[MF3D.FORUM:420] Re: fl/30

["Bill Glickman" <bglick@xxxxxxxx>]

John B / David (or anyone else who knows)

    Yes, that makes sense when the lenses are longer than 80mm, but when
they are shorter, say 43mm, are you saying keep the deviation the same at
2.7 regardless of how much shorter the fl is?    Just making sure I get this
right, I would have doubled the 2.7?  But I am a beginner at this...

Bill G

> >     Thank you for helping out.... so you are saying, in the example you
> >cited, 78mm/150mm, or approx. 1/2, * 2.7 or 1.35, right?  So if I use
this
> >figure (1.35)  in place of 2.7 deviation in John B's formula, you feel
> >it will provide the best 3d base, right?
>
> >      What this actually does, vs. using the same 2.7 at all times is,
> >in the case of the 150mm lens, it cuts the base in half.  It kinda of
makes
> >sense, but I don't have enough experience to know for sure...
>
> I think what David was saying is what Mannle says - keep the deviation
> to no more than 2.7 mm.  So if you double the focal length of the camera
> lenses, you'll have to cut the stereobase in half or double the distance
> to the nearest object.  Nicht wahr?
>
> John B
>