P3D Red Button, K2 compared

[Arthur Payson <APayson@xxxxxxxxxxxxxx>]

In all the recent discussions comparing viewer optics, I am surprised that
no one has brought up the lack of contrast inherent in Red Button viewers.
I have been using K2s for many years, and recently examined a number of Red
Buttons.  In all cases the Red Button displayed a hazy image, with very low
contrast and poor color saturation.  It is true that the Red Button is
sharper than the K2 around the field edge, but the overall effect of the
image is far less dramatic, in my opinion, in the Red Button.

Dr. T attributes this "fogging" to the cement used when assembling the
doublet lenses used in the Red Button, and has indicated that this problem
is more pronounced in some viewers than in others.  I have seen the fine
job Dr. T does modifying the Red Button for 8-p, and indeed the image is
relatively sharp out to the corners, but this lack of contrast I find
distracting.

I think the sharper edge makes the Red Button a good viewer for checking
stereo window placement, but for impressing your friends with a great
stereo image, the K2s good contrast and color saturation delivers more of
the "wow" factor.

Arthur Payson



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