P3D Reply by Golden on Zooms

["Dr. George A. Themelis" <DrT-3d@xxxxxxxxxxxxxxxxxxxxxxxxxxx>]

I am forwarding this message that did not go through...

Subject: P3D Re: Anyone use twin Zoom lenses for 3D photography?

Rolland...
Twin zoom is fine...but you better have the lenses matched
well..otherwise you will be wasting a lot of film.  Matching lenses is
necessary...since you can take ten of the same lenses off the
shelf...same model...yet they each may have varaiances.  So the practice
of lens matching begins.  With FIXED lenses....its not as hard...as you
would just set the F stops the same...and focus each lens....but getting
zoom function to match is not that easy...requires skill and certain
tools to get the two lense tracking a close as possible. The same
applies for projection of sterewo...the lenses have to be matched as
best possible.
Macthin zoom sets by Pentax, Richoh, Tokina, Soligor, Cosena and
Zeiss...thats what RBT does with their X2V2 (new),X3,X4 and 109 twin
zoom lens systems...see them at:  

http://www.stereoscopy.com/3d-concepts

Regar-d-d-d-s
Jon Golden



------------------------------