X-ray and film

[straightshooter]

A while back we were talking about the effect of airport x-ray on film. As most of you know, I recently took an international trip and carried quite a bit of film with me. I was quite worried about the film since they kept my backpack camera bag in the x-ray for at least a minute (I could see it on the screen) and my film was only contained in a plastic bag inside the backpack. The types of film were Tri-X, Portra 160, Ultracolor 400 and Gold 200. Only the Tri-X I shot has not been developed yet so I can't comment on it but the Kodak Gold, Portra and Ultracolor my wife shot showed no visible effects from the x-ray exposure. But just to be on the safe side, I did pick up 3 old NIB lead film bags off eek-bay for future use.

CW

[woof]

Originally Posted by straightshooter

A while back we were talking about the effect of airport x-ray on film. As most of you know, I recently took an international trip and carried quite a bit of film with me. I was quite worried about the film since they kept my backpack camera bag in the x-ray for at least a minute (I could see it on the screen) and my film was only contained in a plastic bag inside the backpack. The types of film were Tri-X, Portra 160, Ultracolor 400 and Gold 200. Only the Tri-X I shot has not been developed yet so I can't comment on it but the Kodak Gold, Portra and Ultracolor my wife shot showed no visible effects from the x-ray exposure. But just to be on the safe side, I did pick up 3 old NIB lead film bags off eek-bay for future use.

CW

The general guideline seems to be that 800 ASA and above is at risk and you can request a hand inspection of that film.

I have several times asked airport personnel to hand inspect, and the first thing they asked was what speed it was. They would not do it and insisted on the x-ray machine when I told them it was all 400 and below. Don't be surprised if they make you empty the bags and still want to put it through the x-ray machine.

Chances are there will be no damage. I've been hit as many as three times on a single trip and it's always been fine. The following is not a bad summary:

Film and Airline Security - Taking Your Film on the Airplane

If you really want to "push" your rights, read this:

Avoid the X-rays

My experience with reading chapter and verse to officials however has, on balance, been less than satisfactory. Be prepared to have some other obscure chapters and verses read back to you whilst submitting to that strip search...

woof!

[ftpaddict]

While the general consensus (as woof and others have pointed out before) is that less sensitive films (< 800 ISO) are unlikely to be affected by Roentgen rays, I can't help but wonder why I have a warning on my AGFAPHOTO Vista ISO 200 film, warning me against passing the film through an x-ray machine.

[Nesster]

I've never had an issue with this. With Agfa, and perhaps others, this is corporate weasel speak: if the film is messed up we warned you, so don't go suing us.

[Ben_Edict]

Several years ago, Kodak had a big warning article on their website, which warned the photogs communitity to put ANY film through the then new X-ray scanner generation. After Sept. 11th, this article vanished. It is of no need anymore, as since that day I had not a single officer looking through my films by hand. Especially in the US, but also in the UK, HK, China and many other countries, I was simply asked: Do you want to get onboard that airplane or not? So I put my films through the machines and was lucky. For travelling, digital is godsent - at least in that respect. No damage to digital files by X-ray machines…

Otherwise the old rule was, that only 800 ASA and faster films are at risk.

Ben

[Wheatfield]

Originally Posted by ftpaddict

While the general consensus (as woof and others have pointed out before) is that less sensitive films (< 800 ISO) are unlikely to be affected by Roentgen rays, I can't help but wonder why I have a warning on my AGFAPHOTO Vista ISO 200 film, warning me against passing the film through an x-ray machine.

X-Ray damage is cumulative. Even slow speed films will be damaged if they get enough passes.

[jgredline]

Great topic and good timing. ''IF'' the film gets damaged, is likely to be damaged while new or after it has been shot?

[Wheatfield]

Originally Posted by jgredline

Great topic and good timing. ''IF'' the film gets damaged, is likely to be damaged while new or after it has been shot?

Film has what is called a threshold of exposure. This means that it can take a certain amount of exposure before it reacts.
It matters not if the exposure is light from a camera, or radiation from an X-Ray machine, or even just from getting hot in a car.
Once the exposure threshold has been reached, any additional exposure accumulates.
Now, X-Ray exposure is generally very minimal compared to what the film is exposed to in a camera, so film that has yet to be shot is less likely to show deleterious effects from being exposed to X-Rays than exposed film, which is already well and truly exposed past it's threshold.
Having said this, exposure is cumulative, so it is possible to X-Ray damage unexposed film if you give it several passes through X-Ray devices.
Unfortunately, in this modern age of paranoia, it is almost impossible to not have film X-Rayed when flying, and every time you step off one plane and onto another, your film gets dosed again.
Unexposed film is less easily damaged than exposed film, but all film is susceptible to X-Ray damage.
Unfortunately, photographers are an easy mark for security goons, so as a group, we can expect harassment from the nattering nabobs of paranoia that would have us live in fear of will'o'wisps, phantoms and shadows because it makes the masses easier to control.

[Ben_Edict]

Originally Posted by Wheatfield

X-Ray damage is cumulative. Even slow speed films will be damaged if they get enough passes.

This is in theory true. What I have never found is a spectral response curve for X-ray damage to films. That would be very interesting, as a simple intercontinental flight might cause more damage (exposition to high altitude radiation) than a simple X-ray scan. This is at least, what security people tell you at the airport to calm you down and to avoid any handsearching…

The point with any kind of radiation is: Some does expose the film, others don't. It is dependend on the energy of the radiation and the most energetic radiation might not be the one, that causes the damage. High energy radiation might just "go through" the film layer, without any interaction.

The question is, what energy (wavelength)) does a X-ray scanner use, what energy level do we have at high altitudes (that is the easiest to answer) and to which kind of wavelength does the film respond the most? Anybody got any info on that?

Ben

[ftpaddict]

Originally Posted by Ben_Edict

The question is, what energy (wavelength)) does a X-ray scanner use, what energy level do we have at high altitudes (that is the easiest to answer) and to which kind of wavelength does the film respond the most? Anybody got any info on that?

Ben

Wikipedia kindly points this out:

Originally Posted by someone on Wikipedia

An X-ray (or Röntgen ray) is a form of electromagnetic radiation with a wavelength in the range of 10 to 0.01 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (30×1015Hz to 30×1018Hz) and energies in the range 120 eV to 120 keV

So somewhere between these values, I presume.

[Ben_Edict]

Originally Posted by ftpaddict

Wikipedia kindly points this out:

So somewhere between these values, I presume.

That is a factor of 1000x - and does not much to answer my question. We can easily find values for high altitude radiation (which is very mixed, too) and for the definition of X-rays. But at what exact frequencies do the X-ray scanners work. You won't find any info on the market leader's Smiths Heimann website, for example.

And how is the film's response to these different wavelengthes?

If we know the scanner's energy levels (modern scanners employ multi-energy X-ray sources) and the film response, we could deduce, how much a certain film is affected, how often it could be X-rayed, before the damage is visible etc.

Ben

[Mike Cash]

The only x-ray device my film ever goes near is the honking massive one that Customs uses to shoot through two layers of Corten steel and about 2 1/2 meters of whatever happens to be in between them. It is, quite literally, "big enough to drive a truck through".

I'm real diligent about taking all film out of my truck when it goes through the x-ray chamber.

[VF-19]

A year ago I went to Vancouver (from Ottawa) to visit a friend, and I took along all of my camer equipment I had at that time (Spotmatic II, K1000, flash, and a bunch of lenses). It was heavy (everything was metal), but to insure that I wouldn't be wasting my film (I took ISO 200 along for the ride), I only took one roll along with me to Vancouver.

I wound up with some neat pictures from 39000 feet, and the film survived just fine.

On the leg back from Vancouver, I had several rolls of ISO 200 film, and they survived just fine. But I had some small complications... I keep my Nintendo DS in a metal case, and for some reason the X-ray machine didn't penetrate it (but it did give me wonderful pictures of the innards of my lenses), and I was asked what it was. The officer was quite amused.

The security personel told me that the X-ray machines were safe up to ISO 1600. But honestly, I'm not even going to tempt fate.