Re: Which Viewer for Well-endowed Man?

[P3D Bill Davis <bd3d@xxxxxxxxxxxxx>]

Gabriel wrote:

>
>Bill writes this in regard to my mentioning the Realist type viewers are
>less than 10% larger than the VM viewer. Yes I agree that it is larger
>ultimately but as I mentioned in the original post it's not really
>significant.
>I think the confusion lies in that the focal length of the VM being longer. 

Say what?  Maybe the confusion lies in fractured syntax. :--)

>This gives the impression that
>the image is farther, and consequently smaller. BUT if you do a side by
>side comparision you'll see that this is not the case. There is a way to
>try to verify this by direct comparison of both views. Take the VM with
>5 p mount and look at the right eyepiece with the left eye. At the same
>time view the left lens of the Kodaslide with the right eye with another
>5p in it. Try to overlap the two images and compare the sizes. Hopefully
>you'll see something similiar to what I see. :-)


O.K., I did this with two identical empty cardboard mounts. To make it a bit
more accurate I marked 1 mm increments along the edge of the aperture of the
mount in the KS II.  Carefully following your procedure, I lined up the top
edges of the respective apertures and took careful note of where the lower
edge of the View-Master mount crossed my scale. As near as I could tell, it
crossed at 2.6 to 2.7mm.  Bearing in mind that the aperture height is 23.5
mm, this calculates (by my math) to between 11.1 and 11.5% difference.
Although I had expected something closer to 15%, and while this may be not
really significant to you (you aren't a government worker by any chance, are
you? :--)), to me it is still a very large difference and was evident even
without a side-by-side comparison.  

Now that that is settled (?), can we get back to my original question, which
was:

>Are there any Realist-format viewers available which offer short f.l.
achromats, >internal illumination, focusing capabilities AND separate lens
barrels?

George T., who probably has examined more different 50's-era viewers than
the two of us combined, did not offer me much hope.  Looks like I'll either
have to head for the workshop and build my own, or sell something and
contact Hugo de Wijs.  (Anyone interested in a near-mint Kawasaki 250
two-stroke triple? )

Thanks.

Bill Davis



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