Re: M6 & Infra-red

[Joe Berenbaum <joe-b@dircon.co.uk>]

At 20:56 26/05/97 +1000, you wrote:
>the size of the
>affected area is about half the size of the white circle on the blind. I
>think it has to be aperture related because I have never noticed it on
>pictures taken with an apertures larger than f11. This makes me think
>that the edges are diffused enough at larger apertures to be less
>noticeable.
>It really became a problem when I photographed a grove of trees in a
>barren landscape. The trees were in the bottom third of the image area
>and what was meant to be a black sky had a faint "rising moon" effect
>over the trees. Sounds great, but that is not what was there and not
>what I wanted.
>I must point out that I have used less than a dozen rolls in the Leica .
>I cannot use it in the Canon EOS because the DX-code reader or the is
>infra-red and fogs the film!!!  Looks like I'll have to dig out the old
>manual Nikon for IR work.
>
>Does anyone else have any suggestions before I contact Leica?

I've been meaning to use my M6 for black and white IR but haven't done so
yet; I seem to use colur IR in that and b&w IR in a Rollei 35 so far. But
now I'm curious.

Also I'm curious what lens/es you were using when you got this effect.

I have one suggestion; assume the most likely explanation, which IMO is that
the shutter that is leaking IR between exposures and set out to prove or
disprove it by shooting pictures that will (or are likely to) show the
effect on the first half of a film as you did before, and then religiously
use a lenscap between exposures on the remainder of the film whilst
continuing to shoot pictures that you think are likely to show this effect.
If the phenomenon only appears on the first half, you will have some
evidence to suggest that the shutter was leaking IR light.


Joe