Re: Holmes viewers

[P3D John Weiler <jweiler@xxxxxxx>]

George Themelis says:

>>Once you get used to using achromatic card viewers, it is very
>>difficult to go back to the chromatic aberration of simple lenses.

Amen to that!  I have one of Alan Lewis' achromatic viewers and can
second George's recommendation.  It's amazing how much fine detail in a
good stereoview is obscured by the chromatic aberration of the typical
single-lens glass or plastic stereoscope.  You think you're still
seeing all the detail in the view, but while the color fringing may not
be evident everywhere in the image because the blue and yellow fringing
from various parts of the image sometimes superimpose and thus cancel
out, the loss of resolution is definitely there as revealed by a
side-by-side comparison with an achromatic viewer.

Of course free-viewing eliminates this problem, but the major downside
of free-viewing is the significantly smaller apparent image compared to
the near-ortho-sized image from a proper stereoscope.  I can free-view
35mm stereo slides, but why would I want to?  Free-viewers of
stereoviews miss out on seeing the proper stereo effect as intended by
the photographer and all the detail present in a quality view.

John Weiler
Columbus OH


------------------------------