[HN Gopher] DIY Camera Using Raspberry Pi
___________________________________________________________________
 
DIY Camera Using Raspberry Pi
 
Author : the_arun
Score  : 145 points
Date   : 2021-04-19 04:18 UTC (18 hours ago)
 
web link (ruha.camera)
w3m dump (ruha.camera)
 
| dheera wrote:
| I _really_ _really_ _really_ wish RPi would come out with a
| _real_ HQ camera with at least an APS-C if not 36x24mm sensor.
| This dinky little IMX477 sensor is MQ, not HQ.
| 
| The uses would be endless, ranging from astrophotography to real
| professional-quality shots with homemade, scriptable cameras;
| shots synced with high-speed motion; a whole new era of homemade
| SLRs and mirrorless cameras that are actually competent; lots of
| things I can think of.
 
  | bmurphy1976 wrote:
  | Also fix the interface so that you can actually record 4k
  | video. The sensor is capable but the interface is not.
  | 
  | https://www.raspberrypi.org/forums/viewtopic.php?t=281095
 
  | terramex wrote:
  | RPI HQ camera is almost usable for astrophotography, here are
  | few shots I did with it last year:
  | https://terramex.neocities.org/astro/
  | 
  | Of course it make little sense from financial point of view as
  | good star tracker and optics are magnitudes more expensive but
  | it was fun.
  | 
  | I agree with rest of your post. Even MFT-size sensor would be
  | great as there are plenty great lenses with that image circle
  | size.
 
    | mnw21cam wrote:
    | I'm just comparing your Bode's Galaxy (f/3.3, 200mm, 120x21s)
    | with my recent attempt (f/6.3, 600mm, 42x30s), and besides
    | magnification, the result seems fairly similar - if anything,
    | I think the dark sections of your image are less noisy. Your
    | arrangement collected about 7.2 times as much light (ignoring
    | magnification), so that's not surprising. I was using a Nikon
    | D7500, so if the RPI HQ camera is comparing reasonably
    | favourably with that, then yes that's not bad.
 
    | dheera wrote:
    | Yeah it's barely usable, but not great, because ultimately
    | larger sensors will still give you better SNR for
    | astrophotography. A sensor with 10X the area will be able to
    | produce an image with the same final SNR in 1/10 the time.
    | 
    | Also I had lots of faint banding issues with RPi cameras.
    | Nobody was able to solve my problem on forums.
    | 
    | https://www.raspberrypi.org/forums/viewtopic.php?t=287866
 
      | terramex wrote:
      | I've seen similar banding in some tests when I had set
      | analog gain to 1.0 on a warm night. With analog gain set to
      | 16.0 and Peltier cooler attached to back of camera PCB it
      | was gone.
      | 
      | My guess is that IMX477 does some software de-noise that
      | causes banding. I tested this guess by calculating power
      | spectrum of a dark frame and there was noticeable drop in
      | higher frequencies. Unfortunately, even disabling hot-pixel
      | detection did not help. I did not investigate it further.
 
        | dheera wrote:
        | > Peltier cooler attached to back of camera PCB
        | 
        | Do you have plans or pics of how to do this? Especially
        | how to do it without getting condensation on the
        | electronics?
        | 
        | Thanks!
 
        | terramex wrote:
        | Honestly, it is just a frankenstein monster of whatever I
        | had on hand: https://imgur.com/a/QhvmbUa
        | 
        | 3mm thermal pad I used between PCB and cooler:
        | https://botland.store/thermoconductive-tapes-
        | pastes/6060-the...
        | 
        | Radiator (I used the smaller one that typically goes on
        | cold side of Peltier): https://botland.store/peltier-
        | elements/10024-heatsink-with-a...
        | 
        | Fan is standard 40mmx40mm, there is some generic copper
        | thermal paste between Peltier and radiator. The plywood
        | mount is DIY made with with hole drills. It is a bit too
        | thick so I used 2x C-CS mount adapters (like the one
        | bundled with the camera) to get more space, otherwise I
        | would not be able to screw in lens adapter.
        | 
        | There was a bit of neoprene foam between radiator and fan
        | to reduce vibrations but it looks like I lost it
        | somewhere.
        | 
        | About condensation: it was always wet or even icy in
        | operation but it never caused any electrical issues, I
        | guess condensed water was not very conductive? Once on a
        | cold night (about 5C) I had water condensation on the
        | sensor itself but it did not cause any lasting damage.
        | I've read that putting a fresh silica gel desiccant
        | packet into lens adapter helps. I had plans to attach
        | temperature probe to lens mount and control cooling power
        | form Pi itself, will get back to it in the future. The
        | camera sensor itself has embedded thermometer but it is
        | not exposed in camera driver.
 
  | PragmaticPulp wrote:
  | APS-C sensors are still significantly more expensive than
  | common sensors like the IMX477. Demand would be much lower due
  | to the high price for the sensor and additional cost for lenses
  | and mounting hardware.
  | 
  | RPi foundation isn't really targeted at the niche, high-end,
  | low-volume markets that demand the best of the best. They're
  | great at delivering an excellent compromise of cost and
  | quality. The IMX477 is just right for most use cases.
  | 
  | The sensor alone doesn't deliver 100% of the result of a modern
  | SLR. The image processing code does a lot of heavy lifting that
  | is mostly proprietary. The open source options are improving,
  | but connecting an APS-C sensor to an R-Pi wouldn't
  | automatically give you a DIY SLR competitor.
  | 
  | You'd spend a lot more in the process and get worse results
  | than just buying a commercial SLR camera and running open-
  | source scriptable firmware like Magic Lantern:
  | https://magiclantern.fm/
 
    | dheera wrote:
    | > Demand would be much lower
    | 
    | Lenses for full frame cameras are _super cheap_ -- you can
    | find tons of old Russian, Japanese, and East German lenses
    | that will work really well. Many of those lenses are built
    | like tanks and can be had for  <$100, some <$50. Most of them
    | produce _very nice_ images and aesthetically have much better
    | look than what I see out of these CCTV lenses for the Pi HQ
    | camera. CCTV lenses were never designed for art, and among
    | other things produce horrible out-of-focus highlights.
    | 
    | > The image processing code
    | 
    | Well yes, that's also the point, by having an open source
    | APS-C or full frame camera you can tinker to your heart's
    | content with changing the image processing code.
    | 
    | I use Magic Lantern extensively and there's only so much you
    | can do with it, and it's a pain in the ass to recompile code
    | for it. Having a full-fledged Linux system with gcc, opencv,
    | python, and pytorch at my disposal on camera, and with Wi-Fi,
    | Bluetooth, USB, and running an SSH server, and the ability to
    | connect arbitrary I2C and SPI sensors, would be freaking
    | amazing, to say the least.
    | 
    | Wildlife camera with thermal camera trigger and a neural net
    | that recognizes mountain lions? You got it.
    | 
    | LIDAR-based insanely accurate servo-driven autofocus? You got
    | it.
    | 
    | Microphone array that figures out who in the picture is
    | talking and refocuses the camera to that person? You got it.
    | 
    | Home-made Alt-Az tracker with built-in autoguider and remote
    | Wi-Fi progress monitoring? You got it.
    | 
    | And if it can be made to work with the Pi, someone will
    | hopefully also make it work with a Jetson Nano or Xavier NX
    | and then voila I could do some neural net processing in real-
    | time on-board. I've been able to blow Canon's in-camera
    | denoising out of the water with state-of-the-art neural nets
    | by postprocessing RAW images, and if I had a Xavier or Nano
    | on-board I could easily put those neural nets in-camera for
    | convenience.
    | 
    | The possibilities are endless, which is why I really want
    | this hardware so much.
 
      | PragmaticPulp wrote:
      | Everything you described can be built out with this
      | existing sensor and hardware.
      | 
      | You don't need an APS-C or larger sensor to get decent
      | images. Most APS-C sensors use a different high-speed
      | interface that won't work with the Raspberry Pi anyway.
      | 
      | Really, this solution from the Raspberry Pi foundation is a
      | great start for any of the projects you mentioned. It's
      | also cheap and highly available.
 
        | dheera wrote:
        | > You don't need an APS-C or larger sensor to get decent
        | images.
        | 
        | I don't have the space and time to debate the merits here
        | but there is a reason they exist, there are lots of
        | things you can get by having a large sensor (including a
        | different aesthetic and better SNR for low light images)
        | and I want those things with a hackable interface and
        | programmatic control of whatever the sensor is capable
        | of.
        | 
        | I've been doing photography with full frame sensors for a
        | a decade after upgrading from APS-C and telling me "you
        | don't need an APS-C camera" without understanding why I
        | use a full frame camera or the work I produce with them
        | isn't really helpful.
 
    | porphyra wrote:
    | APS-C sensors are maybe only a few hundred bucks.
    | 
    | I would love to have a nice APS-C or full frame board-level
    | camera that can be easily integrated into something like a
    | Raspberry Pi. At present it is nearly impossible to get
    | something like that --- dev kits for large sensors from Sony
    | Semicon, Canon, and ams are profoundly expensive, only sold
    | to companies, and go through a lengthy quoting process.
    | 
    | > The sensor alone doesn't deliver 100% of the result of a
    | modern SLR. The image processing code does a lot of heavy
    | lifting that is mostly proprietary.
    | 
    | This is HN, hackers like us love to be able to tinker with
    | the heavy lifting. That's the whole point of the Raspberry Pi
    | cameras. Even with the current HQ camera, a used point-and-
    | shoot camera with a similarly-sized sensor (or even bigger
    | sensor) would tend to produce better images and videos while
    | being more compact, robust, convenient, and cheaper than the
    | DIY camera.
 
      | dheera wrote:
      | > At present it is nearly impossible to get something like
      | that
      | 
      | So in the astrophotography world they exist. This for
      | example:
      | 
      | https://astronomy-imaging-camera.com/product/asi6200mc-
      | pro-c...
      | 
      | uses an IMX455 full frame sensor, gives you a reasonably
      | hackable full frame camera (not that well supported, but
      | there are grassroots libraries around) but it's $4000
      | because it's also a cooled camera.
      | 
      | If they had a version of it that's not cooled and just for
      | normal photography for $1000 that'd be awesome.
 
      | PragmaticPulp wrote:
      | > APS-C sensors are maybe only a few hundred bucks.
      | 
      | Where are you sourcing APS-C sized MIPI CSI sensors for a
      | few hundred bucks in low quantities?
      | 
      | Larger sensors tend to use SLVS-EC interfaces rather than
      | MIPI CSI used in the Raspberry Pi. The Raspberry Pi doesn't
      | even support full 4-lane MIPI-CSI (except on the CM4). It's
      | limited to 2-lane MIPI-CSI.
 
  | JKCalhoun wrote:
  | I agree, it would be nice, but is there no way for you or me to
  | construct such a thing using some existing chipset or module
  | and constructing an interface to the Raspberry Pi?
 
| ajsharp wrote:
| this is amazing :)
 
| mattowen_uk wrote:
| I toyed with this idea, as I find taking pictures with my phone
| to be an unsatisfactory experience, and carrying around my Canon
| EOS is annoying as it's too bulky.
| 
| What stopped me was: 1) Raspberry PI boot-up time. It's long
| enough to prevent you from quickly snapping a picture when you
| see it - you have to be prepared. 2) Battery power that doesn't
| run down within a couple of days of non-use.
 
  | bduhan wrote:
  | Boot times of 3-4 seconds are achievable with a customized
  | buildroot [1] [2] if you don't need network, USB, HDMI, and
  | other services.
  | 
  | [1] https://mitxela.com/projects/thermal_paper_polaroid
  | 
  | [2] https://himeshp.blogspot.com/2018/08/fast-boot-with-
  | raspberr...
 
| abdullahkhalids wrote:
| As a prof seeings students waste time scanning their homework,
| one gadget I want to build is a easy to use scanner, with a Rpi
| Zero and a cheap camera.
| 
| The idea is to have the camera with a wide angle lens attached to
| the top of stack of papers/notebook. Pressing a button takes a
| picture, and then does a affine transform (?) on it get the
| perspective right, then uploads it to the LMS.
| 
| Just a clean, hassle free experience. No orienting your phone
| awkwardly, no getting the lighting right, no mini edits on your
| phone, no compiling pdfs.
| 
| Also, very useful for me, as I like to do math by hand.
| 
| Edit: Image https://imgur.com/Fb45H7M.png The fact that camera is
| fixed relative to paper means the transform is also fixed. Multi-
| colored led (and knowledge of paper color) can also fix lighting.
 
  | akeck wrote:
  | Towards the end of my math degree, I started doing written
  | homework assignemnts in Inkscape using the pen tool and a Wacom
  | tablet. It worked surprisingly well.
 
  | hrktb wrote:
  | Phone scanners are already there.
  | 
  | Auto scanning with border and angle detection works decently
  | well [0], mini tripods with phone brackets abound. It's very
  | easy to set a phone above the table at a slight angle (that
  | makes it easier to move the docs in and out and get rid of
  | shadows) with the app auto scanning every sheet that's laid
  | below.
  | 
  | [0] I used Scanner Pro by Readle, on iOS for reference
 
    | abdullahkhalids wrote:
    | Funny how an Apple consumer is advocating for a "fiddly"
    | solution. I only use linux, but I was actually inspired by
    | the Apple philosophy in this. A one-button, no-nonsense
    | solution.
 
    | ska wrote:
    | They work ok, but are fiddly. I think OP is looking for
    | something more bulletproof with a better workflow.
    | 
    | Come to think of it a frame with a black base and an overhead
    | light incorporating a phone holder would likely do the trick
    | well.
 
      | abdullahkhalids wrote:
      | It will technically work. But do you think a student who
      | still wants to appear "cool" is going to whip out the
      | contraption you mention in front of their peers? There is
      | more to solutions to problems than the technological
      | possibilities.
 
        | ska wrote:
        | Sure, but that applies at least as much to the original
        | solution.
        | 
        | And this seems more of a 'on my desk at home' sort of
        | problem space than a 'whip it out of my bag' sort.
 
      | porknubbins wrote:
      | Having built a lot of rpi projects bulletproof is the last
      | word that comes to mind though. I mean the software end is
      | usually fine if the sd card doesn't get corrupted but
      | building physically robust devices is a serious challenge.
 
    | tga wrote:
    | Just in case someone didn't know this and finds it useful:
    | the system Files app on iOS can also scan documents to PDF,
    | including perspective correction. I believe the Notes app can
    | do that too.
 
      | spaceisballer wrote:
      | The notes app can definitely do this and works quite well.
      | It's never worth the trouble of taking out my scanner
      | anymore. If you have decent lighting and a contrasting
      | background for the document it almost never requires
      | refining for me.
 
  | LegitShady wrote:
  | I have thousands of photos of homework from when I was in
  | school stored in Google photos. I always took pictures as a
  | backup but the stuff I submitted I always scanned using a real
  | scanner because it was hard to get a perfectly parallel photo
  | with good lighting.
 
  | enchiridion wrote:
  | I believe it would a homography transform, which is less
  | constrained than an affine transform, as it does not preserve
  | parallel lines/angles. Instead it maps lines to lines as a way
  | to adjust perspective.
  | 
  | https://en.wikipedia.org/wiki/Homography
 
  | vanderZwan wrote:
  | Open Note Scanner does this quite well on Android, in my
  | experience.
  | 
  | https://github.com/allgood/OpenNoteScanner
  | 
  | https://f-droid.org/en/packages/com.todobom.opennotescanner/
  | 
  | https://play.google.com/store/apps/details?id=com.todobom.op...
 
    | abdullahkhalids wrote:
    | Yes, phone apps work, but they still require several clicks
    | to get things right, and upload. But if your camera is fixed
    | relative to the paper, then there is a single known transform
    | that will correct perspective. If you write software to
    | integrate directly with the LMS, then it will only require
    | one hardware button press per page, to upload the assignment.
 
      | ska wrote:
      | Really the transform isn't as much trouble as getting a
      | uniformly lit area with good contrast.
 
        | abdullahkhalids wrote:
        | Yes, that could be problematic, hence I incorporated the
        | LED in my proposal image.
        | 
        | As we are working with standard paper, we know its color
        | (as it appears to the camera in neutral light). We could
        | have a calibration step, where the multicolored LEDs are
        | tuned to get the right contrast and color balance.
        | Though, I have no idea how well it will work in practice.
 
        | [deleted]
 
      | jjeaff wrote:
      | Seems like to get it to work at such a sharp angle, you
      | would need a very large depth of field with your lense in
      | order to keep both the nearest and farthest portions of the
      | page in focus.
 
        | abdullahkhalids wrote:
        | I do have a phd in a theoretical quantum optics, so no, I
        | have no idea if such a weird angle will actually work in
        | practice given the physical and budgetary constraints.
        | :-D
        | 
        | Seriously, though, I have idea. We can take two pictures
        | focusing once the near part, and once on the far part.
        | 
        | If cameras are cheap (I haven't researched), maybe two on
        | either end of the device would mitigate the complexity of
        | the lenses required.
 
  | spoonjim wrote:
  | Might be useful in a place where no one has smartphones but
  | otherwise why not use the smartphone camera that people already
  | have?
 
  | tootie wrote:
  | I do scanning to PDF just with Google Drive on my phone. You
  | can also buy (or DIY) a scanning box like this guy:
  | https://smile.amazon.com/Scanner-Bin-Document-Scanning-Solut...
  | 
  | I've seen models that also have LED strips for even lighting.
  | What I haven't seen is a gadget that can feed multiple sheets
  | easily.
 
  | jimbob45 wrote:
  | Do you not accept phone pictures of homework? That's what I
  | used to submit and the clarity was enough for TAs to be able to
  | readily spot mistakes.
 
    | abdullahkhalids wrote:
    | Of course I do. But students are probably taking like 50
    | pictures a week for their various courses. I don't think they
    | like the tediousness of it.
    | 
    | Plus with this, I could look at student solutions much easier
    | during class or office hours.
    | 
    | Similarly, I don't want to whip out my phone to take 30
    | pictures of my research notes one by one.
 
  | brudgers wrote:
  | A module on making pictures with the phone would have fewer
  | dependencies. Most of the problem is simply not understanding
  | the problem space. Humans have had less than two hundred years
  | dealing with it and only a decade or so since everyone had a
  | camera in their pocket all the time and about a year of
  | scanning photographs for academia.
 
  | JKCalhoun wrote:
  | Notes that ships with iOS actually has a nice document scanner
  | built in that uses the phone camera ... I mean it does the
  | transform you describe to get better-than-normal document
  | photos.
  | 
  | Too bad it then simply adds as an attachment to the note and
  | doesn't allow you to go straight to Share.
 
    | brundolf wrote:
    | There are other apps that do similar things. When I was in
    | college a decade ago I was using "CamScanner", which seems to
    | still be around (though I feel like I read recently that it
    | got bought and the new owners started doing something
    | sketchy)
    | 
    | These days I just use the regular camera app. Documents are
    | plenty readable as-is, and you can straighten/adjust 3D
    | perspective/raise contrast using the regular photo editing
    | features (at least in iOS)
 
  | mlyle wrote:
  | Clearscanner on the phone does this -- my kids use it for their
  | homework. Snaps pictures, finds edges, does affine transform,
  | corrects exposure, and assembles into PDF.
 
    | sneak wrote:
    | I went into the app store to see about this app, having not
    | heard about it yet. The app's privacy policy says it uses
    | Firebase (Google) Analytics, which transmits information
    | about your use of the app off the device without consent.
    | 
    | This, to me, means I can never trust it for scanning
    | sensitive or private documents, because who knows what it's
    | sending. I declined to install it. YMMV.
 
      | mlyle wrote:
      | This is in the context of scanning homework assignments.
      | 
      | Not to mention-- Firebase tracks what, events? You think
      | somehow it's encoding the documents in an event stream to
      | exfiltrate them?
 
        | sneak wrote:
        | An app that shares my event data silently and without
        | consent cannot be trusted with even low-grade private
        | information. Why would I ever allow it on a device that
        | handles high-grade private information?
 
        | mlyle wrote:
        | > An app that shares my event data silently and without
        | consent
        | 
        | You're complaining about a -disclosed- use of analytics.
        | 
        | It seems like you'd be happier with an app that just
        | didn't mention the use.
 
        | jjeaff wrote:
        | It's not without consent nor is it silently. You consent
        | when you decide to install it and it's not silently if
        | they just told you that it happens.
 
      | StavrosK wrote:
      | Can you not just block its internet connection?
 
        | sneak wrote:
        | Not conveniently on iOS.
 
        | StavrosK wrote:
        | Ah, that's unfortunate.
 
      | snthd wrote:
      | You might like OpenNoteScanner
      | https://github.com/allgood/OpenNoteScanner
 
| yoloswagins wrote:
| I would love to see a guide to fitting an rpi camera module into
| a film camera back, to bring old film cameras into the modern
| age.
 
  | CloselyChunky wrote:
  | During the quarantine, I started photographing on film,
  | developing the film at home and digitize the negatives using my
  | DSLR. At least for B/W film, the process of developing film
  | yourself is dead easy and I'm happy to have a hobby away from
  | my computer. Also, having a price per picture and only a
  | limited amount of shots helps me actually think about composing
  | nice pictures instead of taking 5 almost identical images and
  | moving on.
  | 
  | In general, film photography is having a comeback. Prices for
  | used film cameras skyrocketed in the last years for a few
  | models.
  | 
  | Personally, I find photographing on film really rewarding.
  | Having a physical product in the end (be it a print of the
  | image or only the negatives) makes the process more enjoyable.
  | So if you have some old film cameras lying around, I can only
  | recommend giving them a try. Maybe there are even old films
  | with old memories in these cameras.
 
  | fish_phrenology wrote:
  | I was thinking about this yesterday while looking for resources
  | on building a board to read data from a modern sensor from
  | something like an a7 (turns out its way over my head). The
  | issue you'd run into with the pi hq camera module assuming you
  | can get the focal plane right and everything to fit is that the
  | sensor is way smaller than 35 film so you'll have a rather
  | large crop factor.
 
  | brudgers wrote:
  | The issue is the difference in "sensor" size. The "crop factor"
  | of the rPi camera is 5.5 so a 50mm lens provides an angle of
  | view equivalent to a 275mm lens for 35mm film.
  | 
  | To get down into "normal" lens equivalent would require
  | something like 8mm. A fisheye would probably be ok because the
  | center tends to be relatively less distorted. But if there are
  | 8mm rectilinear lenses for 35mm film cameras you probably can't
  | find one and maybe not afford one...Its price would buy a lot
  | of film.
  | 
  | I mean there are digital sensors that retrofit film cameras.
  | Products for Hasselblad 500 series and Mamiya RB have been
  | around since the early days of digital. They have always been
  | less than $100k and still are today.
  | 
  | Anyway if you want to use an old film camera, just buy some
  | film and have a go. They are incredible mechanical devices and
  | a pleasure in the hand and produce that film look naturally.
 
  | throwanem wrote:
  | It would have to vary pretty heavily by film camera model, and
  | many probably can't be nondestructively modified that way.
  | Nikon F and whatever Canon's film flagships were, sure - those
  | are designed to take a motor drive winder, so you can remove
  | the back cover entirely. But my heirloom Nikkormat FTn, for
  | example, wasn't designed that way, and removing the film cover
  | hinge pin would at best be a very fiddly task with a
  | significant risk of damaging the hinge.
  | 
  | That said, and assuming you use a camera module that you can
  | disassemble far enough to expose the sensor, it shouldn't be
  | too hard. You'd most easily I think design and 3D-print a
  | replacement cover with a light-tight fitting to place the
  | sensor on center at the flange focal distance (ie in the
  | designed film plane), and route whatever cables out to where
  | you could connect them. Maybe also a case for the Pi that has a
  | 1/4"-20 screw to mount on the tripod socket, just so you don't
  | have to cram your face past it to get a good look down the
  | viewfinder.
  | 
  | You'd probably have a hard time getting anything like a wide-
  | angle shot. I don't know offhand what sensor sizes are common
  | in RPi camera modules, but I feel like expecting 1"-class would
  | be expecting too much, so you'd be dealing with a pretty fierce
  | crop factor.
 
  | dheera wrote:
  | I use film camera lenses all the time on my full-frame consumer
  | digital camera, which is at present a slightly better way to
  | bring 35mm film camera _lenses_ back into the modern age.
  | 
  | The problem with retrofitting a film camera back with a Pi
  | camera is that the Pi camera has a dinky little IMX477 sensor
  | which only covers a small, small fraction of the area that
  | would normally be illuminated on 35mm film, so you would not
  | get very good images at all.
  | 
  | If they came out with a full-frame sensor that plugged into the
  | Pi though, that would be _awesome_.
  | 
  | That said -- that's for 35mm cameras. Now there are also other
  | film cameras ... I am working on using a Pi camera to scan a
  | _large format_ 4x5 area to bring a Toyo view camera back into
  | the modern age :). It takes a good 15-20 minutes to scan the
  | image and I get gigapixel results. Still a work in progress.
  | Un-doing the effect of CRA optimization on the sensor 's
  | microlens array is annoying.
  | 
  | https://www.instagram.com/dheeranet.large/
 
    | JKCalhoun wrote:
    | Cool. I remember when flatbed scanners were pressed into
    | service to make (very) large format images.
    | 
    | Stephen Johnson was playing around with this in the 1990's.
    | 
    | http://www.betterlight.com/field_photography.html
    | 
    | "I initially captured 180 degrees of view in a 6,000 x 40,055
    | pixel image, but soon learned that Photoshop was limited to
    | opening files with less than 30,000 pixels in either
    | dimension, so I had to perform surgery on the original TIFF
    | file to reduce the image to just under this limit."
 
      | dheera wrote:
      | I thought about that method as well and after taking apart
      | about 3 scanners it stopped being fun. Scanner assemblies
      | are _really_ hard to work with. Especially that some of
      | them strobe colored RGB lights instead of a colored sensor,
      | some use microlenses, and some won 't start scanning if
      | they detect that the light has failed (and you don't want
      | the light for photography, so you disconnect the lights but
      | then find that it refuses to scan). However if there's a
      | hackable linear color CCD that is 4 inches long that I can
      | wire into a RPi that might be super interesting.
 
    | fish_phrenology wrote:
    | Now that is a neat idea. I was thinking about making a film
    | scanner that can auto scan + cut rolls of 120 and 35 but this
    | is way neater. Thank you for sharing!
 
| jrussino wrote:
| Is there a solid open-source Rpi-based home security camera
| solution yet? I'd like to set up something of comparable quality
| to say a Ring doorbell camera or a Nest/Blink security cam or a
| baby monitor but that I can fully control.
 
  | varispeed wrote:
  | I've been thinking about just getting off the shelf system like
  | Hivision IP camera and NVR, then run it on a separate network
  | disconnected from internet. It shouldn't be much more
  | expensive, but still I'd probably disassemble cameras to make
  | sure there is no wifi of other means to leak data.
 
  | markfchapman wrote:
  | I'm thinking of looking at this...
  | 
  | https://github.com/ccrisan/motioneyeos
  | 
  | ...has anyone used it?
 
  | jjeaff wrote:
  | Not rpi, but I think there seems to be a pretty solid system
  | built up around the esp32-cam devices using esphome, which are
  | actually quite a bit cheaper and lower power than rpi.
  | 
  | https://home-assistant-guide.com/2020/10/08/building-a-video...
 
  | buran77 wrote:
  | Have you looked at motionEyeOS? I'm not sure how it compares to
  | Nest/Blink but I got along very well with it since 2015
  | (originally as motionPie).
  | 
  | https://github.com/ccrisan/motioneyeos
 
  | cvwright wrote:
  | That's been a dream of mine for a long time. I don't think
  | there's anything quite like we want just yet.
  | 
  | However, there is a super cool open source project from the
  | author of GKrellM (remember that from the ancient days of
  | Linux?). He's using the Pi's built-in hardware video coder to
  | get high quality motion detection very cheaply. The basic idea
  | seems to be, when the encoder produced a lot of bits, there
  | must have been some motion in the frame.
  | 
  | https://github.com/billw2/pikrellcam
 
  | tonmoy wrote:
  | I set up a reolink PoE camera with a PoE injector connected
  | directory to a RPi. The RPi itself is connected to the Wifi and
  | I have homeassistant running on it and the camera itself can
  | generate an event when it detects a motion that homeassistant
  | can do stuff with. I am pretty happy with this solution.
 
  | paxswill wrote:
  | I briefly used Kerberos.io a few years ago (kind of a difficult
  | name SEO-wise), and it seemed to work pretty well.
 
| rubatuga wrote:
| Just buy a used Lumix GF2
 
| augbot wrote:
| There are c-mount to Canon EOS lens adapters. Could take this
| project to the next level!
 
  | graiz wrote:
  | I tried this with little success. The c-mount is such a cropped
  | sensor that even with the EOS lens adapter you only get the
  | middle of the shot... also I haven't found a good solution for
  | focus and f-stop that is buried inside the EOS pin protocol.
  | I'm sure it's solvable but haven't found it yet.
 
| daveslash wrote:
| This may be a dumb question, but I haven't borked around with the
| Pi Camera at all yet.... Why does the lens have a megapixel
| rating? I'd assume that there's no imaging sensor in it, right?
 
  | [deleted]
 
  | PragmaticPulp wrote:
  | > Why does the lens have a megapixel rating? I'd assume that
  | there's no imaging sensor in it, right?
  | 
  | The megapixel rating is an indicator for sharpness. There are
  | more technical ways to rate sharpness, but listing the
  | megapixel rating and sensor size is a quick way to suggest that
  | the lens is sharp enough to resolve pixels that small.
 
  | throwanem wrote:
  | It doesn't make sense, no. The whole article seems very
  | barebones - I'd have expected to see discussion of how the
  | sensor-lens system needs to work for proper focus, at least.
  | Granted they link the STL for their case, which will be
  | designed for correct alignment, but some discussion would still
  | be useful to those wanting to mod for different lenses or
  | sensors.
 
  | dheera wrote:
  | The lens having an MP rating is likely just saying that the
  | optics is good enough to resolve an image to the detail that a
  | 10MP sensor would capture.
  | 
  | I know it's a shitty way to specify lens resolution, but that's
  | likely what the manufacturer called it, not the fault of the
  | article's author.
 
    | daveslash wrote:
    | Thank you. That makes sense. Yes - that's the description
    | from the manufacturer, not the post author. Lens may be found
    | here. https://www.adafruit.com/product/4562
 
  | brudgers wrote:
  | The rPi camera accepts c-mount lenses. C-mount is a mechanic
  | standard for the connecting threaded couple of lens and camera.
  | 
  | It is not an optical standard.
  | 
  | C-mount lenses project image circles of different sizes
  | depending on their intended use. The initial use was 8mm film
  | cameras. But it was also used by lenses designed to cover the
  | larger super8 film image standard. And today there is at least
  | one c-mount lens that can nominally cover APS-C though with
  | noticeable vignette...anyway...
  | 
  | The rPi camera sensor has a diagonal of 7.9mm. This is about
  | 20% larger area than super8 film.
  | 
  | For a photographer whose opinions of image quality revolve
  | around technical details, such a super8 format intended lens
  | might produce about 10 "acceptable" megapixels on a 12mp
  | sensor.
  | 
  | Most photographers tend to think about image quality in those
  | terms. Limiting the specifications that way heads off
  | complaints about unfulfilled expectations. It is easier to hold
  | strong opinions about technical measures than to consider
  | aesthetic possibility created by a lens' optical limitations.
 
  | playpause wrote:
  | Good question. It looks like the Raspberry Pi HQ camera module
  | (the bit with the sensor) is rated at 12MP. My guess is that
  | the angle of this lens means you can only make use of the
  | middle portion of the sensor, in this case 10MP's worth of it.
  | And as there's only one sensor module on the market that this
  | lens can screw onto, they can tell you the effective megapixel
  | rating of the lens. There's also a 'wide angle' 6mm lens [1]
  | available for the same camera module, rated at 3MP, which I
  | assume casts the image on a even smaller portion of the sensor.
  | I could be completely wrong though, not an expert.
  | 
  | [1] https://thepihut.com/products/raspberry-pi-high-quality-
  | came...
 
    | JKCalhoun wrote:
    | I don't think you are correct. For this reason only: I have
    | played with the Raspberry Pi HQ camera module and a pair of
    | lenses for it and the frame-grab software never returned an
    | image with a black (or otherwise) border. From your
    | description I would instead expect a thick black border
    | around the image where no photon data was captured.
    | 
    | To be sure the frame-grab tool could be sensing the lightless
    | border from the image and cropping, but I doubt it's that
    | clever.
 
      | brudgers wrote:
      | Your description of the frame grab software output is
      | consistent with the proposed degree of cleverness.
 
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