Airport X-Ray Machines Causing Blemishes on Film? (1 Viewer)

[Jay Taylor]

John & Tom,

Thanks for helping me find the cause of the blemishes. The example photo was taken on top of 10,023 ft. Haleakala Crater, in Maui. Since we were above some of the clouds it appears to be taken from an airplane but wasn’t.

I blotted out the subjects that were in focus to comply with Internet Posting Rule #79: “Never post a picture on the Internet of you and your wife wearing Hawaiian shirts.”

The photos were taken with a Fuji Discovery 975 Zoom 35mm camera. As you suggested I checked the negatives and the blemishes did show up when I made a 1600dpi scan.

For now I’ll blame the blemishes on a dirty camera lens even though shots taken later did not show the blemishes and I didn’t find any visible contamination on the lens.

Fortunately Photo Shop can clean up the blemishes.

Thanks guys,

Jay Taylor

 

[Jim_C]

Slightly OT:

Are the X-Ray machines an issue with camcorder tape (digital8/Hi8)?

 

[Aaron Reynolds]

This could also be staining from the processing -- either inconsistent bleaching or hard water staining.

Ask your lab if they can run the affected strips through the film processor (not the printer) again. This will absolutely cause no harm to your film unless their machine is dirty and scratching negatives. C-41 is a pretty bomb-proof process, which is why fixes like this are possible.

I explained that since the film had already been x-rayed I was concerned that repeated exposure would damage the film.

She said it wouldn't effect the film

Wrong. If the machine is only safe up to ISO 1000, because photographic exposure is cumulative, two passes will then only be safe to ISO 500, four passes to ISO 250, and so on.

When travelling to North Carolina last Christmas, we had to go through LaGuardia in New York. While at Toronto they were very relaxed about it and were happy to hand inspect my film, at LaGuardia it took a bit of work. However, as soon as they said that they were concerned because the film was sealed in boxes and foil wrappers, I offered to open and unseal all of them, since I was going to shoot the film anyways. This made them very happy, though they preferred to open them by themselves after I showed them the quick way to pop the box and peel the foil. They swabbed each and every roll, which took a bit of time, but I was prepared for that.

Be firm, but when the opportunity to offer a compromise like that comes up, jump at it. After all, they are just doing their job as best they can with the limited information they have been given.

Last summer, my wife and I went to Prague, and I took a lot of high speed negative film with me. Unfortunately, we had to pass through Heathrow both ways and I knew that under no circumstances would they hand-check film there. I knew that my 800 ISO neg would be okay through a single pass, but I had grave misgivings about multiple passes. But I had thought about this before the trip, and that was why I was packing negative film in the first place instead of transparencies -- C-41 is a pretty bomb-proof process, so I did some research and found some good labs, and had all of my negatives processed (without prints) before returning, and everything was fine.

Another option, for those worried about it, is to scope out photographic shops before making your trip -- if the prices are comparable for your favourite films, why not buy them at your destination? The prices at the bigger places in Prague were actually very competitive, especially with quantity purchases.

If anyone is going to Prague, PM or e-mail me and I'll tell you where to find the good labs. I had a lot of help from the Czech members of the Pentax Discuss Mailing List, who are especially nice guys, and who mostly agree on which labs are good and which are bad.

 

[Scott Strang]

Are the X-Ray machines an issue with camcorder tape (digital8/Hi8)?

I've heard that generaly it's the magnets in the x-ray machines and not the "x-ray" that causes a problem.

 

[JohnRice]

Jay, Aaron does bring up a possible cause. Unfortunately, I expect the film has been cut so it wouldn't really be feasible to run it through the processor again. You now know the dirt was not in the printing, which is unfortunate. If it was some residue left from poor processing you can probably see some other indication of that by looking at the negatives, if you want to take the time.

I can go into how to check it if you want. If that is the case, you might be able to take it to a custom lab or someone who processes their own film to have it re-washed, which could fix it. It's a lot of trouble. Just depends on what hassle you want to go to.

 

[JohnRice]

Oh yeah, Jim. Like Scott said, I doubt the X-rays themselves will harm video tape recordings, but there is probably an abundance of electro magnetic radiation inside that scanner, which definitely would have a negative effect. However, it may really only be bad for tapes that have already been recorded and not really on blank ones. In other words, I don't think it would physically harm the tapes themselves, but would have an effect on the recordings.

 

[Jay Taylor]

John,

Visibly I can't see stains or blemishes on the negatives.

It took scanning the negatives at 1600 dpi to reveal the blemishes.

You're right that the film has already been cut into strips.

Also concerning fogging from x-rays:

Is it possible for reflections of the x-ray beam off of metallic objects to cause irregular fogging similar to the blemishes on my photos?

Jay Taylor

 

[Jim_C]

Thanks for the replies.

I'll have to think about what to do with the tapes. We're taking my 3 yr old son to Disney for the first time and I want the tapes to survive the trip back.

We're bringing film as well but I've been dealing with that for awhile now so I don't have too many concerns. I've not had a problem with hand checking in the past. Hopefully it won't be a problem on this trip.

 

[JohnRice]

Jay, I can think of absolutely no way an X-ray would cause the blemishes you got. X-rays will cause additional exposure, which will make areas on the prints that are lighter and usually colored. The only ways I can think of creating what you got is by obstructions (like big clumps of dust) in the light path to the film when it is exposed or something that reduced the density of small parts of the negative in processing. I have processed C-41 (which is the process for color negatives) but I don't exactly know it inside out. Still, my gut feeling is that any residue from that would not only make lighter spots on the print but would also probably have some sort of color tint to it as well as some color fringing. I don't see any of that in the shot you posted. The main cause of minus density on prints is air bubbles on the film in the developer, which is virtually impossible in commercial processors, unless something is seriously wrong, but those are not air bubbles as far as I can tell. The more I think about it, the more convinced I am that it was most likely caused when the film was exposed.

There is a slim chance it is a defect in the film, but I honestly think the chance of that is astronomically small, unless you ended up getting "Kodak" film that was actually some incredibly bad film packaged as Kodak. Not very likely.

If I could physically see the negs, I might be able to tell better. You might take them to the lab and see if anyone can give you an idea what caused it. Unfortunately, they will most likely give you whatever is the first cause they can think of that doesn't involve them.


EDIT: It probably needs looking at the negs under magnification to see what could be the cause. If it was after exposure and during processing or something, there will tend to be some sort of "relief" around the blemishes on the emulsion side. If it was in the exposure, there generally won't.



Jim, I would either handle the tapes with the film or ship the tapes back by themselves.