dan3008 wrote:Pays your money, takes your choice
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.dan3008 wrote:Is there any chance you'll be selling the board and attachment pre-assembled?
Yes, correct.jbeale wrote:I gather the M12 lens holder is indexed to two holes on the camera PCB, rather than the existing lens mount?
I optimized the adapter to fit the widest range of lens characteristics possible. I carefully analyzed the clearance available on the Raspi stock lens receptacle versus a list of mating thread engagements and back focal distances (bfd) on 49 different M12 lenses ranging in focal length from f=1.7mm to f=50mm. Engagement and bfd are not standardized so the lenses vary a lot in that regard. A common bfd is 6mm or 8mm, but some are as short as 3.3mm. The flange distance (that is, the length from the last thread toward the object, back to the focal plane) which governs the length of thread engagement also varies.jbeale wrote:I am wondering about using very short focal length M12 lenses with a back-focal distance small enough (few mm) that it would require removing the existing M6 lens housing from the sensor chip.
Get an M12x0.5 tap here: http://www.use-enco.com/CGI/INSRIT?PMAKA=319-5883 Or make your own tap by grinding flutes onto a (cheap throwaway but metal) lens. You'll want a tapping guide to get the threads started straight, but if you're printing 3D I suppose you can just print yourself one of those as well, while you're at it.rleyden wrote:This part would simple and cheap were it not for the threads. No 3D printer that I'm aware of can directly print threads that fine.
jbeale-Could you mate a 3D printed part with one of these? http://www.m12lenses.com/M12-Lens-Holders-s/61.htm
Get an M12x0.5 tap here: http://www.use-enco.com/CGI/INSRIT?PMAKA=319-5883 Or make your own tap by grinding flutes onto a (cheap throwaway but metal) lens.
Several things about this prospective improvisation worth noting:rleyden wrote:Could one re-position the plastic camera onto a plate that has holes for the new housing?
Here's the poor man's version costing less than £5rleyden wrote:<snip>
However, I was hoping for something closer in price and materials to the camera and lenses (Ebay, made in China quality). </snip>
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.mmiller wrote:http://wiki.raspberrytorte.com/index.ph ... odifcation
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.htbwmedia wrote:Seeing the name M12 caught my attention ...
I totally agree, removing the lens in the module is far less distructive, but I have some of the lenses I have are very fast and I didn't want to encounter vignetting on the casing.rkinch wrote: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.mmiller wrote:http://wiki.raspberrytorte.com/index.ph ... odifcation
I'm pleased with the results so far. High optical zoom / narrow field of view is easy to achieve (of course that comes are a price / reduction in depth of focus).jbeale wrote:have you posted any other example images anywhere?
That typically won't happen because digital camera lenses should be designed with very different front vs back focal lengths, because digital sensors limit incoming ray angles. Even very short focal length M12 lenses have a small exit aperture that won't be stopped by the leaving the stock M6 receptacle in place. Consider how you can have a f=2.2mm lens with a 4.8mm back focal distance, like the Edmund 55569:(http://www.edmundoptics.com/imaging/ima ... nses/55569)mmiller wrote:... some of the lenses I have are very fast and I didn't want to encounter vignetting on the casing.
I've got some more lenses and camera modules on order so I'll give this a shot.rkinch wrote:Consider how you can have a f=2.2mm lens with a 4.8mm back focal distance
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