Re: Optical advice

[Joe Wilensky]

Just about all camera viewfinders are set up so that your eye thinks 
the focusing screen or framelines are about one or two meters away, 
which is a distance at which most people can focus comfortably for 
long periods without eyestrain, etc. I think the -1.0 diopter built 
into the viewfinder is what most people need to see the viewfinder 
easily at that "virtual" distance.

I think a viewfinder eyepiece with a 0.0 diopter would be flat glass 
-- no correction at all.

Does anyone else have better information on this?

Joe


I guess I must be stupid, but I still don't get it. According to my
optician a 'normal sighted' person should dioptre 0, and glasses should
correct defects of vision to that 'zero-level'.
Why then put -diopters into the viewfinder?



I think most of the Pentax cameras have about a -1.0 diopter
viewfinder eyepiece (I remember that some of them might be -0.8). I
don't think it's unusual, isn't it so that a 20/20 eye can better
focus on the viewfinder screen by making it seem like it's about a
meter away?
I think it's only confusing with some camera brands when you buy the
correction eyepieces, some are marked for the corrective power of the
diopter correction, but some take into consideration what the
correction will be when put on the already -1.0 viewfinder eyepiece.
Putting on a +1.0 eyepiece would bring it to 0.0, but that's not
necessarily the ideal, although it may be for your eye.
Joe


The ME-super has - for some strange reason - a -1.0 diopter eyepiece. Bit
of a problem when using glasses. Would it be a solution to put on a +1.0
correction eyepiece?
Peter Smekal
Uppsala, Sweden
[EMAIL PROTECTED]


Peter Smekal
Uppsala, Sweden
[EMAIL PROTECTED]