That's an amazing image, Ralf. I feel inspired. I'll source a #87 filter
and give my dormant K110D a whirl as a dedicated IR camera.
Alan C
On 13-Jul-23 10:12 AM, Ralf R Radermacher wrote:
Am 13.07.23 um 01:59 schrieb Larry Colen:
You'll need to focus based on the live view, which is what the sensor
sees, either that or manually focus based ton the distance scale and
the little red dot that shows the IR focus point.
Maybe even a little beyond the red dot which is calibrated for an IR
wavelength of around 750 nm corresponding to the usual near-infrared
film stock like Ilford SFX200 or Konica 750. The infrared sensitivity of
a DSLR sensor extends way beyond that, well into the 800's, shifting the
focus point even more.
And don't try to step down beyond f8 to gain more DOF. Aperture
diffraction at IR sets in a lot sooner than with visible light.
I've been using a #87 gelatine filter on my unmodified *istDS. This
filter is almost completely impervious to visible light.
Here's an example:
https://www.fotocommunity.com/photo/la-bistade-fotoralfbe/32223101
Ralf
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Ralf R. Radermacher - Köln/Cologne, Germany
Blog : http://the-real-fotoralf.blogspot.com
Audio : http://aporee.org/maps/projects/fotoralf
Fotos : https://www.fotocommunity.de/user_photos/770012
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