Beach Bum k10
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This is common knowledge, I'm sorry you don't know about this. Now you know, and it's freebie, you don't need to pay me for the information. And you are welcome.
Film and XRays
- Thread starter nusspli
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This is common knowledge, I'm sorry you don't know about this. Now you know, and it's freebie, you don't need to pay me for the information. And you are welcome.
blacknet
Contributor
Hello,
I'm calling BS on this one. X-ray of high speed film WILL be damaged! TSA regulations, section (49CFR1544.211(e)(4) states no high speed film is to be x-rayed. If you request a hand check they *MUST* hand check it. I have held up security screening lines with this and they caved in. If you cave in you are doing a dishonor to all photographers worldwide.
Ed
Of course, but how many people shoot 3200 B&W? I happen to carry a couple of rolls with me and show these to the screeners. It works sometimes. Other times they insist I take those rolls out for hand inspection while x-raying the remainder. I also carry a copy of the FAA regulations with me, but I've had a screener in Maui tell me that she doesn't work for the FAA (remember, these are generally people who aren't smart enough to work at McDonalds).
I win probably 95% of my "battles" with screeners, but that's not the point of my posting. My point is that it's not worth worrying about the other 5%. I tested the effects of airport x-ray machines on real film in a real world situation. After 14 trips through the machine, even the 400 speed film showed no evidence of exposure. BTW, this wasn't my evaluation of the film. I use Chrome Digital in San Diego as my E-6 lab, and they offered to develop and evaluate the film for free if I let them keep the film for reference. They measured the film on a desitometer and found no difference between this film and fresh, unexposed film, along with no evidence of streaking or other evidence that the x-ray exposure had altered the film.
Alan
My dive buddy is a physicist and ALWAYS has his film hand-checked. We just returned from Nikon School yesterday and on our way down my buddy explained it to me like this....
Each trip through x-ray is basically the equivalent of one f-stop. On the way to Cayman we were x-rayed 4 times? Are you willing to chance 4 f-stops of variation to your film?
Our instructor for Nikon School, Frank Fennell, echoed the same warnings as my buddy.
Why take the chance....insist on hand checking...it's your right.
One caveat tho....the new x-ray machines that x-ray your CHECKED baggage will fog film for sure. They have signage up warning this as well as overhead pages every several minutes....plus the sercurity person taking the baggage and placing it on the conveyor was warning passengers as well.
Each trip through x-ray is basically the equivalent of one f-stop. On the way to Cayman we were x-rayed 4 times? Are you willing to chance 4 f-stops of variation to your film?
Our instructor for Nikon School, Frank Fennell, echoed the same warnings as my buddy.
Why take the chance....insist on hand checking...it's your right.
One caveat tho....the new x-ray machines that x-ray your CHECKED baggage will fog film for sure. They have signage up warning this as well as overhead pages every several minutes....plus the sercurity person taking the baggage and placing it on the conveyor was warning passengers as well.
OP
nusspli
Contributor
"the new x-ray machines that x-ray your CHECKED baggage will fog film for sure. They have signage up warning this as well as overhead pages every several minutes....plus the sercurity person taking the baggage and placing it on the conveyor was warning passengers as well"
That's what I had heard also. So, basically the take home message is bring the film in a carry on bag and ask to get it hand inspected- if they refuse, then it probably wont matter too much.
That's what I had heard also. So, basically the take home message is bring the film in a carry on bag and ask to get it hand inspected- if they refuse, then it probably wont matter too much.
That is absolutely, positively untrue. If that were the case, the film I sent through the x-ray machine 14 times would have been totally destroyed. If one trip through the x-ray is equivalent to 1 f-stop, everyone in the world would have noticed the effects and would be screaming for hand inspection.
Dee, I realize that one should be nice. But isn't posting complete and utter BS just as damaging??
sheck33
Contributor
agstreet is right, each increase of F-stop halves the amount of light captured by the lens, so each decrease doubles the amount of light captured. So if one uses 'f-stops' to compare different exposures than 1 f-stop change, while maintaining the same exposure TIME, would make a HUGE difference and would not go unnoticed. But an f-stop really is not a measure of 'exposure', the 'f-stop' tells you something about the aperture used. (which of course influences the exposure)
If everyone took everything that is said on these message boards as absolute gospel, then yes...posting BS would be damaging. But since, hopefully, everyone realizes that what is said on these forum is what someone else thinks or knows to be true and/or is their opinions. It's information to take into consideration when making their own decisions.
You've explained the process you took to disprove the X-ray damage and why you think the results are truthful. That's all you can do. To state "That is absolutely, positively untrue." is your opinion, and could be considered BS by others. It's up to others to believe your method delivered accurate results or not and nothing you claim is going to change that. You can't make them believe you. Just as no one is going to change your mind that there IS damage done. The other 'side' has just as strong a case that there IS damage done to film when x-rayed as carry-on. But in these forums, the verbal exchanges with be made with respect to the 'other side' and in a civil manner, on both sides.
So it's a draw. Everyone needs to take the information as presented and make your own decisions.
blacknet
Contributor
Hello,
If you kindly read the material that you requested, that I provided for you, you will see that TSA regulations states to NOT scan anything over 100 speed film.
So in your test you have FB+F results form airport xray machines? Please post them as I would love to see the results. If they found no difference then several things comes to mind: the user failed to accurately use the denso, the wrong type of denso was used, or the user just didn't have a clue what they was doing. Should have taken that film to someone who does zone work, bet their equipment would have picked it up. Most 'color labs' have the wrong type of equipment to perform this type of test.
Ed
Well, I read the thread you posted, and I'm not seeing the same things you are. First, the information from the TSA web site:
http://www.tsa.gov/public/display?theme=56
states that cabin baggage x-ray will not hurt anything under asa 800.
I'm not sure what you mean by FB+F, nor how you suggest I post black strips of film to a web board. If you mean densitomer readings, I don't have those. I simply took the word of a highly respected lab that there was no difference between my three test rolls and fresh, unexposed film.
One error I did find on the previous thread was a misunderstanding between total dose and voltage. This is in reference to using lead lined bags. While the total radiation dose does not change with sample density, the tube voltage does. Voltage affects the "penatrating" power of the x-ray, while dose is the total amount of radiation the sample is exposed to. A very loose analogy would be voltage and charge. The two have some relationship to each other, but are independant quantities.
As for TSA regulations, you're correct that hand inspection is required if requested. The problem is that not all screeners know this (gotta love that great TSA training) and some have been known to cop a major attitude when you challenge their perceived authority by asking for hand inspection. I've been successful with escalating the issue to a supervisor a couple of times, but I specifically remember an incident at LAX (Bradley terminal) where I was told in no uncertain terms that I was not getting through the checkpoint without my film being x-rayed. Armed guards were starting to get antsy, and I didn't feel like winning a philosophical battle at the expense of spending some time in a cell.
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