[HN Gopher] A look inside the chips that powered the landmark Po...
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       A look inside the chips that powered the landmark Polaroid SX-70
       instant camera
        
       Author : picture
       Score  : 88 points
       Date   : 2022-02-10 17:33 UTC (5 hours ago)
        
 (HTM) web link (www.righto.com)
 (TXT) w3m dump (www.righto.com)
        
       | riffic wrote:
       | there's a charles and ray eames promotional film about this
       | camera.
       | 
       | https://www.eamesoffice.com/the-work/sx-70-polaroid/
       | 
       | Watch the film:
       | 
       | https://youtu.be/zpv8J8e9gWI
        
       | yardie wrote:
       | I'm impressed that surface mount components existed in the 1970s
       | and in consumer electronics that early. I've taken apart VCRs and
       | game consoles from the 80s and they were DIP mounted and through-
       | hole circuit boards for all of the ones I've come across. I
       | didn't realize the SX-70 was so cutting edge.
        
         | dboreham wrote:
         | I believe they always existed, but were not widely used until
         | the late 1980s when pressure to reduce size and cost became
         | dominant and pin counts on packages rose above the limit for
         | DIP. I worked in the industry at the time and remember the
         | transition. You had to ask assembly houses if they had reflow
         | capability, automatic pick and place, etc, otherwise they
         | couldn't manufacture SMT.
        
         | unobtaniumstool wrote:
         | I was surprised by that too. I took apart a lot of electronics
         | as a kid and distinctly remember it being mostly components
         | with leads.
        
         | kens wrote:
         | Texas Instruments' surface-mount miniDIP chips were "new and
         | risky but cheap", and one of the innovations that made their
         | second design of the Polaroid circuitry successful. Aerospace
         | had been using a lot of surface-mount in the 1960s, e.g. the
         | Apollo Guidance Computer. But consumer electronics didn't
         | really use surface mount until about 1990. I've wondered if
         | there was any particular reason surface mount wasn't popular
         | sooner.
        
           | buescher wrote:
           | I first saw surface mount parts in a camcorder viewfinder -
           | flea market find - I picked up in 1985 or 1986. I don't think
           | I even read about them until the 90s otherwise. I was
           | surprised the first time I found out how far back they went.
           | There must have been a huge chicken-and-egg problem involved
           | in bringing them to the mainstream.
        
           | monocasa wrote:
           | Do you know anything about the manufacturing process? I
           | always connect most of the benefits of surface mount with
           | reflow soldering and pick and place machines. I doubt they
           | used pick and place in 1972 for consumer goods, but maybe you
           | can just have assembly line workers placing by hand before
           | before the line runs through a reflow oven?
        
             | buescher wrote:
             | There's such a thing as a manual pick and place machine. I
             | agree, though, it would fascinating to know how these were
             | assembled.
        
           | ghaff wrote:
           | I never knew that aspect of the AGC. I knew the core memory
           | was "sewn" by women at Raytheon but I wasn't aware it wasn't
           | just standard core. The guy who ran software at the
           | Instrumentation lab (and had literally written the book on
           | orbital mechanics) did once give a talk where he related an
           | anecdote of some of the astronauts visiting Raytheon to, as
           | he put it, reinforce that they should really be careful lest
           | these nice young men die.
        
           | mulmen wrote:
           | The AGC is a fascinating device. It used 60% of the ICs
           | produced _in the United States_ in 1963.
           | 
           | If you are interested in the AGC I suggest this excellent
           | video: https://www.youtube.com/watch?v=B1J2RMorJXM&t=454s.
        
             | morsch wrote:
             | I think he has, in fact, shown a passing interest in the
             | AGC in the past. ;)
             | http://www.righto.com/search/label/Apollo
        
               | mulmen wrote:
               | Haha! I didn't look at the username!
        
       | kens wrote:
       | Author here for your Polaroid camera questions :-)
        
         | jdkee wrote:
         | Will you be investigating the sonar system developed for later
         | cameras such as the SLR 680?
        
         | s800 wrote:
         | So the integrator circuit implies it determines the exposure
         | time during the exposure? Meaning, the metering is ongoing
         | during the shutter opening?
        
           | kens wrote:
           | Yes. It's a pretty clever circuit. You can think of film as
           | integrating the amount of light that falls on it, so the
           | photodiode integrator is computing the same thing. So the
           | film will get enough light at the same time the integrator
           | gets enough light. By closing the shutter at that time, the
           | film is properly exposed.
        
           | foldr wrote:
           | The Olympus OM series had some particularly ingenious
           | integrative metering modes, including metering light
           | reflected off the film itself.
           | https://www.dpreview.com/forums/post/24653220
        
             | [deleted]
        
         | ravila4 wrote:
         | I have a couple of these cameras. How difficult is it to get an
         | OpenSX70 circuit PCB printed and installed? Is this something
         | achievable by an average tinkerer?
        
           | kens wrote:
           | I don't know the details of the OpenSX70 boards; I just
           | looked at the Polaroid chips :-)
        
       | anonymousisme wrote:
       | The film packs included the (flat) battery, and the (non-
       | rechargeable) battery always had plenty of charge left after the
       | film pack ran out. I salvaged those batteries and used them in
       | many electronic projects.
        
         | polpo wrote:
         | Polaroid even capitalized on this a bit - they produced a radio
         | that ran on the batteries in spent film packs in the 1980s.
        
       | Koshkin wrote:
       | As a programmer, electronics looks like fun. (After dealing with
       | all kinds of thick and dense infrastructure stacks, it's
       | refreshing to see how things work at the lowest level - where the
       | "stack" below is just Nature herself.)
        
       | junon wrote:
       | "Instant camera" is a phrase I haven't heard in what feels like a
       | lifetime. Amazing how quickly they lost prevalence.
       | 
       | Hearing it feels like a fever dream, I had to question if I knew
       | the phrase at all.
        
         | gkop wrote:
         | FWIW they are still a thing:
         | https://duckduckgo.com/?q=instant+camera&ia=shopping&iax=sho...
         | 
         | My subjective, anecdotal sense of trends is that instant
         | cameras were big in the 80s, faded in the 90s, and made a small
         | (but sustained) comeback in the mid-2010s.
        
           | ghaff wrote:
           | The dates will differ but a lot of things (think vinyl
           | albums) probably follow some sort of mainstream, obsolete,
           | retro lifecycle.
        
           | stickfigure wrote:
           | These were common at Pivotal when I was last there. Everyone
           | gets a snapshot for the pairing board. I bought one and did
           | the same thing at my last company.
        
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       (page generated 2022-02-10 23:00 UTC)