
Thermal Paper Polaroid - Ivoah
https://mitxela.com/projects/thermal_paper_polaroid
======
joezydeco
Just a friendly reminder that most common types of thermal paper contain BPA
or BPS. You really should be avoiding these endocrine disruptors when
possible.

[https://www.pca.state.mn.us/green-chemistry/bpa-thermal-
pape...](https://www.pca.state.mn.us/green-chemistry/bpa-thermal-paper)

~~~
Justin_K
Why must every post on HN have a (surprisingly) high ranking post just
crapping all over some aspect of a project?

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lifeformed
It doesn't feel like it's "crapping all over" the post - it's just a off-hand
safety tip that isn't judging anything.

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DanBC
It's off topic, mildly tedious, and yet it's somehow stuck to the top of the
thread while more interesting posts are buried below it.

~~~
lifeformed
The thread positions aren't exactly sorted by most-upvoted to least, a lot of
new comments end up on top.

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chrsstrm
Very cool. I made a Pi thermal printer photobooth almost exactly two years ago
that worked on the same principle, although I wasn't crazy enough to try and
cram it into a Polaroid shell. What seemed like a simple exercise turned into
more research than what I thought I had tolerance for on a side project. IIRC
from my experience there were two big problems: 1. versions matter when it
comes to printer drivers, OS, and your hardware combo, and 2. the data buffer
on thermal printers is not big enough for what you want to do (which is why it
spits out random chars and symbols instead of your photo). The printer I was
using had a buffer pin but ultimately I was short on time and patience so I
opted instead to use imagemagick to convert and compress the photo before
sending it to the printer. I used the booth for my nephew's birthday party and
it survived real world use pretty well. You got a nice physical souvenir (I
also added a "Happy Birthday" \+ date overlay to each image) and I set up a
local server on the Pi that let people browse the digital versions of all the
photos with a framework called Sigal. Very fun hardware project and I intended
to publish a writeup outlining all the sharp corners I navigated but never got
around to it.

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js2
> Long before the final assembly I'd wired the little LED under the viewfinder
> to one of the pi's GPIO. I'm not sure what it originally represented...

From the manual[1, 2]:

 _When you are not using flash, a red light may appear under the viewfinder as
you begin to press the shutter button. It warns that the lighting on the scene
is not bright enough for picture taking without a tripod or other firm
support._

Also, this bit from the manual is somewhat amusing given the extraordinary
chain of events occurring inside the hacked camera:

 _As you begin to press the shutter button, your camera releases sound waves
to the central part of the scene. The frequencies are far beyond our range of
hearing and travel at the speed of sound. The split second it takes for the
sound to reach your subject and the echo to return is fed into a tiny
electronic computer inside the camera. The computer uses this time measurement
to calculate the distance between the camera lens and your subject, then
signals a motor to turn the lens until your subject is in sharp focus. This
extraordinary chain of events takes place in less than 1 /3 of a second._

[1]
[http://www.cameramanuals.org/polaroid_pdf/polaroid_sonar.pdf](http://www.cameramanuals.org/polaroid_pdf/polaroid_sonar.pdf)

[2] Found via [http://butkus.org/chinon/](http://butkus.org/chinon/) which
itself is a lovely 1990's style web-site. I couldn't help but donate $3.

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Lanthanide
Makes for a much more in-depth and capable version of the Game Boy Camera +
Printer:
[https://en.wikipedia.org/wiki/Game_Boy_Camera](https://en.wikipedia.org/wiki/Game_Boy_Camera)
an object of gadget lust for me when I was growing up

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Nexxxeh
I had the camera as a kid. Ben Heck did some interesting reverse engineering
on the printer, and there's some stuff on Hackaday too if you're interested.

~~~
Lanthanide
Thanks for the headsup, love Ben's stuff but I haven't caught up with it in a
long time, I'll be sure to check it out.

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anilgulecha
I built pretty much exactly the same thing, but without the polaroid camera
shell, but did not get around to writing about it. A couple suggestions:

1) Apply exposure compensation and dithering to the image. this allows a
better fidelity output. Example:
[[https://i.imgur.com/eCLRs8Q.jpg](https://i.imgur.com/eCLRs8Q.jpg)] you'll
have to play around with the exposure depending on the camera you're using.

2) the 3" paper printer would make for a much better output than the 2" one,
simple because the former is closer to an actual photo size.

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vardump
This chapter was funny.

"Cut the USB

With time running out and no better option in mind, I broke out the cutting
disks and surgically removed one of the USB hub circuits from the 7-port hub."

Regarding his earlier rant about USB hub quality, I have to agree. It's
getting harder to come by a robust USB hub nowadays. Bad connector and power
supply quality (USB hub PSUs are electrically noisy and way under powered for
the number of ports).

~~~
nikanj
There are two kinds of USB hubs available nowadays:

1) Cheap Chinese crap

2) Cheap Chinese crap, in a fancy, expensive designer enclosure.

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jimnotgym
Why I love Hacker News. I read an article about a cool hobbyist project, and
my mind leaps to someone at work was having trouble with a thermal printer...
and I just realised what the fix for their problem is...a total tangent but
that often happens.

I love the idea btw. My wife wants one already.

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lwansbrough
I kinda like the concept, too. Beyond just the whole execution, which is
really well done. Thermal paper disappears over time. So this in turn means
these photos are somewhat ephemeral. I haven't lived long enough to know
whether I prefer photos or pure memory, but I have to assume there's something
redeeming about relying solely on your memory.

But I also love that my children one day will be able to see perfectly
accurate photos of myself in my 20s, whereas photos of my parents + their
parents have considerable wear.

Anyway, love this post. Thanks for sharing!

~~~
PickledJesus
They've been noticeably degrading for a while already in fact, and are getting
worse. [https://i.imgur.com/Qmmqs3E.jpg](https://i.imgur.com/Qmmqs3E.jpg)

~~~
egeozcan
is it possible to prevent or reduce the degradation with a frame or some other
protection?

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b5
At an old temp job I had, my manager, much older than me, habitually
photocopied faxes as they were received precisely because the thermal paper
fades over time. Even stored well, in the dark, in a dry box, they'll
gradually fade over time. Leaving them exposed to the light will fade them
really quickly.

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dghughes
Just an FYI regarding thermal paper and highlighter pens.

At a former job some of the staff were printing some free product vouchers. On
each they highlighted certain data to make it easy to spot. Well they soon
found out that a highlighter on thermal paper will erase what is highlighted.
It takes some time but it does a great job of erasing it. I don't know how or
what the chemical process is but it does work, or fail, whatever your goal was
I guess.

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duiker101
Not even in my wildest dreams I would have imagined that today I would have
ended my day browsing Amazon for a thermal printer.

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amiga-workbench
i have been looking at them on ebay for about 20 quid. i wanted one for the
office for printing wifi guest access tokens.

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anfractuosity
I'm wondering could you sort of use thermal paper directly with a lens and a
long enough exposure to directly create an image on thermal paper?

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michrassena
Does thermal paper darken if left in the sun? If not, I don't see how a
projected image will be hot enough to burn an image. Even if it warms up the
paper, the process has to happen fast enough that the heat isn't conducted to
the surrounded area first. Maybe you could make a solargraph with thermal
paper, where the sun burns a path over many days.

Typical photographic paper (developed in the darkroom) or direct positive
paper is better suited to what you're suggesting.

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throwahey
Oh wow, I remember this guy from ages ago on an old Zelda forum. The internet
really is a small place. Great post!

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antigirl
what do people talk about in those?

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gaze
I wonder if there’s a better cheap thermal printer than receipt printers. The
thermal printers used in ultrasound machines seem really nice.

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romwell
This is an awesome project!

Also, for those unaware, people at Polaroid thought so, too, and released a
thermal-printing color Polaroid SNAP a few years ago. It makes prints
comparable to Fuji Instax, but the camera is digital and pocketable.

I've owned it for a couple of years, and I call it the friend-maker camera.

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dmix
He says in the video you can’t buy one but I recently bought a Polaroid camera
as a gift at Urban Outfitters for $100, plus the expensive film ($30 for 8
shots) that goes with it. Is this different in some way?

~~~
khedoros1
Polaroid themselves stopped making the cameras and film. "Polaroid Originals"
is a Dutch company that bought Polaroid's instant camera brand and IP. They
were previously trying to re-create Polaroid instant film on their own, I
think (or they'd bought one of Polaroid's film factories, or something?)

Anyhow, I think they're the ones producing film now, refurbishing old Polaroid
cameras, and also selling their own model.

~~~
Jaruzel
Polaroid Originals were originally called 'The Impossible Project' and was a
kickstarter campaign based around recreating the original Polaroid Instant
film.

It ended up being so successful, that they managed to acquire the brand name
and IP of Polaroids Instant Camera technology.

I'd link to a source, but it seems that [https://www.impossible-
project.com](https://www.impossible-project.com) now just redirects to
Polaroid Originals.

~~~
toomanybeersies
They didn't buy the IP for the chemistry for the original Polaroid film
though, as Polaroid sold that to Fuji.

That's why there's only 8 instead of 10 photos in a pack, because their
chemistry required thicker photos, and the photos take about 30 minutes to
self-develop, rather than 30 seconds of original Polaroids or Fuji Instax.

~~~
khedoros1
That makes sense. Fujifilm was the other brand of instant camera+film that I
saw when taking a quick look around.

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kiddico
The USB hub pictures made me giggle. I've had to fit USB hubs in some odd
places, but never had to chop one up quite like that.

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ghazak
This is hardcore

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GuiA
This is fantastic work, and the final pictures are wonderful. Instant cameras
immediately make everyone happy.

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AnnoyingSwede
Nice build, loving it!

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cjsawyer
That was fun and informative!

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ggm
Ace!!

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transistor-man
beautiful build!

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billyt555
Great work!

