Am 12.01.2016 um 20:52 schrieb Mike Horvath:
> On 1/12/2016 2:17 PM, clipka wrote:
>> By /adding/ a "look_at" statement? ;)
>>
>> For starters you might get away ok without look_at.
>>
>> What you really need to do is translate the camera a bit to the left
>> (for the
>> left eye) or the right (for the right eye) -- which is actually a deal
>> easier if
>> you don't use look_at, because with that statement you'd have to
>> compute your
>> effective left/right axis "manually".
> 
> Okay, but I was thinking that rotating by a small amount would be
> better. Otherwise the point of interest gets translated too. Should I
> use real-world measurements for the distance between the "eyes"?
> 
>>>
>>> Also, is there a particular angle of view I should be aiming for?
>>
>> That depends on the (apparent) angle at which the image will be
>> visible using
>> that contraption.
> 
> I don't understand what you mean. By angle of view I mean the camera
> angle. Is there some natural angle that is most like human vision?

It all depends on the contraption you use, and the size you print the
images at.

Let's forget about the stereoscope for a moment, and take a look at the
situation for a normal computer display. Suppose your display is WIDTH
cm wide horizontally, and you view it from a distance of DIST cm. The
display will occupy a certain portion of your field of vision, namely
ALPHA degrees in horizontally, where

    tan (ALPHA/2) = (WIDTH/2) / DIST

Now for any image you display at full width on that computer display,
and view under the given parameters, the "natural angle that is most
like human vision" is exactly ALPHA.


With a stereoscope, the situation is more complex, because there are
lenses involved, so the /actual/ WIDTH and DIST parameters are of no use
-- you need to know the /apparent/ WIDTH and DIST, or the apparent ALPHA
itself. But the principle is always the same: The angle you want to
specify in POV-Ray is the horizontal angle that the image effectively
occupies in your field of view.

The lens also affects what camera type you should choose. With the
computer display, you want the default perspective camera; with the
spectroscope, you may want a more fisheye-like projection.
ultra_wide_angle projection may be ok for your purposes.

Post a reply to this message