Re: [APML] Large Format Question

["Joseph O'Neil" <joneil@multiboard.com>]

>Thanks for this tip; I've been looking for aerial photography lenses
>after seeing how many people are successfully using them.  From what
>I've read, I may have problems with color as some of these lenses
>focus poorly in the blue.  Still, it will be worth a try.  I've
>spotted a couple of Kodak Aero Ektars on Ebay which are f/2.5 and
>Surplus Shed has 6" f/6.3 Metrogon for $35.  If I can get the faster
>lens, I'll try that....

         If you go to the Kodak web site and look up aerial films:
http://www.kodak.com/cgi-bin/webCatalog.pl?category=Aerial+Films

         You will notice many of the films are infra-red.  however, even 
the ones that are not, such as the areial versions of tri-x and plus-x, you 
will notice on the data sheets, that they are all extended red sensitive, 
not at all unlike the spectral response of tech pan. You have to click 
seperately on the spectral curve diagram, however, spectral responsie is 
good to 690 nm, and drops off after 700.  Regular consumer trix- & plus-x 
is good to - oh, form memory here, 640nm or so?

         On a tangent, one begins to wonder if this stuff would make good 
astro-photo film.  I ahve not idea.  usually areial film comes in zillion 
foot long rolls, of 70mm size, which I am told, but never have seen it 
myself, can be used in medium format cameras with a specialty back.

         Anyhow, back to the lenses, since most aerial camera lenses are 
usually made to be used for red sensitive or evne infra-re films, you will 
find the lenses are made to be used for red light having the best focus, 
and blue - dependign on the lens - being all shot to hell.  This is 
exspecially true for WW2 and Korean war era lenses, you just have to use 
them with a yellow filter, or red, even daytime use.  So, great lenses for 
tech pan, but would not reccomend them for E200.

         Newer lenses however are probally much better colour corrected.
joe



http://www.oneilphoto.on.ca
http://www.multiboard.com/~joneil
"Una salus victus nullam sperare salutem"


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