Mailinglist Archives:
Infrared
Panorama
Photo-3D
Tech-3D
Sell-3D
MF3D
|
|
Notice |
This mailinglist archive is frozen since May 2001, i.e. it will stay online but will not be updated.
|
|
[photo-3d] Re: focus and convergence
- From: "Chuck Holzner" <cfholzner@xxxxxxxx>
- Subject: [photo-3d] Re: focus and convergence
- Date: Sat, 14 Oct 2000 14:04:25 -0000
I took a stereo picture of the family pet and mounted the left and
right prints in a double picture frame with a center to center
spacing of 52MM. I took the time to set the window properly and get
the two photos aligned vertically. I had no problem free viewing the
picture(s). The spacing was comfortably closer then my eye spacing
and with my glasses on I could focus on the prints with ease.
My son, who is 25, has good 20/20, can see far and up close without
glasses, could not free view the picture. I checked and rechecked
alignment, rotation and window and kept trying to get him to see the
depth with no success. I then figured that he may have his
convergence and focus linked and tried something else: I had him put
on my reading glasses and try again. It worked.
His eyes thought he was looking at a distance but I had caused them
to focus close so his convergence then matched the focus.
Us guys with old eyes can't focus over great depths and so nature has
decoupled the convergence and focus and we learn to focus by tilting
out head to position the glasses. Those with young eyes still have
the coupling hooked up.
It is not a "hard link" that cannot be broken, it is a softer link
under program control by the brain in our head. When we have to
override our brain the head starts to hurt.
Chuck
One good test is worth a 1,000 expert opinions.
|