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by rkinch
Fri Jun 14, 2013 8:45 am
Forum: Camera board
Topic: M12 lens adapter for camera module
Replies: 80
Views: 80282

Re: M12 lens adapter for camera module

htbwmedia wrote:Seeing the name M12 caught my attention ...
I suspect you've confused the M12x0.5 threaded lenses we're discussing here with something else in your trade called "M12" that is unrelated.
by rkinch
Fri Jun 14, 2013 6:10 am
Forum: Camera board
Topic: M12 lens adapter for camera module
Replies: 80
Views: 80282

Re: M12 lens adapter for camera module

Here's a $6 (delivered!) solid cast zinc M12 board camera case I received from China today: _.jpg The Raspicam almost fits directly (if you moved the sticky-mount for the chip to center it on the board it would fit) or you could hacksaw/file/drill it to make a metal M12 receptacle you mount with scr...
by rkinch
Fri Jun 14, 2013 3:06 am
Forum: Camera board
Topic: RAW output information
Replies: 236
Views: 97896

Re: RAW output information

towolf wrote:But fall-off on a 35mm full frame lens is probably insignificant when you are using a sensor with a crop factor of around 10.
No, the cos4 falloff depends on the FOV angle which is a function only of focal length and sensor size, and independent of the lens format (SLR, C/CS-mount, M12, etc.).
by rkinch
Fri Jun 14, 2013 2:55 am
Forum: Camera board
Topic: M12 lens adapter for camera module
Replies: 80
Views: 80282

Re: M12 lens adapter for camera module

Nicely improvised, but why risk the destructive disassembly of the housing? All you need is to unscrew the lens. The M12 receptacle fits over the stock lens receptable. And this retains the IR filter, which you need.
by rkinch
Thu Jun 13, 2013 9:47 pm
Forum: Camera board
Topic: RAW output information
Replies: 236
Views: 97896

Re: RAW output information

DSLR lenses are large enough, for example, that no lens shading correction is required ... Eh? DSLR optics have this aplenty. The Canon 5D Mark III features lens correction in the firmware, both shading and lateral color. And Canon has provided it in their DSLR RAW post-processing software for years.
by rkinch
Thu Jun 13, 2013 9:31 pm
Forum: Camera board
Topic: M12 lens adapter for camera module
Replies: 80
Views: 80282

Re: M12 lens adapter for camera module

Could one re-position the plastic camera onto a plate that has holes for the new housing? Several things about this prospective improvisation worth noting: (1) The M12 inside thread minor diameter minimum is (happy accident!) just barely larger than the diagonal of the 8mm-sided square stock lens h...
by rkinch
Thu Jun 13, 2013 5:03 am
Forum: Camera board
Topic: M12 lens adapter for camera module
Replies: 80
Views: 80282

Re: M12 lens adapter for camera module

Is there any chance you'll be selling the board and attachment pre-assembled? Yes, I can sell assemblies with a new camera module. For the moment I only have two extra camera modules on hand, and I hear they're not going to be available for another month or more. The riskiest part of the installati...
by rkinch
Thu Jun 13, 2013 3:46 am
Forum: Other projects
Topic: Proto Armour for Raspberry Pi Now Available!
Replies: 13
Views: 7272

Re: Proto Armour for Raspberry Pi Now Available!

What's the milling center?

You fixture 4 at a time? And don't you have to flip it to machine the bottom? Or how do you make the blanks?
by rkinch
Thu Jun 13, 2013 3:07 am
Forum: For sale
Topic: Proto Armour for Raspberry Pi and Camera Available
Replies: 14
Views: 7562

Re: Proto Armour Rock Solid Protection

This is a beautifully designed and machined solid aluminum case. Very reasonably priced for this type of work. I would recommend it for rugged applications, or where you need to modify the case to fit to other things. The only problem I found was that the opening for the USB Micro-B power connector ...
by rkinch
Wed Jun 12, 2013 9:12 pm
Forum: Camera board
Topic: M12 lens adapter for camera module
Replies: 80
Views: 80282

Re: M12 lens adapter for camera module

Please order samples here:

http://www.truetex.com/order-rp12.htm
by rkinch
Wed Jun 12, 2013 6:38 am
Forum: Camera board
Topic: first use in spectroscope?
Replies: 17
Views: 8062

Re: first use in spectroscope?

So the R-Pi camera can see this near-IR wavelength, but certainly a lot more dimly than the security camera. OK, this is about what should have been expected. The IR filter attenuates, but not completely. The IR remote for my HDTV display looks very bright in the Raspicam. Perhaps it is 730 nm rath...
by rkinch
Tue Jun 11, 2013 11:36 pm
Forum: Camera board
Topic: first use in spectroscope?
Replies: 17
Views: 8062

Re: first use in spectroscope?

I think the apparent falloff in image pixel values at 680 nm on the spectroscope output can only be due to the IR filter. I would tend to agree, but did you take my suggestion to look at an IR remote with the camera module? What do you see then? Could there be elements in the spectroscope which mig...
by rkinch
Tue Jun 11, 2013 11:32 pm
Forum: Camera board
Topic: first use in spectroscope?
Replies: 17
Views: 8062

Re: first use in spectroscope?

... there's obviously some very heavy processing going on to counter the flaws of the stock lens. What heavy processing? There may be an application of the LENC correction feature built into the OV5647, which is just a simple light falloff correction, but this is not anything to do with lens aberra...
by rkinch
Tue Jun 11, 2013 7:38 pm
Forum: Camera board
Topic: first use in spectroscope?
Replies: 17
Views: 8062

Re: first use in spectroscope?

I'm curious if you found the default built-in sharpening to remain reasonable with the replacement lenses, or did it seem to be too much or too little. The lens quality issue is primarily a matter of the MTF of the lens being applied. I assume MTF is not even published for the stock Raspicam "myste...
by rkinch
Tue Jun 11, 2013 7:21 am
Forum: Camera board
Topic: Camera Interface Specs
Replies: 353
Views: 89598

Re: Camera Interface Specs

That's only really possible with HDMI in. But HDMI-in itself is not possible. That's why there are never HDMI inputs on video recorders. Of course it's possible (I've seen it done). I think its Toshiba who do a HDMI to CSI convertor chip which would be easier to do than the scheme I have seen. I su...
by rkinch
Tue Jun 11, 2013 6:24 am
Forum: Camera board
Topic: Camera Interface Specs
Replies: 353
Views: 89598

Re: Camera Interface Specs

jamesh wrote:That's only really possible with HDMI in.
But HDMI-in itself is not possible. That's why there are never HDMI inputs on video recorders.
by rkinch
Tue Jun 11, 2013 3:29 am
Forum: Camera board
Topic: first use in spectroscope?
Replies: 17
Views: 8062

Re: first use in spectroscope?

I'm looking forward to hearing how you get on with other lenses. It seems simple enough in concept, but I think no one has yet reported a working camera with a non-stock lens. I've successfully tried various M12 lenses from 2.8 to 35 mm on the Raspicam. There's a M12 50mm on the market but I don't ...
by rkinch
Tue Jun 11, 2013 2:59 am
Forum: Camera board
Topic: first use in spectroscope?
Replies: 17
Views: 8062

Re: first use in spectroscope?

jbeale wrote:By the way, if you want to spend $100 to get a smaller field of view, you can get a 2x extender lens ...
Better to just replace the lens with one in the appropriate focal length. Hence my M12 lens adapter: http://www.raspberrypi.org/phpBB3/viewtopic.php?t=45887
by rkinch
Mon Jun 10, 2013 7:05 pm
Forum: Camera board
Topic: first use in spectroscope?
Replies: 17
Views: 8062

Re: first use in spectroscope?

It has no refractive optics anywhere! The "eyepiece" is in fact a simple aperture with a naked transmission grating immediately on the other side. Right, I guess have an even cheaper plastic version of this on my shelf, no eyepiece. It's a "bring your own eyepiece" device: requires pre-pubescent ac...
by rkinch
Mon Jun 10, 2013 11:28 am
Forum: Camera board
Topic: first use in spectroscope?
Replies: 17
Views: 8062

Re: first use in spectroscope?

Nice. The Raspberry Pi camera module can image through the eyepiece of any instrument in general, because its lens has a shallower and smaller entrance pupil than the human eye. Microscopes, telescopes, endoscopes, .... The only limitation is that the field of view presented by the instrument may be...
by rkinch
Mon Jun 10, 2013 6:53 am
Forum: Camera board
Topic: setting lens focus
Replies: 27
Views: 52019

Re: setting lens focus

jbeale wrote:I'm not sure if I could detect 40 microns of motion.
That's a minimum. You'll see it go in and out of focus if you touch the lens. Elastomeric glue blobs might be acting as a preload spring.
by rkinch
Mon Jun 10, 2013 5:40 am
Forum: Camera board
Topic: setting lens focus
Replies: 27
Views: 52019

Re: setting lens focus

Since this simple thread fit is not purposed for precision focus adjustment, some understanding and improvisation is needed to make it work well as such. I measure the stock lens as having a metric thread, namely M6x0.35. So a fraction of a turn is only a few tenths of a mm at most. There is a lot o...
by rkinch
Sun Jun 09, 2013 10:10 am
Forum: Camera board
Topic: Camera info - a set of questions
Replies: 10
Views: 1870

Re: Camera info - a set of questions

Can you give the concern trolling a bit of a rest? Quite a few of your posts have made sideswipes at the fact the GPU is closed source. We know this. The OP *didn't* know this, that's why he asked. I answered. Nobody means to be fishing or trolling or sideswiping. Please ignore any provocations fro...
by rkinch
Sat Jun 08, 2013 7:00 pm
Forum: Camera board
Topic: Camera info - a set of questions
Replies: 10
Views: 1870

Re: Camera info - a set of questions

Decent questions, but the answers are inside a proprietary box, as you say, "magic." Not the sort of thing the few people who know are eager to spend time answering, if you reference my pleading for a flash sync feature. The good people who made this thing meant it for educational missions, by which...

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