I really thought it was 7-segment LED but he made a point that making 7-segment LED that tiny in 1990 was a challenge, not some technology you casually put in common $30 devices. this mini projector is the perfect solution for the job, really clever and kudos to the inventor. And not mentioned in the video is I think the bulb draws energy from AA battery source instead of CR2025, correct me if I'm wrong.
Joran Groothengel When he bought a new Tesla just because he needed new tires because they were never rotated was when I really lost hope in that channel.
Just to put a few things correct: The Base Colour is not orange: The orange Mask is formed during development and not present prior to it (and it is not uniformly... rather its density depends on the amount of exposure in the area.) The base is usually transparent or of a neutral grey colour. The reason that the numbers are red/orange is a result of two things 1. The sequence of the colour sensitive layers and filters in the film and 2. Only the red layer is sensitive to red light. From the emulsion side to the base the order of sensitive layers (SL) may look like this( there can be more layers but in general it is this sequence): blue SL -(filter passable for green+red light)-green SL-red SL-Antihalation layer(AHL). So why are they red? As it comes the AHL blocks a good part blue and of the green light of reduces the red part (it depends on the manufacturer and what dyes they use). If exposed through the base the light has to travel through the AHL (prevents light piping through the base) and then the red sensitive layer and then the green sensitive and then the blue filter), since the residual light lacks any blue the result are red orangey numbers. The AHL dyes are washed out during development and are never to be seen in the developed film. Anyway film is extremely complex, it is quite interesting what sort of knowledge is needed to make it...and how sensitive to certain things it is.
In the basement at Kodak Research Labs they used to have a secret (known only to the local fire DP at the time for emergency situations) subcritical nuclear reactor that used highly enriched weapons grade uranium and californium (ie. a neutron multiplier) just to produce a neutron beam so they could neutron activate random test lots of film and examine the trace element and even isotopic composition of the product for consistency. The technique was so insanely exquisitely sensitive they could detect the seasonal change in diet of a certain flock of sheep kept specifically for the purpose of producing a tiny trace additive (from the wool if I remember right?) to one of the film base's secret ingredients. THAT'S how complex film production was.
10mintwo , didn't know that Kodak checked their film with NAA. Something related to this: in 1925 a Kodak emulsion engineer found that if a cow ate mustard seed, the gelantin produced from it increased the film speed.
In addition most C41 negative film was daylight balanced (white balance in today's digital cameras) which is 6500K; on the other hand that tiny incandescent bulb is probably about 2000K - and therefore yellow-oragne-ish.
I was thinking that the reason for the amber colouring might well be explained by the fact that the light source is an incandescent bulb: when you turn it on, it doesn't just immediately produce white light, it ramps up through the wavelengths as the wire (relatively) slowly heats up. The same is reversed when the bulb cools down. Thus the combined dose over time, i.e. the exposure has a portion of it in redder hues. I don't know if the warm up/cool down time in the cycle is significant enough to actually make any difference, but this was my first hypothesis.
NEY Industries it’s helpful for things that need the date and cannot be easily reproduced. For example, police recording evidence and also need to record when that evidence was found
Back in the mid 80's I worked for a company as a machinist that made alphanumeric data backs. A row of micro LEDs were set flush to the backing plate and they fired when you advanced the film. The system worked much like a dot-matrix printer. We used a TRS-80 Pocket Computer to input up to 40 alphanumeric characters of text. We mostly sold our system to police departments and federal agencies. Thanks for the video...
Fascinating breakdown. Never occurred to me how that date got on there. Now seeing the breakdown I’m really impressed with engineering involved to get that date to show.
I love that this was from back in the day when there were still screws to remove. These days it more likely than not would be one ultrasonic welded hunk of plastic that you'd have to destroy to get into.
I teared down a "new" film camera from the 2000's (kodak aps) to re-use the photoresistor in an older , easier to repair film camera and you are completely right, it was easier than items from today but not as easy as the old camera
I've taken apart several modern cameras, and anything that wasn't an ultra cheap trash camera is put together with plenty of screws and clips. No fused plastic 'rivets' or much glue at all. Everything from Nikon Coolpix L20, various small Fujis, an HS50, small Canon A480, ,G15, Canon 7D MK 1 and 2, not to mention several no name brand Chinese cameras. All perfectly disassembleable, repairable and reassembled without much fuss. Though it does require patience, a microscope and steady hands. Some soldering also required to disconnect ribbon cables.
If you flip film around and expose it through the back, it shifts everything red too. A few companies like Lomography sell film that was re-rolled the wrong way to get the effect--called redscale. The red dye layer is also the last layer that light hits with color negative film.
This is based on the fact all silver halides are sensitive to blue light. If exposed correctly, the blue light would be filtered out after the yellow (blue sensitive) layers, When exposed from the back side, this is not the case.
I honestly never wondered how this was done but I am now glad to know and I wonder why I never wondered because it is pretty fascinating and unexpected . Thanks for sharing!
This reminds me to when I found an old photo camera in my grandmother's home, which I took to bits, because my grandmother didn't need it anymore and affordable digital cameras already existed, because it was back in maybe in 2006 or 2007. I also found such a tiny LCD-screen, which I instantly new, that it was for the date "printing" but I don't remember if it was located at the back of the film or in front of it. What I find amazing btw is that analog photo film develloping services still exist here in Germany in some supermarkets considering that digital cameras are now omnipresent these days. You can also find such tiny LCD-screens in projector alarm clocks. I got one for about 1€ on a flea market and took it to bits and found an LCD-screen of a similar size.
I clicked this thinking, "Man, a fourteen-minute video on camera date superimposition? This is going to have a lot of fluff in it," but much to my surprise, this entire video was useful and engaging. Thanks for the interesting teardown.
If you think about it, the shadow projection (so how this masks off the areas around the numbers) is only suitable for close projection. The further away the little screen would be the blurrier the numbers should be until they are essentially invisible.
This is wonderful. All the steps to figure out each element were fun to watch. I am glad I watched until the end, because I kept wondering "wait, the date display is BEHIND the film!" Fun video!
This reminds me of the scene in _Alien_ where Ripley is accessing the MU/TH/UR 6000 computer. It shows a projection of the screen on her face, but when I think about it, there's no way that she could read the screen that way.
2001 has a similar scene in the close-up shot of Dave in the pod. That's a fairly common trope in movies with computer/radar screens and it always bugs me. tvtropes.org/pmwiki/pmwiki.php/Main/Cukoloris
I recently brought an old date back camera which is the same type my mum used when I was a kid. Unfortunately, after the New Year Eve it turned to 1980 instead of 2020 and I really want to hack the little piece to extend the limit of date. Camera with date printing back has special meaning to me and I will look forward to your following videos.
Intriguing teardown, thanks for showing how it works. Regarding mechanical film timestamping the Databack has precedents. During WWII and after, some aircraft photo reconnaisance cameras had timestamping on the film. I have one such camera, it's a british Air Ministry Type F46, 5" focal length lens taking a 2"x7" negative, running on 24 volts. On the bottom face of the camera body casting at the righthand side is a small box housing (labelled 'F46 WATCH UNIT' and A.M. number) that can be removed by sliding off. Inside is some black felt and a circular cutout for a tiny fob watch of no more than 1" diameter. Inside the housing body where the box attaches there are two festoon light bulbs to illuminate the watch face, and a 45 degree mirror and light pipe extended to the corner of the film plane to record the time of day the photograph was taken.
Such a cool teardown, thanks! There's another thing about the date always being orange: colour film actually consists of several light sensitive layers, each sensitive to different light. The layer closest to the base of film -- and, therefore, the closest to the date imprinting back -- is sensitive to red light. So, when the light hits the film, it hits the red-sensitive layer first, which makes it this reddish colour. The same effect is sometimes done on purpose: the film is rewound the other way around, with base towards lens and emulsion towards the pressure plate. The resulting pictures are a reddish colour, much like the date on the photos. As a result, this is called "redscale". I suspect that with redscale film, the date would actually be white.
Thanks for feeding my curiosity, Ben :] I'd never thought about how that works until now. Really quite interesting to see an LCD and incandescent bulb working together.
I feel like only us old guys can really appreciate this. That time stamp was a revolutionary process in photography. Amazing that we find out 25 years later how it worked...
@@weithiamneo1442 I can't predict much about the cost of film, but development is - and most likely will still be - dirt cheap and you can do it at home. In a pinch, you can even process a C41 (color) negative in ancient (created in 1890s) Rodinal, or even coffee (google: caffenol processing). Of course by doing that you only get black & white pictures, but hey, that's still analog photography, with the added fun of experimenting!
@@among-us-99999 Analog photography traditionally means using analog medium (photosensitive film) to capture images. The control electronics don't really matter much - a roll of 35mm film would work the same way in 1925 Leica and in 2018 Canon EOS-1V. Now that's some serious backward compatibility!
“Red scale” is a process by which film is flipped and exposed backwards (colour neg), and this gives a red tint to images. This is due to the order in which the colours are layered: longer wavelengths penetrate deeper, so red is always the closest to the base of the film. This is why the numbers have a reddish tint.
This was very cool! I'd never thought about the mechanism of the date display on a film camera. As a kid one of my favorite things to tinker with were disposable instant film cameras that I had gotten for free from my local drug store. They were this really cool mix of mechanical parts and electrical circuitry, all under the influence of cost-optimization which resulted in a ton of simple, yet genius design choices. Due to being disposable these cameras did not have the date display feature present in this model so I'd honestly never thought about it since the cameras I had on hand to explore did not have the feature.
This is incredible. Would never have thought such complexity lies behind such a tiny result. Makes me think about all the crap around me and all the years of scientific and engineering iteration and progress that led to it. Mind = blown.
So awesome. Thanks for doing this and finally satisfying my inner childhood curiosity. Some great creative engineering to a price point to make this happen. No way I could afford to disassemble my film camera when I was young to figure this out!
I owned a Ricoh camera with this feature. Given the LCD tech at the time and ‘reverse’ LCD displays, I figured this was the setup but it’s still so cool to see it taken apart.
I have seen the dates in old photos but never thought the process would be so fascinating 👍 Wonder how many more fascinating processes I miss everyday.
More film camera tech please, there is so much outdated and cool tech that we are forgetting about in these. I use film cameras partly because i love the amount of engineering and sophistication that goes into these compared to all computerised based systems that we have nowaday (still cool but you can't really see it)
Computers just make things too easy. (I say that as a developer of both electronics and software) Analog is always so cool because they really have to go for reduced complexity just to make it work, fit, be cost effective....etc. Nowadays just throw a $3 mc that you use 10% of it's features in an unoptimized fashion and it still provides more power in smaller space and less intricacies of the product. (Not the mc, what it's used in)
@@GRAYgauss Nothing easy about computers. Sure they're mass produced, but they're the most complex and delilcate devices ever created by man. Economies of scale result in the $3 board. Sure, it's neat to see mechanical devices that got it done in the past, but there's way more engineering done on the computerized side to get it working like it does.
Can agree, my oldest camera dates from 1957 (amazingly I have the original box too!) And there's just something amazing about the fact no electronics are used to get a picture. That camera would go through an EMP and be unphased by it. If curious what camera, Argus C-20. It's an updated version of the C3 from what I could find.
y2keable I'm not saying film photography is outdated ! I am using film cameras most of the time over my DSLR. I just love the fact that when all of our modern life revolves around computer science, it is still possible to make a great looking image using only analog technology, good mechanical and optical design and some chemical emulsions. So in a sense it is outdated as little to no development is done on new film cameras.
Amazing technology. I used to have a Konica Minolta camera during 1993-2000 and I have prioritized it over then hot favorite Kodak film cameras because it has date and time stamp feature. Although I paid few buck more, it was a big amount in those days. When I purchased digital cameras I disassembled the Minolta one and kept its back door (containing date/time lcd) and its flash with charging circuit and a big capacitor. All is still in my junk box.
That's great!, thanks for showing this, i still takes pictures in old cameras with film and this was super interesting. The reason for the white light turning out red shifted on the film i think it's because of the composition of the film itself, which has 3 color layers i think being the last one (the closer to the back of the camera) the red one, which is the first layer that hits the LCD projector. There's a whole artistic technique in old photography called Redscale which makes use of this property of the film, the film is put on the camera inversed, so the red layer is the first to receive the light coming through the lens and produces red toned photographs.
Thanks for the superb video. I have a Canon A-1 which I purchased in 1979, and it came with the data back, much like the Nikon except the wheels were not interchangeable. The whole data back came off as the back of the camera and the cable ran into the sync port on the camera, so the date would be applied whenever the shutter was tripped. There were three intensity settings based on the ASA of the film you're using. The light emitted was a bright white, and this resulted in at pleasant Orange image on the film. As I recall it used its own Mallory PX -28 6V battery, which is what the camera also used. Past memories, thank you
Finally a question i can answer @ 12:45 @appliedscience The date appears red because of the chemical emulsion in the film, there are 3 types of chemical in a film layered up over each other. Normally, when you shoot the film "correctly" the blue sensitive layer is up front, then comes the green one and then the red one. But if you shoot the film flipped, the red sensitive layer is the first one that is exposed to the light, some photographers even shoot photos like this intentionally to give the film a red look, that's also why this style of shooting is called "red scale". And thats exatly what happens here, the photo is still exposed the right way, but the data back exposes the film from the other side hence it appears red/orange.
Perhaps that could be something I can try to film. Have an old camera from 1957 that's 100% mechanical, and it's a good camera to demonstrate fundamentals on (and in fact, is how I learned the fundamentals as I grew up after the film era lol)
I actually got interested in this and looked it up. I think (you probably already know) Akihiko Hashimoto from Olympus is the man behind this innovation with holding a 1978 patent US4232956A.
No three-minute introduction, no thirsty valediction, the video is exactly what the title says; oh, and it's interesting! You hit the quadrifecta, sir.
Great video, showed exactly what it promised. This is a great example of a video where dislikes do not make any sense; seriously, why would someone dislike this video? It showed exactly what it said it was going to, and even when into detail about the components.
Very cool! Never even considered how it got on there! I wish all negatives had a way to encode time stamp to get placed on the back of prints or optionally in cleaner font superimposed on the image like with APS magnetic. It would save me lots of research time when trying to add dates to massive photo collections
Amazing! There are tiny rectangular cut outs on the PCB along the light path which I guess are meant to avoid internal reflections on the green PCB material by letting the light pass thru and then be absorbed by the black plastic case. Great video on an apparently trivial subject!
Hi there, 1st of all thank you for this video it was fun and beautiful to listen and watch everything. I work as a senior laboratory technician at Academy of arts. And actually I work a lot with celluloid films and analogue photography. I just wanted to answer on your potential question about color of date imprinted on photos. If I'm right the logic would be this: the reason why the color is red or orange is actually connected to bulb color temperature (kelvins). If you look carefully the light is orange and when it projects on film you will get inverted complementary color cyan (that is all in negative) when you invert negative to positive, than again you will get complementary pair of cyan - orange. So the reason why all the dates are orange or red is actually depending on light temperature of bulb. If you change bulb color, you would change also color of imprinted date.
Very nice. The long light path to the LCD also adds in the inherent ability to not have a focal plane, as the distance from the LCD to the film will vary slightly due to temperature and the back of the camera moving slightly, yet the superimposed date is always going to be sharp as it is a shadow, and not formed by a lens. Only variation from changing back position is a slight change in image size, and that is a much smaller change compared to having an out of focus image. As to the slower update of the LCD, that probably is also due to the polarising filters and thicker fluid inside, to get a denser image contrast. Plus there is also probably a IR cut film applied to the one side, as the IR from the lamp would bleed through the LCD anyway, due to the long wavelength, so you would need some form of coating to either reduce this, or the front surface mirror is dichroic to not reflect the IR onto the LCD.
The moment you mentioned it projects light on to the film, I said to myself "Wait, how does it use only light to make the numbers on the film?" The second you mentioned how everything needs to be absent of light, or it'll ruin the film, I realized the light it projects through is specifically ruining only that small section of the film to MAKE the numbers! So what we're seeing on a photo is in essence a section equivalently "scratched off" as if you were removing only part of a tint off a tinted window. It's so simple, yet cool. I just assumed this whole time it was digital, even back then.
Thanks for the video! The color makes sense since the date stamp is being exposed through the base of the film exposing the red-sensitive layer. An incandescent bulb being mostly orangish (3200k) would be less likely to leak wavelengths to the other layers even if the intensity was bright enough to make it through. The numbers should appear magenta in color on the negative. Never really thought about it before...
RU-vid recommendations are on point again. I think YT knows me more than I know myself. Never knew this channel existed but Its exactly in line with my interests! Will be looking at other videos on this channel... thx RU-vid ..
hi! thanks for great review! it is very impressive how people figured out this cheap way to project the date stamp on the film. I just want to add that red shift in the projected colour related to the fact that consumer cameras these days always turned white balance of in camera settings to get neutral look, so most of the shots were in daylight above 5000K, incandescent light is 2700K will always appear red or orange. in case you could adjust the colour temperature to 2700K, the date stamp will appear white coloured.
You are correct, if the time stamp projector would have been projecting through the front of the film. If you expose film through the back, everything gets a reddish hue because of all the different emulsion layers you're projecting through. Lomography made a 'redscale' film that is just normal film, spooled onto the reel in such a way you expose it through the back. The emulsion consists of 4 to 12 coats in color film IIRC.
Great video. The explanation for the amber hue of the numbers is actually pretty simple. The film that 99% of people used was daylight balanced for approximately 5500K the incandescent bulb shown in the display is closer to 3000K therefore will register as a warmer hue. You could get tungsten balanced film but it was much harder to come by and much more expensive. It was only mainly used by professional photographers, and more specifically those who did high end architecture, advertising, etc. it was typically denoted with the letter T at the end of the ISO rating. If you used a T rated film the numbers would have appeared almost stark white instead of amber. Hope this helps.
Regarding the color of the film. Teton Gravity Research did a documentary about how they started and one of the mistakes they made early on was to load the film backwards..and guess what..all resulting images were red. I love this kind of engineering - simple system with a lot of thought behind it.
the exact second when you pointed out that the exposure of the date came from the back my brain said "yes, of course" - because I have also wondered about the color of the imprints. I myself always found these date imprints annoying and irritating - a better system would have been to imprint it on the unused side strip of the negative or between the frames so that later at the lab it could optionally be superimposed onto the image or perhaps be printed on the back. Some film manufacturers used the side strip for additional information like brand name and negative-number, but the spac between frames was always empty.
I never even thought to wonder since the age of five this conundrum, but once I saw the title of this video I had to know the answer to this long forgotten yet burning question!
There's nothing unusual about LCD being all black, with translucent digits. It's just the way the polarizing film is oriented. During the early dot-matrix LCD era of mobiles, people would "hack" their displays by removing the polarizing layer and re-applying it rotated 90 degrees, thus "inverting" the display. Great vid, btw.
I guess I never thought about it too much as a child or just have forgotten all about this mystery, but I’m glad I know now. Thanks and I would have never stumbled upon this video if I didn’t recently buy this canon a1 film camera that had this unusually large back door (data back a) and was curious enough to search it up on RU-vid
9:42 If you notice it had other slots for mirrors to go in, with the matching holes in the circuit. Therefore I'm assuming they could be fit for different film sizes by just changing the mirror position and the back plate, that has the lcd fixed after this position. Cool.
