Re: IR with no direct sunlight

["David J. Romano" <romano@xxxxxxxx>]

Robert,
Infrared film really functions no different than any other film. Just as with
regular film, photos taken in direct sunlight will have more contrast. With IR
film this is still true, but with a more exaggerated effect. If you were to
photograph with IR film on a bright sunny day, but in the shade, you would get
pretty much the same effect as if it were an overcast day.  Since shorter
wavelengths scatter more, areas in the shade are relatively blue, with very
little IR.  This is one of the reasons why, in general, images on IR film are
contrastier that with regular film, and why stronger filtration creates more
contrast: because the shadows are deeper. Longer wavelength IR light scatters
much less than visible light.

Keep in mind the zone system: Expose for the shadows, develop for the
highlights. If you photograph on a cloudy day with IR film and develop the same
way as if it were a sunny day, the images will have low contrast. There will
less "IR effect", even though all of the objects in the scene still have the
same IR reflectivity. Try changing the development time to get the degree of
contrast you need for one of your average scenes. Then try the same thing for a
scene on a cloudy day. One nice thing about cloudy days is that the images tend
to be easier to print and there is often a really nice separation of values in
the clouds which can make a drab day look dramatic.

Changing light conditions makes exposure and development more tricky, but more
fun.  Personally, I prefer to underdevelop a little to prevent the specular
highlights, the ones in direct sun, from blocking up. Then I print on grade 3 or
3 1/2 paper to get the contrast back. It is extremely rare for me to make a
straight print from an IR negative. There is always some dodging and burning,
often using mulitple filter grades in the same print.

Dave



Stan Patz wrote:

> >I accidently deleted a message where someone told me that there is no
> > >necessity
> >to have bright sunlight in order to shoot IR photos. Can anyone tell >me
> >more
> >about his/her experiences under those conditions, some links with >photos
> >would
> >be great, too.
>
>

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