InfraRed filters?

[Daniel_Buck]

I'm curious, I've used a Hoya R72 on my digital camera and got quite nice infra-red images. Can the same be done with B&W film? (Tri-x 320 in particular). I really enjoy infra-red images, and I'd like to have some nice 8x10 negatives in IR! Is this possible with out going to film that is specifically infrared?

If this is possible on tri-x, how would I go about calculating the exposure? on the digital, I just shot long shutter speeds till I got an exposure I liked. Not really an option on film I guess.

[jetcode]

I'm curious, I've used a Hoya R72 on my digital camera and got quite nice infra-red images. Can the same be done with B&W film? (Tri-x 320 in particular). I really enjoy infra-red images, and I'd like to have some nice 8x10 negatives in IR! Is this possible with out going to film that is specifically infrared?

If this is possible on tri-x, how would I go about calculating the exposure? on the digital, I just shot long shutter speeds till I got an exposure I liked. Not really an option on film I guess.

The short answer is that Tri-x emulsion is NOT light sensitive in the near infra-red region of the spectrum. Specialized infra-red film is sensitized in the near infra-red and visible spectrums. I used to Shoot Kodak HIE in 4x5 sheets using a #25 red to get a taste of both spectrums. The choices for infra-red film have all but vanished.

Since digital sensors sample available light from a wider spectrum than desired there are special filters to shunt the infra-red and UV spectrums. These filters can be bypassed on some digital cameras though from what I understand doing so is a permanent fix.

I liked your Malibu sunset B/W on a different thread. Great image.

Joe

[Daniel_Buck]

What films are still available that are sensitive to IR? Can any of them be developed with the usual B&W developing methods? (Say, HC110 and others?) or is it a specialized process? I'd like to get something that doesn't see much of the visible light, mostly IR, in B&W.

[Chauncey Walden]

Check Freestyle. They carry Efke/Maco, Rollei, and Ilford SFX. Standard developers. Here's some good info: http://www.pauck.de/marco/photo/infrared/comparison_of_films/comparison_of_films.html

[Ron Marshall]

What films are still available that are sensitive to IR? Can any of them be developed with the usual B&W developing methods? (Say, HC110 and others?) or is it a specialized process? I'd like to get something that doesn't see much of the visible light, mostly IR, in B&W.

http://www.freestylephoto.biz/sc_prod.php?cat_id=&pid=1000001797

[gregstidham]

Tri-X with R72 filter will yield blank sheets. I've already tried it once for the heck of it years ago. Tri-X does not record the near IR spectrum.

I shoot Efke IR820 4x5 with an R72 and it gives a nice subtle IR wood effect. It is the only emulsion I am shooting at the moment. Rate the film at ISO 6, HC110 DilB @ 20c for 8m - 10m depending of the lighting conditions of the day. IR exposures fluctuate depending of the temperature of the light. R72 filter on Efke IR 820 will record between 720nm and 820nm.

I load in a Harrison tent and use standard fidelity holders. I have found the film requires a very tiny focus correction if you are using old barrel lenses like my Cooke Series II 8", but no correction is needed if you are using newer lenses like my Sironar N. I tend to shoot wide open (f4.5, f5.6), so if you stop down, your focus will need no correction. You should test your own lenses to get a feel if you need any focus correction. Even when I don't correct the focus on my Cooke, the photographs are still quite acceptable for my standards.

Good luck

[Daniel_Buck]

I shoot Efke IR820 4x5 with an R72 and it gives a nice subtle IR wood effect.
Thanks for the info Greg! When you say subtle IR effect, do you have any scans of what it looks like? I'm looking for something a bit more than subtle.

[gregstidham]

Thanks for the info Greg! When you say subtle IR effect, do you have any scans of what it looks like? I'm looking for something a bit more than subtle.
I don't have any work scanned or copyright registered yet, so I can't post it. Digital Truth has some comparisons that might work for you. I think I saw a sample here once, so you might try a search.

When I say subtle, I mean it will not compare to HIE which recorded well over 900nm. The effect with Ir820 is still nice and offers a good wood effect. I'm happy with it.

[Chauncey Walden]

Daniel, check the link I posted. There are examples of all the films with various filters.

[Daniel_Buck]

Chauncey, yes I'm looking at that, thank you :-) I asked Greg because I didn't see the Efke film listed on that site. The Kodak High Speed Infrared on that site looks like what I'm looking for. Have to look around and see if it's still in production.

[Laszlo]

Daniel:

A few examples with Maco 820 / Hoya 72:
Palo Alto (http://www.vassar.info/gallery/photo.php?photo=457&exhibition=1&ee_lang=eng&u=21620,25), CA, Budapest (http://www.vassar.info/gallery/photo.php?photo=1102&exhibition=1&ee_lang=eng&u=22538,17), Hungary, Phoenix (http://www.vassar.info/gallery/photo.php?size=3&photo=3240&offset=1&u=21520), AZ, another Palo Alto (http://www.vassar.info/gallery/photo.php?size=3&photo=2712&offset=4&u=21520), CA

[Daniel_Buck]

Thanks for the examples Laszlo, appreciate it! Those last two are what I like, nice :-) Much more than what a deep red filter does on regular pan film!

[Chauncey Walden]

This link from Freestyle has some good comparisons also:
http://www.digitaltruth.com/store/product_tests2/index.php

[Laszlo]

One problem I had w/ Maco IR was guessing EI.

I started with 3, 4 or 6 based on the manufacturer info and the images tended to be variably exposed, often very thin.

Then there is the issue of uneven IR level during the day.

What sensitivity are you guys using? Do you adjust for noon vs dawn/dusk (I assume there is more IR at noon even for the same EV)?