M
P.S. I have verified this with one of my Fuji "super zooms"
-----Original Message-----
From: ADavidhazy [mailto:andpph@xxxxxxx]
Sent: Sunday, April 12, 2009 08:07 AM
To: 'List for Photo/Imaging Educators - Professionals - Students'
Subject: Re: Is this something or nothing?
Herschel, I think the "trial-and-error" (or as you say analogue) way of finding the best rotation point is the most efficient and practical way. The location of the point seems to depend on a number of things and accounting for them all is probably not a simple matter if you don't have information about the internal design of the lens. And even if you do it is not simple! - andy Herschel wrote: > This is interesting. I use the fancy manfrotto QTVR set up with levelling head > and 2-axis displacement sliding arms etc. > I have done some experimentation with different lenses and I think you're on to > something here. > > I must go back and look at the numbers more carefully because when I first > started using it I used a 50mm lens and calculated where the nodal point was, > then used that as a starting position and it wasn't quite right. I attributed > this to errors in my measurements and the fact that lenses for 35mm cameras had > complicated optical arrangements etc. > > But it makes sense to me, geometrically at least, that it's some other (Exit > pupil point?) place. How do you calculate the position of the exit pupil... is > it the aperture? I used the broomstick experiment that Walter talked about... > which gave me what I wanted in a rather "Analogue" way
