Re: Kodak HIE and #87C

["Willem-Jan Markerink" <w.j.markerink@xxxxx>]

On 20 Jul 99 at 13:59, Tolga Yayalar wrote:

> Hi everybody,
> I've been using #25 filter quiet while but recently I purchased kodak's 87C
> filter. I've just developed my first roll, I was shocked with the results. I
> had shot the roll on a sunny day with some clouds. In some shots I also used
> #25 filter  just to be able to compare later. The ones that I shot with 87C
> are almost completely black, I can see the image but they are so dense that
> edges of the film is effected too. But the ones that I shot with #25 are
> just as I expected. I used 400iso when #25 is atteched to the lens and 12
> iso with the #87C. Kodak and most people suggest 10 iso with the 87C but my
> camera has 12 minumum. I also developed in rodinal 1+50 12min@xxx This
> combination gave me good results with #25 at 400 iso. I wonder where I did
> wrong. Is it the film speed or developement? I know IR light is very
> unpredictable but what is the filter factor of 87C? Any ideas and
> suggestions would help a lot. Thanks

Simply apply the Sunny Sixteen Rule: 

1/ASA seconds @ f16 on a bright sunny day.

HIE with #87C is 12 ASA, so this becomes 1/12s @ f16, or 1/60 @ f8.
Your bracket range then becomes 1/60s @ f5.6-11, or 1/250s @ f2.8-5.6 
with teles (I wish Canon would finally introduce a 200mm/f2.8 image 
stabilisation lens!....:-))

For #25 red all the above reads 2 stops faster (50ASA).



 

--                 
Bye,

Willem-Jan Markerink


      The desire to understand 
is sometimes far less intelligent than
     the inability to understand


<w.j.markerink@xxxxx>
[note: 'a-one' & 'en-el'!]
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