Re: IR spherical panorama

[Otto Giesenfeld <otto.giesenfeld@xxxxxxxxxxxx>]

--Ben Kreunen <ben@xxxxxxxxxxxxxxxxxxxxxxx> wrote:

> One problem that I have found though is that I was getting some 
> considerable light fall off towards the edge of the images.  I'm shooting 
> with an 8mm circular fisheye, one of the benefits of which for this sort
> of  work is that there is no light fall off with normal films. With IR
> film  however, it appears to be quite pronounced.   The sharpness across
--
> Film was Konica IR, stupidly shot handheld as I was testing a new method
> of  aligning the camera. (1/8sec @ f4, hence some of the blur) I've added
--
> Sigma, manual focus f4..  only a #25 (internal filter).

Have you done any of your non-IR spherical panoramas at full aperture? (One
might think that it would seldom be needed, given better film speed and
less filtration.) If not, the lens may simply have some light fall-off at
f/4. Which may have gone unnoticed in any pictures, IR or non-IR, you have
taken for purposes other than spherical panoramas.

Best regards,

Otto Giesenfeld
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