Re: PHOTO-3D digest 2181

[P3D Ronald J Beck <rbeck@xxxxxxxxxxxxxxxxxx>]

In digest 2181, Peter Homer <P.J.Homer@xxxxxxxxxxxxxxxxx says...
>  so I closed one eye and then the other and realised there was a 
> slight difference in parralax between the two of about 1/2 of 1/10 
> millimetre and my brain was alternately selecting one view and then 
> the other. This was using a Watson system 70 with one objective. 
> Trying other magnifications I found the difference decreased with 
> higher magnifications and was less than the 1/30 rule would suggest 
> so I thought the actual stereo effect might be unnoticeable . Trying 
> the anaglyph method again I found I got a stereo effect using 
> relatively large specimens with no coverslip to flatten them and when 
> I removed the filters it was still there and I thought at first the 
> filters had no effect but I since decided they do improve the effect 
> as does the crossed polaroids method I have tried since. 

These comments confuse me.  You're using a bi-ocular microscope (a 
microscope with one element & two eyepieces) right?  Or is it a bin-ocular 
microscope (a microscope with two elements and two eyepieces.

Regardless of the microscope, as long as it has two eyepieces it seems to 
me that using either anaglyph or polarized lenses over the eyepieces is 
unnecessary.  Both techniques are used to separate the left and right 
pairs of a single image.  In anaglyph, the red lens is used so the left 
eye only sees the image outlined in blue and the blue/green lens over the 
right eye only sees the image outlined in red.  Thus you view a stereo 
pair from a single image.

The microscope is already separating the single image into a left & right 
pair simply by looking into the eyepiece.  So you shouldn't see any 
greater (or less) depth simply by placing the red & blue filters over the 
eyepiece.

Does this make sense?  Am I way off base here in my understanding?  I'm 
not disputing that it may be possible to see 3D via a bi-ocular microscope 
given that the single element is big enough to provide a slight left-right 
separation while viewing.  I just don't think putting anaglyph or 
polarized filters on the eyepieces is going to do it.

Ron



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