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Coping with less-than-perfect vision
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Bifocals for Bell Ringers Coping with less-than-perfect vision |
I am, by profession, an optometrist, and I would like to pass along some information to those of you with ringers over the age of 50. The eye, as most of you all know, loses the ability to focus at near gradually beginning about age 40-45. By age 50, most need some help at "intermediate" distances, ie: bell scores. The score will not be clear through the top portion of their prescription so you will see them leaning in with their chins raised up looking through the bottom of the lens (getting into range of the bifocal segment). This is even more difficult in "no-line" bifocals since the change is gradual and there is usually some searching (up and down movement of the head) involved.
If your ringers in this predicament are willing to spend the $ for a separate pair of "bell glasses", have them stand in their normal ringing position. Measure from their eyes to the music in inches (centimeters if you can, but no problem if you can't). Then have them ask their optometrist/ophthalmologist to write a prescription with the top part being their normal distance prescription and the bottom part in a (technical lingo approaching) "flat-top 35 segment set at mid-pupil" with the power to be determined by your measurement (s/he'll know how to convert this into dioptric power). The reason you want to have the segment set so HIGH!!! is because the person is usually in a slight chin-depressed posture while ringing and you want the intermediate segment easily accessible (ie - no head movement ). Then when they need to look up, they can see the director clearly through the top portion.
I have placed all of my presbyopes (latin translation: old eyes ;> ) into this arrangement and they all LOVE it. It makes playing so much more easy since they don't have to worry about being able to see. (No more excuses!!)
ALSO.....if you truly have someone with reduced eyesight because of disease (ie cataracts, macular degeneration, etc) get them LOTS of light. One of my ringers has two halogen lights on her notebook.
Written by:
Dr. Vicky Vandervort
Paradox616@aol.com
Omaha Eye Institute
St. Mark Lutheran Church handbell director
20 May 1997
Archived original can be found at: Re: Eyesight and handbells
Qualifications to comment on subject: (a) Father is an opthalmologist (and former GP) who at age 88+ still sees patients two mornings a week. (The rest of the time he's working in his garden, so he's in better shape than I am!) (b) I am severely myopic (20/800 uncorrected, 20/18 corrected), have worn glasses since before I entered school, have survived the mid-life change of vision, and am still ringing in two handbell choirs (one church, one community/auditioned).
Vision definitions:
Persons under the age of 45 who have only simple myopia or simple presbyopia can usually be corrected to 20/20 vision, and then have normal depth of field--from within arm's length to beyond road signs. This depth of field results primarily from the ability of the lens of the eye to adjust; that's analogous to focusing a camera (or camcorder), though the mechanism is vastly different.
At about the age of 45 (in most people), the lens of the eye loses its flexibility (medical term: its "accommodation"), and therefore the depth of field shrinks. It is principally the near end of the range which is lost, and this becomes obvious as you have to hold things farther away to read them (i.e., put them within your usable focal range). To compensate for this loss of depth of field, different strengths of corrective lens are required to place the limited depth of field at different distances. At one time, the only way to do this was with different pairs of glasses (e.g., for reading and for driving). Later, bifocals and trifocals came along, eventually with a variety of possibilities for arranging the different segments. Most recently, continuous-focus lenses have become available (under a variety of manufacturers' terminology).
So what does this have to do with ringing? Simply this: If you do not understand what is happening to your eyes (or your ringers'), and the distinctive vision requirements of handbell ringers, then you will not be able to solve your problems, nor help them solve theirs.
All the eye professionals--opthalmologists, oculists and opticians-- are accustomed to patients who are desk workers or otherwise need to have their best focus either where their hands are or out at road-sign distance. They are not used to working with people who need to have their best focus a foot or two beyond the ends of their arms, i.e., on music racks. As in so many other aspects of medicine, a well-informed patient can help the health professional to do a better job. Also, the person who understands the nature of his/her own limitations is better equipped to cope with them.
Personal example (or how I cope): When my eyes lost their accomodation, I switched to progressive focus lenses. I've never worn bifocals, whether segmented or blended. For me, the advantage of _always_ being able to find a _precise_ focus by raising or lowering my head a little has more than offset the disadvantage that I must look directly at something to see it most clearly. Looking to left or right (without turning my head), everything is a bit out of focus. (Other people might weigh these values differently, and come to the opposite conclusion.) As nearsighted as I am, glasses are fairly expensive, as well as being heavy. I simply can't justify the expense of purchasing multiple pairs or the nuisance of carrying them. With handbells, this centerline requirement doesn't bother me, because the music is far enough away that I don't need to turn my head very much to left or right while reading across a page of music. (However, the music rack of a keyboard instrument is much closer, and therefore causes me more difficulty. I've about given up playing keyboard instruments until I can justify buying a pair of single-focus glasses specifically for that purpose.)
On the other hand, a person who never needed glasses until reaching the mid-40s might be well served by multiple pairs of dime-store ready-made reading glasses. They will be inexpensive, light weight, easy to carry, and therefore easy to experiment with. As always, YMMV.
Here's a different point (which camera nuts will already know): Once your eyes lose their accommodation, their depth of field will still vary as the pupils dilate or contract in reaction to available light. The best depth of field occurs with the brightest light. Therefore, it may be that the best thing directors can do for their aging ringers is to put good, adjustable, bright music lights on every stand in every situation where they can make a visible difference in the illumination of the music.
Similarly, it will help the ringers for the director to stand in a well-illuminated spot, if possible.
Finally, the best way to get ringers to watch the director may well be to make sure that each ringer's music is as close as possible to the line between ringer and director. Being continuously in the ringers' near peripheral vision may well be more useful than being only rarely in their direct vision, especially if the director is always out of focus!
This essay is much longer than I wanted it to be, but all these points are tightly interconnected. All must be considered in order to optimize the process of getting information off the printed page and into the mind of the ringer through the sense of vision.
Written by:
Carl Scott Zimmerman, CCP
csz@intecnet.net
Certified Computing Professional (ICCP)
Campanologist
12 Apr 1998
Archived original can be found at: Music vision