Monday, January 23, 2012

iPod Macro Photos

I ordered a couple of small lenses from Surplus Shed (#L4471) to try out as macro lenses for the iPod Touch. They arrived today, so I tried taking a couple of test pictures with them taped to the front of the iPod. I was a little disappointed, as I was hoping to get tighter close-up with it. So, naturally, I stacked the two of them together to try it that way. This is the result.

These are images of the pixels on my monitor (~92 px/in ) taken with the iPod and my DiMage Z2 in SuperMacro mode. The image resolution ends up being very similar (in this test each screen pixel ends up being about 12 pixels across), but the Z2 does a better job overall, with better color and, of course, more pixels overall. The iPod does pretty good though, certainly acceptable for quick shots of stuff. I'd like to try another lens with a different focal length (these are 51mm) to see if I can get up closer.

Here I got a picture of a US penny. The Z2 will take better macro pictures than this, but I didn't put any effort into setting up, I just snapped a handheld auto-focus picture with ambient light. But I did the same thing with the iPod, so it's a reasonably fair comparison of taking a photo under these conditions.

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Thursday, January 19, 2012

Web-attached pan tilt camera

With some help from Brandon and Ben I got the mechanics for the pan tilt camera rig going. The servos attach to an Arduino which is connected to a computer running a Windows web service that provides access to the camera.

I had an issue with the movement speed initially, and had to update the Arduino code with some position speed ramping. That went well and it is moving more smoothly. It flops around a bit, but I think that is mostly the slop in the mechanism.

The web service supports tagging of positions so that interesting views can be labeled. Once labeled a single button press takes the camera back to the associated position.

I will post some video of it in action soon.

Saturday, January 14, 2012

Mail Rings

I'm working on a 4 in 1 mail wristband as a gift, and I thought it would be interesting to try welding and brazing some rings. This is the result, prior to an acid bath and more polishing. Unfortunately I ran out of oxygen before I could get very far with the brazing, and I didn't manage to close a ring with the brazing.

I deliberately picked some 'worst case' rings, which had wide gaps. These were fairly easy to close, and I think that well-formed rings would come out very nice.

I wouldn't want to do more than a few hundred like this, but I think smaller pieces shouldn't be too bad.

Wednesday, January 11, 2012

Tippy forge

Here are a couple of videos of the tippy forge I've been working on for the Omaha maker Group. At this point it just needs the frame to hold it and a handle to make it easy to tip. There is a little leakage from the input that we need to get sealed up, but it works quite well so far.

Motor demonstration rig

One of the interesting projects from the Omaha Maker Group meeting on Jan 10. Ben put together this little motor demonstration rig with a couple of magnets, a 3D printed frame, and the armature from a commercial motor. Here he is just holding a couple of wires against the commutator as brushes. It's interesting to see the effect of adjusting the brush positions relative to the magnets.

Tuesday, January 10, 2012

Arduino Fio and other bits

Received an Arduino Fio and some other bits in the mail today. I was planning to use this for the Omaha Maker Group Makery Monitor Micro (OMGMMM), but I did not pay close enough attention when ordering and pdid not notice that it doesn't support the USB serial. I didn't have the budget for the XBees for it, but I guess I will have to do that sooner rather than later, as the web page and web services for it are getting close to beeing deployable. It even supports driving servos via the web service.