I absolutley agree with DMcD regards bifovcals and flying. Multifocals are a dead loss with great reduction in peripheral acuity (not vision). I find the wider field of accurate vision available to me with bifocals at work essential for watching my F/0s panel.
I have the split right on the instrument panel top level which also just happens to suit gliders. Ron On 23 August 2013 09:03, DMcD <slutsw...@gmail.com> wrote: > Hello Bernie, > > I had eye surgery a couple of years ago for early-ish onset cataracts. > I said to the surgeon, does that mean I won't be able to focus and he > said, "You have not been able to focus for years." The fact is that > for people over 40, your focussing performance degrades like falling > off a cliff to the point where after 50, you can't focus worth the > mention. > > Getting any eye surgery done is terrifying, whatever they say and not > to be taken lightly. However the results may be worthwhile. I have > never met anyone who has had laser surgery who was not back needing > glasses or surgery some years later. My cataracts were marginal but I > went for surgery because the mild double vision was worrying. The > results were spectacular with probably 15:20 vision as a result. > > I wear multi-focal lenses now. Why? Because I still cannot focus and > need glasses. I can wear off the shelf sunnies but they won't allow me > to read that well… though oddly, I can read a menu better than most > middle aged people even though my bionic focus is set to infinity. > > For flying gliders, you mainly need two focus ranges. One is close > within the cockpit which ranges from 400mm to about a metre and the > other is infinity. If this is true for you, then why bother with > multi-focal lenses when bifocals will do the job better and for less > money? I say better because a bifocal lens covers a wider field of > view with the same focus and has none of the vexing distortion which > is a guaranteed result of almost all multi-focal lenses. Running > downhill or down steps is really difficult with multi-focal lenses > because the focal position in the lens means you have your head at the > wrong angle. > > I have worn bifocals flying for some time, made specially to suit. I > got the frames and sat in the glider and car and drew the top of the > instrument panel on the lenses and the bifocal split is made for this > and it works perfectly. Our local optometrist will dye the lenses to > whatever colour you want and even add or reduce the tint for optimum > results. > > Something worth looking at are Barz sunnies. > > http://barzoptics.com > > They are an Australian company who have thought a little more than > most about bifocal sunnies. You can get a range with things like > polarised lenses with a non-polarised bifocal/ > > _______________________________________________ > Aus-soaring mailing list > Aus-soaring@lists.internode.on.net > To check or change subscription details, visit: > http://lists.internode.on.net/mailman/listinfo/aus-soaring >
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