Microcontroller gives you more control of your camera lens

Here’s one way to get more control of your camera lenses. [Vladimir] built an Arduino-based pass-through ring (translated) which intercepts automatic lens controls. It’s meant for use with the Canon EOS lenses which have their own electronics allowing control of things like focus and zoom.

It seems like part of the motivation here was to uses the lenses with other brands of cameras. But [Vladimir] does also talk about the possibility of improving on some of the sensors that don’t perform well in certain climate conditions (think of how crystal oscillators will drift as temperature changes).

The machine translation is a bit rough to follow, but it seems the adapter ring still uses the settings sent in from the camera but has the Arduino clone to translate them into a format that the lens is expecting. In addition to this there is a set of buttons on that small PCB beside the lens which allow for fine tuning the aperture.

This is a lengthy writeup, but there’s two more on the way that will help fill in the gaps of how this hack works with different lens models, and some more tips on how to use it.

[Thanks Vasily]

CNC Light Painting

Light painting is a technique where a shape is drawn with a light source while a camera is taking a very long exposure shot of it. To do this well by hand would take a lot of skill, so I naturally decided to make my “light art” with a CNC router.

Using this technique, the LED light is treated just like an engraving bit would be under normal circumstances. The difference is that the Y axis is swapped with the Z axis allowing for easy movement in the plane that you see displayed in the picture above. This allows the old Y axis to switch the light on and off in the same way that an engraving bit is lifted to stop engraving and lowered to start (explained here). Instead of a bit though, it’s a switch.

Be sure to check out the video of the router in action (with the lights on) after the break: [Read more…]

Earning a merit badge with a pinewood derby photo finish

2/4 store-bought bodies

As a boy scout properly acculturated into the DIY philosophy, [Adam] really wanted to get his hands on the new Inventing merit badge. The merit badge required solving a problem, so of course a pinewood derby instant replay system was the obvious solution.

After thinking through a few solution paths like a radio-controlled camera that follows the cars, [Adam] settled on a system that would replay the pinewood derby cars crossing the finish line.  [Adam]’s father found a cheap and readily available Playstation Eye camera that can record 60fps video for this task. [Adam]  used a laser/photodiode/Arduino setup to detect when a car was crossing the finish line. A bit of Processing code supplied by his father records the relevant 60 frames of video and plays them at 5fps on a projector for the enthralled spectators.

We suspect that a similar setup could be used if [Adam]’s den wanted to try the rain gutter regatta or oft-forgotten space derby next year. Check out [Adam]’s instant replay system after the break, or join us in the comments for the inevitable argument over who had the best pinewood derby car.

[Read more…]

Lens adapter from a plastic soda bottle

This lens adapter makes a lot of sense if you’re looking to interface with cameras that don’t have an in-built mounting option. It uses the cap and threaded neck from a soda bottle (translated) to make the lens adjustable and removable.

In the past we’ve seen this hack using a lens cap with a hole drilled in it as the mounting bracket. But that’s only useful if the lens you’ve chosen actually has a cap to use. This method lets you cut the top off of a the soda cap and mount it on the camera. Now each lens can be affixed to the threaded neck of the bottle, allowing for some adjustment of the focal point by screwing the add-on in or out.

Obviously this would work well for macro or fish-eye lenses. But there’s all kinds of other options out there like adding a microscope lens adapter, or actually attaching quality optics to your device.