Chamonix Camera and IR film

[evan clarke]

I just got some Efke IR820 in 11x14 and made my first two test sheets. Sadly, the bellows on this wonderful camera isn't IR safe. Has anybody had this bellows issue with cameras and if so, did you come up with a solution?..Evan Clarke

[vinny]

Yup. chamonix's aren't suitable for ir work. At least their 4x5's (the earlier runs of the 45n-1 used different bellows material). Luckily the shen hao bellows which fit the camera perfectly ARE in my case (45n-2). Time to order a bellows from a different company. Chamonix isn't interested in helping, I asked.

[Kirk Gittings]

What is the difference in materials and/or construction that matter for ir?

[Roger Cole]

Interesting to learn since I'm seriously considering getting a 45N-2. Couldn't you just throw an additional cloth over the bellows before you pull the slide?

[Kirk Gittings]

or a tinfoil pyramid :)?

[Roger Cole]

Your IR film is being irradiated by aliens!

(Sorry if I missed the reference - a comparison to tinfoil hats was the best I could think of...)

[vinny]

"What is the difference in materials and/or construction that matter for ir? "
One works, one doesn't.


Interesting to learn since I'm seriously considering getting a 45N-2. Couldn't you just throw an additional cloth over the bellows before you pull the slide?

Sure. Try it, see what happens.
Aluminum foil kinda works but I don't have the patience for that. Shiny bellows look great though.

[evan clarke]

Since I posted, I searched all the oldmthreads on this and quite a few have had success with a dark cloth around the bellows. I ordered a Harrison which is black on one side and reflective on the other. Need a different cloth for this 11x14 anyway.I can focus then throw the cloth in top of the bellows and give it a shot. I really want to use this film, I paid $95 for 50 sheets, it's fresh and just fine except for th IR fog..EC

[Kirk Gittings]

[QUOTE=vinny;875222]"What is the difference in materials and/or construction that matter for ir? "
One works, one doesn't.

Thanks for that useful tidbit.

Anyone else? I am curious. Is it just the sheer amount of material in the thickness of bellows or density or fabric vs. leather vs rubberized cloth?

[vinny]

haha! I don't know.
Leather works. The 45n-2 chamonix bellows are pretty thin but I don't know what makes it different than the shenhao bellows. I wish chamonix/hugo were willing to make some changes.
Evan, I'd try wasting a sheet of 4x5 taped to your holder rather than 11x14. You don't even need to go outside, just pull the slide for a few minutes on a sunny day. I tried the foil but it's not practical and I still got a bit of fogging even indoors.

[evan clarke]

My 11x14 is $1.95 a sheet and my 4x5 is $2.12!!

[evan clarke]

Over on APUG, Ole suggested going to the bdsm store and buying liquid latex..I wouldn't know where to find such a place.8>)..

[Kodachrome25]

What about a Mylar emergency blanket?

Back in my amateur astronomy days we used to use it as material for solar filters. I have a few of those blankets lying around. What I might do is sacrifice one for an experiment. I would fold it twice to create four layers and the tape it into an easy to use form that I can wrap the bellows at the infinity setting of my longest lens.

Designed for NASA Block IR material would work for sure, but I am not sure how pliable it is and the smallest it comes in is 4' x 25' foot rolls at $65.

[Brian C. Miller]

[QUOTE=vinny;875222]Anyone else? I am curious. Is it just the sheer amount of material in the thickness of bellows or density or fabric vs. leather vs rubberized cloth?

Some materials are simply rather transparent to IR. When I first started with Kodak HIE ever so long ago, I wasted at least 5 rolls due to my changing bag. I didn't have a darkroom, so I was loading my reels in a changing bag, in very indirect light. My small changing bag is made of black fabric outside, and black rubberized fabric on the inside. It stops normal daylight, but is pretty much IR transparent.

Harison tents are good, though. Not perfect, but in full sunlight the HIE only gets partially fogged.

My Graflex is fine for IR, and so is my Toyo. One has leather, the other has fabric.

[David R Munson]

I've been wondering if this is worth worrying about when doing long exposures stuff with Acros in a Chamonix 4x5. I have the 45n-1 and intend to do some long exposure work using a 10,000x ND and a 29 red filter. I've seen some examples of Acros used as an IR film, and wonder if I should be careful about this with my exposures being sometimes 40 minutes in midday sun. I wonder if enough IR might come through the bellows during that time to become a problem.

Once I have darkroom access again, I'll set up a test shot and post back here.

Two other things:

Are the 45n-2 bellows not IR-transmissive? If I replace my 45n-1 bellows with the current production bellows, would that fix the problem?
Do Shen Hao 4x5 bellows fit the Chamonix cameras? Hadn't heard of this before.

[Kodachrome25]

David, Hugo wrote me back today and confirmed the bellows on the 45N-2 are not IR safe.

I have been using 3, 6 and 10 stop ND filters in my black and white film work for years, even some last week. I am also curious about long time exposure in full sunlight with the Chamonix, I live and work at 8,000 feet and can often be well above 11,000 on a weekly basis, so this certainly concerns me.

Vinny tried the Shen Hao PTB bellows and said that he tried some Konica IR that it did fine but he got a little bit of fog if he had the dark slide out for a couple minutes.

[evan clarke]

Imjave bought a set of bellows frames for my Chamonix and have aluminized ripstop nylon and some commando cloth. I'm going to test a sheet of Aura in a sandwich of these cloths and if it's successful, will make a bag bellows foe my 11 x 14.... something I already need..Evan Clarke

[Kodachrome25]

So I made a 4 layer Mylar IR bellows coat today, did a two sheet test in which I set the camera out in blazing sunlight, sun to the left. I did one exposure after about 5 seconds from pulling the dark slide, one with exposure two full minutes after dark slide out, both came out perfect, no base fog.

Since this gizmo is essentially a bag bellows, no pleats, I have to make two of them, one at 6" ( 65mm-135mm ) and one at 10" ( 150mm-300mm ), the longest extension I could see using with IR. I made the small one first, will do the other tomorrow.

It looks funky, but it works...

[evan clarke]

Update..I have bought two sets of Chamonix bag bellows for my 8x10 and 11x14. I think they'll be IR safe and will test it in the next couple of days..

[Roger Cole]

Hugo participates, at least sometimes, here on the board. I wonder if we could persuade him to offer an IR safe bellows as an accessory or option?

[evan clarke]

I think these calfskin bag bellows are ir safe, will test in the next few days, subjects willing!,

[Roger Cole]

Well that's great when you want to use the bag bellows. What's the maximum extension with the bag?

EDIT: I see you are talking about 8x10 and 11x14 so that information won't really help me that much considering the purchase of a 4x5.

[evan clarke]

The good news is my bag bellows' are ir safe. On my 11x14' I can draw 600mm, so I'm thinking a 150-180 on the 4x5. Roger, you should contact Hugo, the company is very good at doing custom things at reglar price.

[Roger Cole]

Well I'm not going to bother him about it until I'm ready to buy a new camera. Hopefully later this year but it could be a lot later this year.

[vinny]

Roger,
Shen hao bag bellows also fit the chamonix 4x5, go to 210mm easily, and are ir safe. Standard chamonix 4x5 bellows are not. I'm also using standard shenhao bellows on my 45n-2 because they are suitable for shorter ir exposures (konica 750, kodak HSI). Some fog visible at a couple minutes. I've commented on a couple of these threads if you need more info.