Re: [photo-3d] Re: Next step from Realist?

[Project3D@xxxxxxx]

In a message dated 6/14/00 HWADE@xxxxxxxx quoted pd@xxx with:

<<> but I don't like having to guess the distance all the time to set 
 the focus.
 > 
 > I'm wondering if a Belplasca would be suitable as a kind of "wider 
 > Realist".  Any thoughts on that?>>

and then went on with
 
<< About 6 months ago I moved my main camera from a Realist to a 
 Belplasca. I'm pretty happy with it, although it won't solve your 
 guessing the distance problem as it has no rangefinder. I've wondered 
 about an add-on rf that slips in the hot shoe, but in the meantime 
 I've gotten pretty handy with the hyperfocal table.>>

Which makes me wonder if either have grasped one of the fundamentals of 
stereo at "normal distances" (i.e  greater than 6 feet or so). 

This is that it is desirable for all normal purposes (in other words "unless 
you have a good reason to do otherwise") to have everything in the scene 
sharp.

So, unless you have a very good grasp of optics, it's much better to accept 
the manufacturer's depth of field calculations - and use their depth of field 
scale. But in my case, I always give myself an extra f-stop "insurance". I 
use the DOF setting for a stop larger than I'm using. As a result, I never 
have to estimate exact distances - so long as the closest object is further 
than about 6 feet, and my f-stop is smaller than f11 on my Belplasca...

Bob Aldridge