I noticed that the implanted lens gave a bluish image compared with the natural lens still in the other eye. I made two copies of the same TIFF file and adjusted the colour balance of each with one eye until both seemed the same -- when viewed through that eye. Three friends, two of them photographers and one a painter, all said that the image done through the implanted lens was too rich in red. Clearly, I had compensated for a blue which was perceived but not present. I thought it prudent, therefore, to make a half dozen files of different subjects with the eye which did not then have an implanted lens. The idea was to have reference images against which I could compare those on which I worked after the second surgery.

The precaution has proved to be sensible. No one so far has accused me of being a tomato vendor. I also carry a couple of colour prints, of correct colour balance, against which I can compare new ones made for me: it would not be proper to blame others for an apparent defect caused by my own eyes. I am still working on conditioning my head to see everything as a little warmer than it appears to be. That may not be so easy as having a touch-stone.

One would expect implantable lenses to be of neutral colour, but it seems that that is not how they are. Acuvue, a major brand, offers a lens described as "natural". This has a yellowish hue compared with others, which are presumably cold to a lesser or greater degree.

I hope this description of little tricks will help those who are to undergo cataract chopping.

 

[bsdunek]

Interesting! I had lens implants in both eyes a few years ago, and my experience was a little different.
When one was done, it looked more correct to me, while the view through my cataract looked like an old, yellowed photograph. No one has accused me of making things too warm.
Perhaps different brands of implant lenses have a different "color". I actuelly have two different brand lenses, or at least they are from different places. The right one is a Cilco, form Alcon Laboratories in Ft. Worth, Texas. The left one is form Storz Ophtalmics in Clearwater, Florida. I never thought about it, but as I sit here looking at a piece of paper with each eye, the right one may be slightly warmer than the left. The difference is so small that I have a hard time being sure.
I think you have, though, brought up an interesting point; one that should be considered. 😎

 

[pvdhaar]

I have perfect vision, no implants, no contacts no glasses, no nothing. But even I can see a difference with respect to colour between the left and right eye. It has always been like that as long as I can remember. The right eye sees somewhat warmer colours than the left one..

 

[payasam]

Bruce, you treated the implant as correct, while I thought that the lens with which I had lived for so long was correct. The opinions of others told me that I was right. My implants, Tecnis Z9000s, must be more blue than others. They are, incidentally, aspherical, which is said to improve contrast (so long as the ganglions survive, that is) and also to make them work better at different light levels.

Peter, I did not for a moment consider people who are not, er, normal. By coincidence, though, I spoke to an ophthalmologist friend, and one of the things she told me was that differences in the pigmentation of corneas were, er er er, normal.

The more serious question, I think, has to do with the way in which implants are manufactured, the materials that are used, the testing that is done. We cannot assume that all implants are chromatically neutral, as ideally they would be.

 

[bsdunek]

Bruce, you treated the implant as correct, while I thought that the lens with which I had lived for so long was correct. The opinions of others told me that I was right. My implants, Tecnis Z9000s, must be more blue than others. They are, incidentally, aspherical, which is said to improve contrast (so long as the ganglions survive, that is) and also to make them work better at different light levels.

Peter, I did not for a moment consider people who are not, er, normal. By coincidence, though, I spoke to an ophthalmologist friend, and one of the things she told me was that differences in the pigmentation of corneas were, er er er, normal.

The more serious question, I think, has to do with the way in which implants are manufactured, the materials that are used, the testing that is done. We cannot assume that all implants are chromatically neutral, as ideally they would be.

Interesting about the color impressions. Perhaps our cornea pigmentation is different. We just learn to see things a certain way. My eye to eye differences could be caused both effects.

Your comment about manufacturing differences is correct. I have been involved in plastics for many years, as an engineer. No matter how careful you work at it, there are variations in plastic molding due to temperature, pressure, moisture and other factors that affect the final product.

I appreciate your comments. 😎

 

[payasam]

This business has serious implications for old expressions in languages. The meanings of all these and so many others will change: "snow white", "sky blue", "in the pink of health", "in a blue funk", "blood red"....

[EDIT] The Corgi's name wouldn't be Spider, would it?

 

[Dougg]

Interesting issue... I've had implants in both eyes, done a year apart but in the same facility by the same doctor. In looking at the world anew after the first implant, my experience was the same as Bruce's. And I asked the medical personnel about it in the recovery room. They said that the cataract gets a stronger yellow cast as it develops. Certainly was a noticeable difference for me, but I too took the new as "correct" and the developing cataract in the other eye as "too yellow".

Now I seldom use glasses for using the computer or a camera, so I have an easier time seeing the outer edges of the viewfinder. Also, since I had the surgery on the right eye first, the worsening vision in my left eye forced me to switch from left-eyed to right-eyed shooting. I'm sorta "ambi-eyed" now but use the right mostly out of recently-developed habit.

 

[rxmd]

How about focusing? Are they fix-focus implants? What distances did you have them set to, and how do you manage using a camera with them?

Philipp

 

[Dougg]

Yes, these ocular implants are fixed-focus; as the light level drops and the aperture opens up and DoF drops off I tend to put on my glassses... night driving for instance, and reading a menu in the restaurant. The focus distances are different: Arms-length for the left eye and near-infinity for the right. Good for most circumstances, each eye helping the other, and for the first time ever I passed the driver's licence renewal exam without glasses. The right eye's infinity focus makes it better for a camera viewfinder.

 

[payasam]

My implants, fixed focus, are both set so that I need a slight minus correction, cylindrical, for infinity. I can walk about comfortably without spectacles. Focussing my screw Leica is easy because it has correction (a "telescope") built in; and my VIOOH finder also needs no spectacles -- wouldn't take them, actually, for the 35 mm frame. To read the small engraving, though, the left lens in my "photo glasses" is a shade more plus than my reading glasses. I still need to visit my optician to check what the right lens of that pair needs for my SLRs. For the screen of my digicam, of course, correction for near vision is necessary. My "computer glasses" are set to near vision minus half a dioptre in view of working distance. There are now two sorts of implants around which adjust to different distances -- but they are still far from perfect and are frightfully expensive. A photographer who has cataracts dealt with is likely to have needed spectacles for years on account of presbyopia anyway.