These days, camera lenses aren’t just simple bits of glass in sliding metal or plastic housings. They’ve often got a whole bunch of electronics built in as well. [Dan K] had just such a lens from Sigma, but wanted to get it working fully with a camera using the Canon EF lens fitting. Hacking ensued.
The lens in question was a Sigma 15-30mm f/3.5-4.5 EX DG, built to work with a Sigma camera using the SA mount. As it turns out, the SA mount is actually based on the Canon EF mount, using the same communications methods and having a similar contact block. However, it uses a mechanically different mounting bayonet, making the two incompatible.
[Dan] sourced a damaged EF lens to provide its mount, and modified it on a lathe to suit the Sigma lens. A short length of ribbon cable was then used to connect the lens’s PCB to the EF mount’s contacts. When carefully put back together, the lens worked perfectly, with functional auto-focus and all.
While browsing through an antiques shop, [Nick Morganti] came across a Kodak slide projector with an absolutely massive lens hanging off the front. Nearly a foot long and with a front diameter of approximately four inches, the German-made ISCO optic was a steal for just $10. The only tricky part was figuring out how to use it on a modern DSLR camera.
After liberating the lens from the projector, [Nick] noted the rear seemed to be nearly the same diameter as the threaded M42 mount that was popular with older film cameras. As luck would have it, he already had an adapter that let him use an old Soviet M42 lens on his camera. The thread pitch didn’t match at all, but by holding the lens up to the adapter he was able to experiment a bit with the focus and take some test shots.
Encouraged by these early tests, [Nick] went about designing a 3D printed adapter. His first attempt was little more than a pair of concentric cylinders, and was focused like an old handheld spyglass. This worked, but it was quite finicky to use with the already ungainly lens. His second attempt added internal threads to the mix, which allowed him to more easily control focus. After he was satisfied with the design, he glued a small ring over the adapter so the lens could no longer be unscrewed all the way and accidentally fall out.
To us, this project is a perfect application of desktop 3D printing.[Nick] was able to conceptualize a one-of-a-kind design, test it, iterate on it, and arrive on a finished product, all without having to leave the comfort of his own home. To say nothing of the complex design of the adapter, which would be exceedingly difficult to produce via traditional means. Perhaps some people’s idea of a good time is trying to whittle a lens bayonet out of wood, but it certainly isn’t ours.
Anamorphic filming techniques came about in the era of film. The aim was to record cinema-style widescreen footage on 3:2 aspect ratio 35 mm film. The way this was done was by using a lens that squeezes a wide aspect ratio to fit the format, and then a corresponding lens to squeeze it back on the projector. This allows for higher resolution than simply letterboxing onto the 35 mm frame and wasting the extra space.
Adam’s hack involves 3D printing a lens housing that pairs an anamorphic projector adapter lens with a Sony E-mount taking lens. Gears are set up so that both lenses can be focused together, rather than typical adapter setups that require the user to juggle multiple focus rings at once. This makes the rig much more usable in real shoots where there’s no time for messing about.
When you hear the term “extension tube”, you probably think of something fairly long, right? But when [Loudifier] needed an extension tube to do extreme close-ups with a wide-angle lens on a Canon EF-M camera, it needed to be small…really small. The final 3D printed extension provides an adjustable length between 0 and 10 millimeters.
But it’s not just an extension tube, that would be too easy. According to [Loudifier], the ideal extension distance would be somewhere around 3 mm, but unfortunately the mounting bayonet for an EF-M lens is a little over 5 mm. To get around this, the extension tube also adapts to an EF/EF-S lens, which has a shorter mount and allows bringing it in closer than would be physically possible under otherwise.
[Loudifier] says the addition of electrical connections between the camera and the lens (for functions like auto focus) would be ideal, but the logistics of pulling that off are a bit daunting. For now, the most reasonable upgrades on the horizon are the addition of some colored dots on the outside to help align the camera, adapter, and lens. As the STLs and Fusion design file are released under the Creative Commons, perhaps the community will even take on the challenge of adapting it to other lens types.