There is an old piece of wisdom among film photographers: anything ISO 800 or slower can safely go through the carry-on scanner. It dates from a time when every airport checkpoint used conventional X-ray machines. But as CT scanners have arrived at one airport after another, film manufacturers have started changing what they tell customers. Before you think about film speed, there are now two things to check. What kind of machine is at the checkpoint you will walk through, and is the film in your bag still undeveloped?
CT is X-ray too
In the words of the U.S. Transportation Security Administration (TSA), a carry-on CT scanner uses X-rays to build a three-dimensional image of what is inside a bag. Screeners turn that image this way and that on the screen as they look it over. Older scanners showed only a flat image. People tend to talk about X-ray scanners and CT as if they were different machines, but both use X-rays. For convenience, this article calls the older flat-image scanners "conventional X-ray" and the newer 3D scanners "CT."
What the manufacturers say
HARMAN, the maker of ILFORD film, says in its technical FAQ that it considers the new carry-on CT scanners unlikely to be safe for its ILFORD and KENTMERE films, whatever their speed. It cites initial test results and adds that it will revise the guidance after further testing. Conventional X-ray machines get separate treatment, and even there HARMAN advises asking for a hand inspection for DELTA 3200. It also notes that whether you get a hand inspection varies by airport and by country.
Kodak, in shipping guidance for its motion picture film customers (updated June 2023), warns that the new carry-on CT scanners will fog undeveloped film. In Kodak's view it makes no difference whether the film is fresh or already shot. If it has not been developed, the risk is the same. Both companies say to keep undeveloped film out of checked baggage, because checked bags are screened more intensely than carry-ons.
The two sets of guidance cover different ground, though. Kodak's document was written for motion picture film, and HARMAN's assessment applies only to its own products. Neither offers figures on how much damage occurs or after how many passes it becomes visible. Nor could we find anything saying ISO 100 or 400 film is fine to put through CT.
Kodak's film storage guidance also explains that X-ray effects add up. Each pass through security, at departure, on a connection and on the way home, can add a little more fog and grain. That passage, however, was written with older low-dose carry-on scanners in mind, so it is hard to apply directly to the new CT machines.
This figure accompanies Kodak's shipping guidance. It names the equipment and nothing more, with no model, dose, number of passes or test date. Presenting it as what a single trip through a modern carry-on CT scanner does would be reading too much into it.
Developed or not?
Film you have not shot yet needs to stay away from CT and strong X-rays. It makes no difference whether it is still sealed in the box, sitting in its canister or loaded in a camera.
The same goes for a roll you have shot to the last frame and rewound. Until it is developed, it still reacts to light and X-rays.
Developed negatives and slides are another matter. Kodak explains that processed film no longer reacts to light, and suggests having film developed at your destination before you fly as an alternative. Heat, humidity and scratches, of course, are a separate problem.
For finished prints, we found nothing in the official documents we reviewed that connects them to airport CT. Unprocessed photo paper and instant film are different materials from finished prints, so check the guidance for each product separately.
A hand inspection is only a request
The TSA advises carrying undeveloped film, and cameras with film in them, in your carry-on, or asking for a hand inspection at the checkpoint. The item table on the same page lists film as allowed in both carry-on and checked bags. But being allowed to bring film along is one thing, and the film coming through unharmed is another. The page also states that the officer at the checkpoint makes the final call on what is allowed.
Kodak, too, notes that local staff can turn down a request for a hand inspection. And a U.S. agency's recommendation does not carry over to airports in other countries. London Heathrow says security equipment and rules differ from airport to airport, and tells travelers departing from elsewhere to check that airport's guidance. The Heathrow FAQ we checked says nothing about guaranteeing a hand inspection for film either.
One hand inspection at a Korean airport
So what about Incheon and Gimpo? We found nothing on hand inspection of film in Incheon International Airport's FAQ on restricted items or in Gimpo International Airport's security screening guide. For now, travelers' own accounts are filling the space the official guidance leaves empty. One film user posted a detailed write-up online of how they applied for a hand inspection in December 2025. The writer says they worked out their own method by drawing on posts in the DCInside film camera gallery and on Naver blogs. What follows is our brief summary.
According to the writer, the line at Korean airports is ISO 400. Film rated ISO 400 or higher will be hand inspected on request, but slower film can be hand inspected only with an official special security screening permit letter. The writer describes this as the airport manual, but it is not a standard we have confirmed in any official notice.
Here is the process the writer lays out. First, download the Application for Permission for Special Security Screening of Items (특별 보안검색 물품 허가 신청서, Attached Form No. 1) from the website of the Ministry of Land, Infrastructure and Transport (MOLIT) and fill it in. The form lists a processing period of three days. On the application, list only film below ISO 400, down to the name, format, speed and quantity. The writer's advice is to leave out anything rated ISO 400 or above. Submit it through Munseo24, the government's e-document service, to the security division of the Regional Office of Aviation that covers your departure airport. Incheon and Gimpo fall under the Seoul Regional Office of Aviation. Attach supporting material such as Kodak's advisories as PDFs, and when the reply letter arrives, print it out. At the airport, hand the screener your film, sorted by type into separate zip bags, together with the letter.
The writer's letter cites Article 13(3), subparagraphs 4-2 and 5, of the Enforcement Decree of the Aviation Security Act as its basis. The sample application the writer shared was for a domestic flight from Gimpo to Jeju. The writer also reports on the equipment they saw for themselves. As of December 2025, they say, most checkpoints at Incheon's Terminals 1 and 2 had switched to CT, while Gimpo and Jeju still used older X-ray machines.
We have not yet checked the MOLIT form page the writer linked, or the text of the Enforcement Decree of the Aviation Security Act, for ourselves. The form name, the article numbers, the ISO 400 line and the equipment at each terminal all come from the writer's account. Keep in mind, too, that even with a letter in hand, the final decision rests with the staff on site. And the fact that ISO 400 and faster film can reportedly be hand inspected just by asking does not mean it is safe to put through CT. As we saw above, Kodak and HARMAN set no ISO threshold for CT.
Before you go
These are our suggestions. None of them will get you a hand inspection at every airport.
- Look up the official guidance in advance for every airport on your trip, at departure, transfer and return. Even an answer you get ahead of time is no guarantee it will hold at the checkpoint.
- If you are flying from a Korean airport with film below ISO 400, look into the permit application described above well in advance. Leave plenty of time for the processing period printed on the form.
- Pack film, and cameras with film in them, where you can get them out quickly. Kodak recommends a clear, resealable bag.
- Before anything goes on the belt, tell the screener it is undeveloped film and ask whether a hand inspection is possible. If the answer is no, follow the staff's instructions.
- Do not put undeveloped film in checked baggage.
- If a hand inspection is hard to count on for your trip, you can also buy film where you are going and have it developed there before you fly home. This is an alternative Kodak suggests.
Some readers may be thinking of a lead-lined pouch. Lomography's Korean-language guide carries a link to buy one alongside a description of how it protects film. But we found no independent test of how much it actually blocks in front of a CT scanner, so we do not recommend it as a substitute for a hand inspection.
Film speed is still a number worth weighing. But there are questions to ask before it. What machine is this checkpoint using, and is this roll still undeveloped?
