When one thinks about microscopy, it seems to be mostly qualitative. Looking at a slide teeming with bacteria or protozoans is less about making measurements and more about recognizing features and describing their appearance. Not all microscopes are created equal, though, with some being far more optimized for making fine measurements of the microscopic realm.
This 3D-printed confocal laser scanning microscope is a good example of an instrument for measuring really small stuff. As [Zachary Tong] points out, confocal scanning microscopy uses a clever optical setup to collect light from a single, well-defined point within a sample; rather than getting an image of all the points within a two-dimensional focal plane, the scanning function moves the focal point around through the sample in three dimensions, capturing spatial data to go along with the optical information.
The stage of [Zach]’s microscope is based on OpenFlexure’s Delta Stage, an open-source, 3D-printed delta-bot motion control platform that’s capable of positioning samples with sub-micron precision. Above the stage are the deceptively simple optics, with a laser diode light source, an objective lens, and a photodiode detector behind a pinhole. The detector feeds a homebrew trans-impedance amplifier that captures data at millions of points as the sample is moved through a small three-dimensional space. All that data gets crunched to find the Z-axis position corresponding to the maximum intensity at each point.
It takes a while to gather all this data — up to several days for even a small sample — but it works pretty well. [Zach] already has some ideas for reducing noise and speeding up the scan time; perhaps a stage based on DVD parts like this one would be faster than the delta stage. We look forward to seeing his improvements.
We’ve seen pinhole camera builds before, but this new one looks interesting. The Scura is a new open-source design for a pinhole camera that shoots on analog 35 mm film. It is all 3D printable except for a handful of screws, magnets, and the pinhole itself, which is laser cut. The cool and unusual part of the design, though, is the curved film holder, which produces 60 mm by 25 mm (2.3 in by 0.98 in) panoramic images that are sharp to the edges.
Taking a picture is as simple as tapping a screen. Drawing a memorable scene, even when it’s directly in front of you, is a different skill entirely. So trace it! Well, that’s kind of hard to do without appropriate preparation.
[bobsteaman]’s method is to first whip up a pantograph — it tested well with a felt marker on the end. Next, he built a camera obscura into a small wood box with a matte plexiglass top, which didn’t work quite so well. A magnifying glass above the camera’s pinhole aperture helped, but arduous testing was needed to ensure it was set at perfect position for a clear image. The matte plexiglass was also thrown out and, after some experimentation, replaced with a sheet of semi-transparent baking paper sandwiched between two pieces of clear plexiglass. The result is hard to argue with.
If you’re looking for the technology here, you won’t find much. There’s no lens, no shutter, and no electronics of any kind in [Mick Farrell] and [Cliff Haynes]’ Straw Camera. This is literally a box full of drinking straws standing on end, with a sheet of photo paper behind it. Each straw sends a spot of light that represents the average hue and luminance of its limited view of the subject directly to the film. The process of making an exposure consists of composing the scene, turning out the lights, loading the camera, and setting off a flash.
The resulting images are defocused but recognizable, like seeing familiar sights through a heavy fog. The straws make a strong texture over the ghostly image of the subject – indeed, the straws are the only thing in focus. The fact that the straws don’t form a perfect honeycomb due to settling and imperfections in the bundles is jarring at first, but as you see the images you get used to the extra texture.
When we first saw this, we wondered about the possibility of putting a simple photosensor at the bottom of each straw to capture similar images digitally. The TCS3200 would be about the right size, but given that there are about 32,000 straws in the bundle, the BOM might get a little out of hand. Still, a scaled down digital straw camera might yield some interesting images.
With digital cameras in everything and film slowly disappearing from shelves, everyone loses an awesome way to learn about photography. Pinhole cameras allow anyone to build a camera from scratch and also learn about those crazy f-stops, exposure times, and focal planes that Instagram just won’t teach you. [Matt] put up a great tutorial for building your own pinhole camera, and the project looks easy enough for even those who are still playing around with their cell phone cameras.
For film, [Matt] used 120 film, a medium-format medium that is sill available for purchase and processing in some areas. Because [Matt]’s pinhole is relatively large and made out of very thin material, the camera could take very large pictures – much larger than standard 35mm fare. If you’re using a smaller camera projecting a smaller image onto the film, 35mm would be the way to go as it greatly decreases the difficulty of finding film and a processing center.
[Matt]’s camera is constructed out of laser-cut plywood. Because he’s producing extremely wide images with his camera (6 x 17cm), [Matt] needed to curve the film around the focal plane of the camera to keep the entire image in focus.
The mechanics of the camera are simple – just a pair of knobs to wind the film and a small metal shutter. [Matt] added a shutter release cable to open and close the aperture without moving the camera and had a wonderful camera perfect for capturing either sirs and madams or Civil War battlefields.
While it seems that the digital camera is king, some people still love shooting with good old 35mm film – [Costas Kaounas], a high school teacher and photographer certainly does. He recently published plans for a great-looking 35mm pinhole camera over at DIY photography that we thought you might enjoy.
[Costas] put together a set of simple hand-drawn plans for the camera, that you can easily replicate with a bit of free time. The camera is built mostly from card stock, both in 1mm and 3mm flavors, also incorporating popsicle sticks and an aluminum can. The popsicle sticks are used to create a manual shutter for the camera, while the pop can is used to form the pinhole aperture.
It’s a pretty simple hack as you can see, with nary an electronic part to be found. It will take you a bit of time to construct however, since you’ll need to let the glue dry between certain steps.
Love it or leave it, you’ve got to admit that the panoramic shots it takes are pretty nice!
[Bshikin] built a pinhole camera out of Lego pieces (translated). It is a fully automated unit thanks to the integration of the NXT pieces. It took a bit of careful calculation to get the film spacing adjusted to match the focal length, and quite a bit of tape was necessary to keep light out of the film chamber. But in the end, it’s an amazing build that takes decent pictures. The software has settings for film size and speed, and takes care of exposing and advancing the frame at the click of a button. See for yourself after the break.