X-Rays, Remjets and X-amples of What Can Go Wrong With Film
About every week at the lab, a customer would drop a roll off and express their reservations on the fact that their roll had been through an X-ray security check at the airport, and that their roll was, in their words ‘probably fucked’. And yes, when I was new to the lab work, I would express my sympathy, and cite the conventional wisdom- the 5th commandment of the film shooter “THOU SHALL NOT TAKE FILM THROUGH THE X-RAY SCANNER.”
The mystery of X-ray gave birth to an incredible variety of superstition and practice. There were many who would insist of having their film cache hand searched. Some brought their rolls wrapped in tin foil, as if the government was listening in. One person with more forethought had bought specialised lead line carrier to protect their film.
Any time any one told me that they thought their film was damaged by X-ray from multiple international flights I would take a look at their contact sheets and check for signs of damage. After a while I lost count of all the rolls that customers had assumed were fried by X-rays but turned out totally fine.
I started looking online to see what the actual effect of X-ray damage is and found a very old Kodak reference from 2003:
X-ray damage in 2003 was a big deal- everything was shot on film. The whole article is a horror show for anyone who has shot anything remotely important on their film and traveled by plane- basically once you have taken it through the scanner, it's cooked- there’s nothing you can do to correct the damage.
And the damage is severe- as you can see on this 800 film example that even a single scan looks positively catastrophic:
But even 400 film, at least according to this Kodak test, will get completely fried if you take it through:
From most of the articles I have read about X-rays and film the advice and the examples given are taken as gospel. I had never read an articles disputing this example, and yet I have never seen anything like these examples in my time at the lab.
From further online research I couldn't find many recent accounts of X-ray damage either, other than a few dubious claims that X-rays have damaged film. From what I can see, it’s most likely light leaks from their camera, or bad digitization or heat damage. X-ray damage across the negatives should be visible, like in the Kodak article or this example on Flikr:
One example that I found that definitely was X-ray damage was this roll of Cinestill 800T:
Here I can see some of that wavy line effect visible on the edges of the film. The Kodak website notes that cinema film is particularly sensitive to x-rays and this could be the reason the roll has been damaged (although still a far way off the complete destruction apparent from the Kodak scans).
As an aside on cinema film; with Cinestill 50D I am familiar with problems relating to the removal of the remjet layer. A few rolls I have scanned had part of the remjet still attached to the film, which created strange water mark looking damage, and uneven development. Example here of a shot I scanned for a customer who has generously gave me permission to demonstrate it:
I had previously encountered this in a roll I had scanned for @troyplease, so this confirmed by suspicions about the problems with remjet removal:
The photographer of the first picture believed the roll had been water damaged. I have seen many rolls destroyed by water (particularly defective water proof cameras) and this definitely was not the case. Low impact water damage tends to cause uneven colour shifts and bad water damage just strips all the gelatin off- leaving completely clear film. The point of this digression, bringing it back to the topic is this- what you assume is one problem in your handling, may actually be an issue with the process or production of the film itself if you cannot see visible evidence of X-ray damage.
All of this got me thinking- what would really happen with if I intentionally exposed my own high ISO film to the X-ray machine? I had a holiday planned in Asia, so I loaded up on a variety of different film types, varying from 100 ISO to 1600, to see what would happen to my photos after blasting them with X-radiation?
At the security gates at Kingsford Smith Airport, I threw all of the film in my luggage and had it go through its first scan. I have to admit I winced at the idea of shooting all this film and having it come back completely useless and fogged.
Then another security scan after I left Shanghai airport to get on the Mag-Lev train. The Chinese government doesn’t cock around when it comes to security, as I would soon realise: Every time I got on the subway for a week (at least 2 times a day), I would have to go through an X-ray scanner, and so too would all my film in my bag. I lost count of how many times it got X-rayed.
And to the results! Here they are for comparison, but as you can see, there is no damage apparent from X-ray scanners like was saw in the Kodak example:
When I asked an airport security officer, they told me that most airports since 9-11 have regularly updated their X-ray scanning technology, which made them not only more effective but also less likely to damage film, however it is difficult to cite this claim. I common piece of advice I have found on forums was taking caution when flying into airports with older scanners, particularly remote places in Asia or Sub Saharan Africa.
However the only visibly X-ray damaged film I have ever scanned came through Los Angeles LAX:
From the same roll, seemingly unscathed:
A few frames are damaged, but from what I can see, the frames that don’t have any wavy radiation lines on them look totally normal. It seems to effect underexposed areas far more noticeably than exposed ones. Thank you to ‘Christo’ who have me permission to share these:
What I can say with a high level of confidence is that your film is going to be fine if it’s not in your checked luggage and not scanned by a CAT scanner.
According to this article, by How Stuff Works:
“A common misconception is that the X-ray machine used to check carry-on items will damage film and electronic media. In actuality, all modern carry-on X-ray systems are considered film-safe. This means that the amount of X-ray radiation is not high enough to damage photographic film. Since electronic media can withstand much more radiation than film can, it is also safe from damage. However, the CT scanner and many of the high-energy X-ray systems used to examine checked baggage can damage film (electronic media is still safe), so you should always carry film with you on the plane.”
Ok fair enough, so I may not have had my film damaged by my carry on scans, or in the subway- but also I had the film in my luggage on 4 separate flights, with still no noticeable damage to the film. Maybe even most CT scanners have been upgraded so as not to damage film? Or much more likely, that not damaging film has occurred in incidence with improved security scanning technology.
Many times people mistake X-ray damage for bad scans, or heat affected film;
The Dark Room has a great comparaison of film damaged by heat:
This Digital Rev post claims that her film was badly damaged after being scanned 11 times. Mostly it just looks like a film that’s been heat affected- there are no calling card waves on underexposed parts of the film. There are some bars of uneven exposure, but I’m not ready to call this as X ray damage, without being able to look at the negatives.
I hope to and plan to follow up with accurate comparison of an radiations effect on film. Particularly if you have expertise in X-rays, CT scanners and airport security procedure, please let me know, because I would first of all love to share your insights, and also, I really want access to a X-ray scanner to it to the test!
But from the information I have gathered to date, I can conclude that X ray damage happens a whole lot less than people suppose it does, and encourage you to cast a more discerning eye on your negs that you may have thought were damaged by airport security.