Re: BWIR Exposure

[George L Smyth <GLSmyth@xxxxxxx>]

Lovell wrote:
> 
> Greetings all,
> 
> Shortly I am going to experiment with shooting my first IR film, and
> will probably choose the Ilford SFX200 as an introduction (or maybe I
> should just take a full blown IR film and see what images eventuate!)

If you're going to do it, I would suggest doing it.  My feelings are
that SFX200 is not worth your bother, as it barely touches the IR
spectrum.  If it is winter where you are, you will see considerably less
difference from panchromatic film than you will in the middle of the day
in the summer.  It's a good time to begin and chart how the
characteristics of this film seem to change as the seasons change.

> and have a question regarding the correct exposure. If vegetative matter
> and masonry surfaces are going to have a higher reflectance (compared to
> standard BW film) then I need to underexpose, but by how much?  0.5
> stop, 1 stop etc. obviously experimenting is the way to go but if
> anybody can provide some recommendations then I should hopefully produce
> a better output from my first roll.

Assuming that you are going to shoot the real thing (HIE) <g>, I would
suggest that you place a #25 filter over your lens, set your meter to
EI250, meter TTF (through the filter), and fire away.  Take as many
notes on each exposure as you feel relevant and bracket a stop on each
side.  With the resultant negatives and your notes, you will quickly get
a feel for what the film can do.

I would highly recommend reading the IR FAQ (I have a pointer to it on
my Web site), as it will answer many common questions you will have.

Cheers -

george

-- 
 Handmade Photographic Images     
  http://www2.ari.net/glsmyth/

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