Was wondering if anyone has a proven design for a 70mm to 120 size film
cutter they would be willing to share. At the present time I believe there are
two folks who currently cut down 70mm infrared film to 120 size for resale.
I think that just to try out the film, $12.00 per roll wouldn't be bad. If you were
someone who really enjoyed shooting infrared in medium format, then I would think the only cost effective means would be to construct your own film cutter.
I did try film from one of the folks who advertises on the web. This was a cut down version of the Kodak 70mm to 120 and re-spooled. The problem I ran into was that the cutter design required pulling the film across a knife edge. I ran into long scratches on the film. I think the perfect design would have the film stationary and a moving cutter wheel running the specific length of 120 format film. Since Kodak dropped the 4x5 format in infrared, this cut down stuff is my only means of filling my infrared appetite! Thank you!
Rick, Have you tried shooting the Konica 750 Infrared Black and white in 120 size rolls? I know it's not true infrared being that it is down in the 750nm range but my personal experience has been good with it. I rated the film at ISO 32 and developed it in D-76 for 6 minutes at 68 degrees per Konica's instructions.
The film isn't as dramatic as the Kodak infrared aero film or the 4x5 but the Konica film is a dream to load and process. It has some pretty tight grain patterns so blowups are no problem. If you are interested, I still have some in my fridge that is dated March 2003 that I will let go pretty cheap.
I was shooting the Konica through a 25a Red filter,a 29a might be a little better. Jim
Does your 4x5" camera have a Graflok back? It's not to hard to find 70mm Graflex and other backs to fit a 4x5" Graflok, and Hewes makes reels and tanks for 70mm rolls.
</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (Aggie @ Jan 24 2003, 06:26 PM)</td></tr><tr><td id='QUOTE'>try the new maco film,,,it comes in 4X5 format for the infrared. But you need a darker red filter in the 89 range</td></tr></table><span class='postcolor'>
I've been "wringing out" MACO 820 for a while now ... Rumor has it that Konica has discontinued 750.
The 89 series filters have one drawback - they do not transmit much visible light, so, unless one uses a rangefinder, it is fairly necessary to use a tripod, compose without the filter, install it and then expose. Come to think of it, less of a problem - not that far from the ordinary - with a view camera.
Konica 750 has a "bi-modal" spectral sensitivity - with the Infra - red peak centered at 750 nanometers; so the usual #25 would cut off most of the non-infrared light. From what I've seen, there wasn't a lot to gained from a #29 or #87 - #89 filter.
I'm extrapolating - read: guessing - that the same will apply to MACO 820 - but a lot depends on one's individual "taste". Stay tuned.