[MF3D.FORUM:622] Re: as reguards to using 43mm or 80mmlenses

["Don Lopp" <dlopp@xxxxxxxxxxxxxxx>]

To Oleg
>From my limmitted experience I figure the base using a deviation of about
1mm my math capabilities are quite limmitted, Iam using expieriance as my
guide Don----- Original Message -----
From: "Oleg Vorobyoff" <olegv@xxxxxxxxxxxxx>
To: "Medium Format 3D Photography" <MF3D.Forum@xxxxxxxxxxxxx>
Sent: Monday, May 29, 2000 5:54 AM
Subject: [MF3D.FORUM:604] Re: as reguards to using 43mm or 80mmlenses


> Don Lopp wrote:
>
> >I don't remember whether or not you mentioned how close the nearest
> >thing was in your photos was, but with a 6 inch base for the 43mm
> >should be about 20 feet and about 36 feet for the 80 mm lenses more
>
> >or less depending on how the verticles are arranged.
>
> Don, what calculation method are you using?  I get much smaller distances:
about
> 8 feet for the 43mm lens and 15 feet for the 80mm lens.  Example for the
43mm
> lens, using John B's formula:
>
> Base = 0.0025*(100*2.57/(100-2.57))*(1/.043-1/6) = 0.152m or 6 inches
>
> In the above I adjusted near point by trial and error until I got the
0.152m
> base we sought.  Near point came out 2.57m or 8.43 feet.  Other
assumptions made
> in the calculation were:
>   On film deviation: 0.0025m
>   Far point: 100m
>   Focus point: 6m
>
> Oleg Vorobyoff
>
>
>
>
>