Re: Effective FL after correcting for myopia

[P3D Michael Kersenbrock <michaelk@xxxxxxxxxxx>]

> I did the calculation for how much you run the lenses
> in if you're myopic and posted it to P3D some time back.
> Even for severe myopia (-6?), it was surprising how little

"-6" is severe?  Oh-oh....  My contacts are only a little weaker than 
that (-5), but I understand that glasses have to be a stronger because
the lenses are further away from my eye.  I took their word for it.

I find the viewer focus adjustment point tremendously different 
between wearing my contacts and without.

Most viewers I've used are *just* in focus (without my glasses or 
contacts) at the dead-end of focus knob travel, or close to
that point.  This includes the Red Button, the achromat green ST-63,
and a couple others.  Back when my wife and I used only one viewer to
view slides, the focus knob was being given a real workout.  That
was the primary reason to get a second red-button.  :-)

So maybe that's a calibration point?

Mike K.

P.S. - The viewmaster model 'd' has a bit less range.  At the "end" of
       it's focus range, I still want to turn it a *bit* further
       (w/o contacts)!



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