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2bit Astrophotography with the Game Boy Camera

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Re: 2bit Astrophotography with the Game Boy Camera

#31

Post by keithpeter »

anfractuosity wrote: post #18
keithpeter wrote: post #16

Earlier quoted context omitted.

And noise? I used to do long exposure photos of interiors of buildings on film (~2h) but digital cameras seem challenged to me.

That's very interesting re. film. I'd be curious why that is. I've only ever done exposures less up to around a couple of minutes with film & digital. Do you have any examples that you shot for 2hr out of curiosity. Was that with ISO 50 or less, or did you use a darkening filter too? Edit: I wonder if it is due to reciprocity failure with film - https://en.wikipedia.org/wiki/Reciprocity_(photography) ?

125 asa FP4 roll film (all monochrome and hand developed needless to say, I used a Rollieflex camera on a tripod when I was playing with this stuff decades ago).

I found the correction chart below on t'web [1] just now.

I recollect using 2.5x per stop over 1 second which gives slightly longer exposures than [1], but then I did tend to 'pull' the development a bit (contrast goes up), so a 2 minute metered exposure would be 2.5^7 seconds (10 minutes) instead of 2^7 seconds roughly. A 10 minute exposure on the meter corresponds to two hours and a very significant contrast hike - I recollect printing on grade 1 and grade half filter settings (multigrade paper). I only used extreme exposure times in old dark interiors e.g. churches in the UK in November or something. Inside so no need for any filters - not astro.

I'll dig a few prints out and scan them over the weekend. Nowt astounding. See if you can find a book about Edwin Smith if you are near a library with a very good photography collection.

I have a fantasy of using 10x8 film with a pinhole camera and just doing contact prints... but then I remember the darkroom days and the amount of water that got used up...

[1] http://home.earthlink.net/~kitathome/LunarLight/moonlight_ga...

Re: 2bit Astrophotography with the Game Boy Camera

#32

Post by roywiggins »

Extigy wrote: post #27
makmanalp wrote: post #25

In case anyone here knows - where can one buy an "old-school" low-res / monochrome / dithered camera module that produces images this one, for easy use with a raspberry pi or arduino or something? All I get is weird electronics company websites with "request more info" buttons - nothing that gives me pricing and a "buy" button. Or alternatively, what's a way to transform high-res images to look like that?

There's an iOS app called Retrospecs that has some cool lo-fi filters.

8Bit Photo Lab on Android is pretty good.

Re: 2bit Astrophotography with the Game Boy Camera

#33

Post by anfractuosity »

joshvm wrote: post #30
makmanalp wrote: post #25

In case anyone here knows - where can one buy an "old-school" low-res / monochrome / dithered camera module that produces images this one, for easy use with a raspberry pi or arduino or something? All I get is weird electronics company websites with "request more info" buttons - nothing that gives me pricing and a "buy" button. Or alternatively, what's a way to transform high-res images to look like that?

Bin the image from a raspberry pi camera by a factor of.. 8 or so (maybe 16 if you need smaller)? Load the image as grayscale and divide the counts by 64 to get 2-bit values. Kinda difficult to buy crappy low resolution detectors these days because nobody makes them and you'd need to build the readout electronics yourself. You might as well just use a decent detector and make it look bad.

You can also interestingly get the raw sensor data from the Pi camera too, as in before the demosaicing is applied.

I wonder, this may be silly, but could you not potentially get a slightly higher resolution image, if you just created a pixel for every sensel. Than if you were to apply the demosaicing algorithm then convert to grayscale.

Re: 2bit Astrophotography with the Game Boy Camera

#34

Post by anfractuosity »

keithpeter wrote: post #31
anfractuosity wrote: post #18

Earlier quoted context omitted.

That's very interesting re. film. I'd be curious why that is. I've only ever done exposures less up to around a couple of minutes with film & digital. Do you have any examples that you shot for 2hr out of curiosity. Was that with ISO 50 or less, or did you use a darkening filter too? Edit: I wonder if it is due to reciprocity failure with film - https://en.wikipedia.org/wiki/Reciprocity_(photography) ?

125 asa FP4 roll film (all monochrome and hand developed needless to say, I used a Rollieflex camera on a tripod when I was playing with this stuff decades ago). I found the correction chart below on t'web [1] just now. I recollect using 2.5x per stop over 1 second which gives slightly longer exposures than [1], but then I did tend to 'pull' the development a bit (contrast goes up), so a 2 minute metered exposure wou…

That chart looks very interesting, thanks!

Cheers, I'd be very curious to see your prints.

I've just had a little look on google images at some of Edwin Smith's photos, they look stunning! The light in the photos look amazing.

I still have an old Pentax K1000 film camera I think it is, I'll have to dig it out again some time :) I'd really like to get a medium format camera, but they're still not super cheap, I was looking at the Mamiya RZ67 (I'd actually like to try shooting landscape with it, which could be impractical due to the weight, but would be fun nonetheless ;).

10x8 film would be awesome to play with!

Re: 2bit Astrophotography with the Game Boy Camera

#35

Post by joshu »

makmanalp wrote: post #25

In case anyone here knows - where can one buy an "old-school" low-res / monochrome / dithered camera module that produces images this one, for easy use with a raspberry pi or arduino or something? All I get is weird electronics company websites with "request more info" buttons - nothing that gives me pricing and a "buy" button. Or alternatively, what's a way to transform high-res images to look like that?

Use a normal camera and post-process. Use Imagemagick[1]

Like so: http://imgur.com/a/YpHzZ

http://www.imagemagick.org/Usage/quantize/

Re: 2bit Astrophotography with the Game Boy Camera

#36

Post by anfractuosity »

orbital-decay wrote: post #23
anfractuosity wrote: post #14

Earlier quoted context omitted.

Could you explain in laymans terms how that would work? If you're only obtaining a single value for a single pixel and there's no movement, how does the pixel value change even if there's a grating in front? Or do you mean the grating can still move?

The pattern still needs to be different at each sampling, yes. Moving the grating is one way to do it, or it can be done with a micromirror array, for example.

Gotcha cheers! A while ago I saw a single mirror MEMS device, could be useful for something like this, I believe you could control the horizontal/vertical angle.

Re: 2bit Astrophotography with the Game Boy Camera

#37

Post by colejohnson66 »

anfractuosity wrote: post #33
joshvm wrote: post #30

Earlier quoted context omitted.

Bin the image from a raspberry pi camera by a factor of.. 8 or so (maybe 16 if you need smaller)? Load the image as grayscale and divide the counts by 64 to get 2-bit values. Kinda difficult to buy crappy low resolution detectors these days because nobody makes them and you'd need to build the readout electronics yourself. You might as well just use a decent detector and make it look bad.

You can also interestingly get the raw sensor data from the Pi camera too, as in before the demosaicing is applied. I wonder, this may be silly, but could you not potentially get a slightly higher resolution image, if you just created a pixel for every sensel. Than if you were to apply the demosaicing algorithm then convert to grayscale.

Don’t older cameras have a higher SNR? How would you simulate that? Lower the bit depth?

Re: 2bit Astrophotography with the Game Boy Camera

#39

Post by joshumax »

objclxt wrote: post #9
Luc wrote: post #8

Earlier quoted context omitted.

The camera outputs analog values. I don't know for sure but I bet the dithering is applied right after the analog pixel is converted to digital...

Yep, here's the technical data sheet for the chip: https://people.ece.cornell.edu/land/courses/ece4760/FinalPro...

Looks like the maximum supported exposure time is ~1 second... That mixed with the fact that the fact that it has a fairly shallow well depth probably means that the CMOS would be best suited for LUCKY imaging. Also adding a cooler to the back of the Gameboy camera may help reduce amp glow. Anyone have the specs on the ADC chip?

Re: 2bit Astrophotography with the Game Boy Camera

#40

Post by serf »

app4soft wrote: post #17

CASIO WQV-1 is would be much better choice for 2-bit astrophotography.[1] [0] ftp://ftp.casio.co.jp/pub/watch/wc/WQVLink_Manual_K.pdf [1] http://www.3wheelers.com/elvis/body_wqv-1.html

digital camera watch from the early 2000's : 6 months of battery life on a CR2032 coin battery.

Current day smart watch (without a camera in most cases) : 24 hours to 1 week battery life using a lithium ion battery.

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