Tachihara 4x5 and Kodak HSI Infrared Film

[rguinter]

Greetings everyone:

I just acquired some Kodak HSI Infrared for use in my 4x5 Tachihara field camera. The previous owner advised me that some camera bellows will transmit infrared and fog the film. I was advised to do a test sheet with the dark-slide opened halfway to see if film fogging occurs.

Since I've never used infrared film before I would be interested to hear others' comments on this phenomenon. My Tachihara is about a year old and the bellows of course is light-tight at visible wavelengths.

Thanks to anyone for comments. Cheers,

Bob

[Jim Noel]

You should run the test as suggested. There is no other way to tell if a camera blocks all IR.

[Brian Ellis]

The former owner is right, some camera bellows aren't safe with infrared. Wisners were one such camera IIRC. I used a Tachihara purchased new in 1996 with infrared pretty often and never had a leak. So I'd guess you'll be fine. But fortunately you don't need to rely on my guess, you can do the test and be sure.

[rguinter]

Comments much appreciated. But I would sure hate to waste even 1-sheet of a film that is now quite rare.

Perhaps I will set up my camera as usual and simply wrap the bellows and camera back with an aluminized cloth of some kind. I have several that are advertised as survival cloths for carrying in a survival kit. I have used them under a sleeping bag on frozen ground with good success. They are supposed to be a perfect reflector for infrared.

Just a thought....

Cheers

[Brian Ellis]

Comments much appreciated. But I would sure hate to waste even 1-sheet of a film that is now quite rare.

Perhaps I will set up my camera as usual and simply wrap the bellows and camera back with an aluminized cloth of some kind. I have several that are advertised as survival cloths for carrying in a survival kit. I have used them under a sleeping bag on frozen ground with good success. They are supposed to be a perfect reflector for infrared.

Just a thought....

Cheers

I don't really think you'll have a problem, I never did with my Tachihara. But if wasting one sheet on a test concerns you then make one "real" photograph instead of doing the dark slide test. Process it and see what you get. You'll be able to tell whether you have a light leak by looking at a "real" photograph as well as from that test.

[Jim Michael]

You could build a simple IR detection circuit and use it to test the transmission of the bellows material, e.g. http://calipsooutreach.hamptonu.edu/...to_tran_ir.pdf

[SamReeves]

Dunno about HSI, but you could always be safe and go with the very slow Maco IR if you don't want to fog up your negs.

[rguinter]

Thanks to Jim for the circuit reference. I haven't had my soldering iron out in a while and the circuit is quite simple. I may try that if I run into obvious problems. And ditto to Brian with thoughts about a B&W comparison photo. Would be easy to expose a sheet of TMX of the same scene and see how it compares. Cheers. Bob

[walter23]

Comments much appreciated. But I would sure hate to waste even 1-sheet of a film that is now quite rare.

I agree, this stuff is rare. Why don't you set up a nice shot and take it as a test? If you lose it, chalk it up to a test. If not, you've got a nice sheet out of it.

You can always return to retake the shot if you find the bellows leaks and you need more protection.