
Kodak Alaris warns the TSA's new airport CT scanners can damage undeveloped film - lelf
https://www.dpreview.com/news/4631062971/kodak-alaris-warns-the-tsa-s-new-airport-ct-scanners-can-damage-undeveloped-film
======
joecool1029
My first job over a decade ago was managing a photo lab. The x-ray machines
would often damage film that people traveled with. Amateur photographers just
weren't aware. The damage typically looks like white fuzzy diagonal lines
across the image. It's not enough to completely destroy a picture, but it'll
ruin it. The most common widespread damage we saw were people that bought like
50 disposable cameras for their Caribbean wedding, then brought them back home
to get developed.

The worst overall damage we had at that lab was when high school kids would
run customer Tri-X film through the C-41 lab. That would completely wipe the
film, no recovery whatsoever possible.

~~~
Finnucane
Ever put the fixer in first? That's fun too.

~~~
cannam
There are companies like Silbersalz
([https://silbersalz35.com/](https://silbersalz35.com/)) selling ECN-2
cinefilm stock in 35mm cartridges. You have to return the film to them for
processing, rather than take it to a C-41 lab - and they warn that if you send
them to a C-41 lab, you can damage the lab's equipment and ruin everyone
else's photos as well as your own.

I don't know how paranoid the warning is, but that seems like it could be
pretty bad.

~~~
joecool1029
> There are companies like Silbersalz
> ([https://silbersalz35.com/](https://silbersalz35.com/)) selling ECN-2
> cinefilm stock in 35mm cartridges.

To be fair, anyone buying that likely knows what they're getting into. Tri-X
was sold next to C-41 film in every store, so a lot of people would just grab
it when they wanted B&W thinking it was the same thing to develop as color
film. (Yes, there is B&W C-41 film as well)

~~~
cannam
> To be fair, anyone buying that likely knows what they're getting into.

True, I'm just dwelling on the possible consequences. I have some Silbersalz
film myself that I haven't used yet, and I'm actively imagining everything
that could go wrong.

> Yes, there is B&W C-41 film as well

Ilford XP2 - it looks a bit different from typical B&W film, with very flat
whites.

I used to love XP1, which came out sepia when processed C-41.

------
ohazi
How much radiation would it take to flip a bit on an SSD? What about RAM (many
people send their laptops through in a suspended-to-RAM state)?

I would assume that RAM is more susceptible, since we still store a single bit
per RAM cell, while some SSDs now store multiple bits per cell, but I've never
tried to do the math on "what would it take to actually make these problems
start to appear?" Might be a fun exercise... has anyone looked into this?

~~~
cm2187
Don't SSD have some kind of cyclic redundancy check?

~~~
Seenso
> Don't SSD have some kind of cyclic redundancy check?

Yes, but they're pushing the the technology so far to get higher densities
that error correction is required for _normal operation_ :

[https://en.wikipedia.org/wiki/Multi-
level_cell](https://en.wikipedia.org/wiki/Multi-level_cell)

> The primary benefit of MLC flash memory is its lower cost per unit of
> storage due to the higher data density, and memory-reading software can
> compensate for a larger bit error rate.[5] The higher error rate
> necessitates an error correcting code (ECC) that can correct multiple bit
> errors; for example, the SandForce SF-2500 Flash Controller can correct up
> to 55 bits per 512-byte sector with an unrecoverable read error rate of less
> than one sector per 1017 bits read.

Making the cells smaller and cramming more bits per cell reduces the amount of
energy/radiation required to trigger a bit flip, making the data more
vulnerable. It sounds like they may also be increasing the energy put out by
the scanners. Not a very good combination if you care about your data. Maybe
they'll push the fraction of storage reserved for error-correction data even
higher to compensate.

IIRC, radiation-hard chips often used processes with larger feature sizes and
different materials in order to be more resistant to the effects of radiation.

~~~
jrowley
Interesting! I had no idea there is increased need for error correction.

Regarding radiation, I just found this cool link about ICs in space:
[http://cpushack.com/space-craft-cpu.html](http://cpushack.com/space-craft-
cpu.html)

From my understanding they often use redundant CPUs computing the same
instructions in lockstep and rollback when they disagree.

------
modo_
I've never run into any trouble getting film hand checked while traveling
within the US.

Sadly it's a completely different story internationally. Indian security has
been the strictest in my experience -- flat out refusal to do anything other
than run the film through the X-Ray machine. I don't travel with fast film
(800+ ISO) anymore. It's just not worth the stress.

~~~
klodolph
I decided to switch to digital for anything where I want to go over 400 ISO.
My personal feelings are that the image quality of 800 ISO film is just
terrible. YMMV based on personal preference, I know people who really like the
look of fast film.

~~~
ghaff
Leaving aside the work associated with chemical processing generally, you
could “coax” ISO/ASA 400 B&W films up to 1600. Maybe 2400. But you definitely
lost a lot as soon as you started pushing.

For a lot of photography, especially basic journalist event stuff, I find the
fact that I can go to about 3200 without even thinking about it a huge benefit
of digital.

~~~
klodolph
Sure, you can push two stops if you like swaths of flat black in your photo.
Same thing with TMZ, which says “3200” on the box but if you look carefully it
doesn’t actually say “ISO 3200”, because its ISO speed is actually something
like 800.

------
hadtodoit
Flying out of SFO, the security gave me a heads up about putting aside film.
They are not TSA, but at least they had been briefed.

~~~
tpmx
That's really impressive, given how few people are using film.

~~~
tecleandor
Seems like there are relatively more film users at SFO (insert outdated
hipster joke)

Jokes aside, I'll take care from now on, film goes at least two two four times
through the scanner on a plane trip...

------
kailuowang
I have been traveling with a Filmguard bag. Sometimes they take it out and ask
for a hand inspection, sometimes they don't they rarely insist on scanning the
films themselves outside the bag. Regardless never check-in your films.
Nothing can protect them from the powerful scan for check-in luggages.

~~~
supernova87a
Those bags do not do what you think they do.

When a TSA x-ray operator sees an opaque bag on the screen, he/she just turns
up the exposure until the contents are visible. Not much help there for your
film.

~~~
neetdeth
Turning up the exposure on the screen does not do what you think it does.

With a line-scan X-ray, the bag is well out of the beam path by the time the
operator sees the image. But it's probably coming in through a 12 or 16-bit
ADC, so there's a lot more range than can be effectively displayed on screen
(at least with a simple linear+gamma mapping). It's a matter of adjusting the
display mapping to see inside denser objects.

The X-ray source power needs to be high enough to deal with the worst case
scenario of large/dense luggage. If you can give your film a 10x lower dose
while still allowing enough X-rays through that the operator can clear it,
that sounds like a good idea.

It just has to be traded off against the fact that deliberate shielding is
likely to be frowned upon, and they may take the film out and run it through
"naked" anyway. Seems worth a try, but I'd definitely use a commercial product
marked for the purpose and resist the temptation to DIY it.

------
anfractuosity
On the topic of film, this little short video "Behind the Film - Inside the
ILFORD factory" is cool -

[https://www.youtube.com/watch?v=JXpoALotxf0](https://www.youtube.com/watch?v=JXpoALotxf0)

They also have a lab that do b&w prints from digital files on photo paper
interestingly.

~~~
madflo
ILFORD is still selling photo paper in rolls with the specific chemicals
required for regeneration of baths. It does allow a skilled lab operator to
use Durst Lambdas or even a 1hour laser-based minilab like a Noritsu QSS or
Fuji Frontier to print on real b&w paper!

However, the same skilled operator should be able to calibrate her minilab in
order to obtain decent looking b&w prints on color-based paper (RA4 process -
used by Noritsu & Fuji).

~~~
joecool1029
>However, the same skilled operator should be able to calibrate her minilab in
order to obtain decent looking b&w prints on color-based paper (RA4 process -
used by Noritsu & Fuji).

It's actually a fairly good way to test if your lab sucks ass. B/W is not
forgiving to poorly calibrated equipment or chain stores that are cheaping out
on replenishment.

small nitpick: RA-4 is a Kodak process. The Noritsu minilab I ran used Kodak
chemicals. Fujitsu labs typically use a 'compatible' version of their own that
can't be called RA-4. While the two systems work, we always found C-41
Fujifilm looked inferior printed on the Kodak processes and vice-versa.

------
colejohnson66
Genuine question: Why do people still use film anymore? I know some big movie
studios do sometimes use it (The Hobbit comes to mind), but I don’t understand
why anyone would use film when we have DSLRs that can have resolutions over 30
megapixels.

EDIT: added “why” at beginning

~~~
welly
Why do people use hand saws and chisels when powered table saws, compound saws
and biscuit joiners are available to us?

As someone who shoots film, there are a number of reasons, one being the
asthetic you get from film that you can't (even with x hours in Photoshop) get
from digital. I shoot large format and there are no (within my budget, at the
very least) 8" x 10" digital sensors.

Film also more or less forces you to make prints. I would hazard a guess that
a small percentage of digital photos ever make it to print and half of a
photograph for me is a tactile thing you can hold in your hands and give to
someone else.

Lastly, it's the process. That's something I can't explain.

~~~
mark-r
An 8" x 10" digital sensor would take a whole silicon wafer. Doubt you'll see
one, ever.

~~~
dahart
The LargeSense LS911 features a single shot 9×11-inch monochrome CMOS sensor
with a 75-micron pixel size, a high base sensitivity of ISO 2100, and a
maximum sensitivity of ISO 6400.

[https://petapixel.com/2018/04/17/largesense-unveils-
worlds-f...](https://petapixel.com/2018/04/17/largesense-unveils-worlds-first-
single-shot-8x10-digital-camera/)

~~~
gcp123
This thing only shoots 12mp images (and only in black and white). Nothing like
what you'd get from an actual large format film camera.

~~~
mark-r
You can turn any black and white camera into a color camera by taking 3
pictures with a red, green, and blue filter. Obviously only works with a
static subject.

I must admit 12MP is lower than I expected. It seems the intent was to use
large pixels to get huge tonal range rather than small pixels for resolution.

------
Finnucane
Ilford has been warning about this also. Previous generations of scanners were
generally okay for film up to about ISO 800, but these new scanners are
believed unsafe at any speed.

------
JustFinishedBSG
Can wait until very important data is lost to bit flips / corruption from
scanner.

" Cure to cancer lost to TSA scanner "

~~~
ChuckNorris89
If you're working on a cure for cancer you should have double, triple,
quadruple backups on and off site and not fly around with the only copy of
your data.

~~~
harikb
I bet GP meant it to ironic. That said, having a backup and knowing that the
data was just corrupted are two different things. In a word without storage
level CRC checks, it is possible an otherwise successful test is overlooked
and we move on to 'n + 1' in the iteration.

But that said, hopefully all filesystems have some sort of error to show the
file has been damaged.

------
coldcode
If its bad for film, would it not be bad at some level for people?

~~~
colejohnson66
This is for the checked luggage, not the people scanners.

~~~
cguess
It's for carry on. Checked luggage goes through WAY more radiation and you
should never put undeveloped film or anything else that's radiation sensitive
in your checked luggage.

~~~
morsch
Details:
[https://hps.org/publicinformation/ate/q12361.html](https://hps.org/publicinformation/ate/q12361.html)

~~~
tbihl
For reference, 300-350mrem is a decent estimate of your annual dose of
radiation. If you fly a lot, smoke, or live in areas where the ground releases
significant amounts of radon, your own annual dose can be twice that.

------
hosteur
What about those full body scanners? I always opt out due to health concerns.
Does anyone known anything about the actual radiation levels involved in those
and the safety standards the machines must live up to?

~~~
dijit
I know a lot about them; I researched them extensively even to the point of
talking to designers.

I came to the understanding that they're quite harmless; even considering the
radiation doses you get while flying after (because, radiation is additive of
course)- However using them many times per day can cause damage to the skin
over long periods of time.

Regardless, Opt out anyway; if people choose to opt out the economics of the
devices will stop making sense and perhaps they'll be a little less invasive
in future.

I will always opt-out, even when I'm being threatened or condescended to (as
was the case in Gatwick airport some time ago).

