Re: PHOTO-3D digest 1245 auroras

["The Photo-3D List" <photo-3d@xxxxxxxxxxxxxxx>]

I want to correct an error in my last posting.  I got home from the office 
and looked up my exposure notes from the 1966 film project on the aurora. We 
used tri x stock which I believe was rated at 320 or 400 in those years, but 
we pushed it to 6400 stops.  Our exposures times were on the order of two to 
four seconds per frame; and our widest avaiable aperture was f/2.3. 

We had our own motion picture lab and prints were made for projection from 
the original negs.  I believe a high contrast titling print stock was used 
which augmented the contrast between the aurora and the background sky.  
While it diminished detail and shading, it did allow measurement of the 
physical volume of the display.

Regards
Harold


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