Geeky

~Cheap and tiny 3D printer – The “Printrbot Simple”

Wednesday, May 1st, 2013
Photo of the Printrbot Simple
If any y’all have thought of building a 3D printer and have been waiting for a kit to reach your low cost and complexity threshold, this new “Printrbot Simple” might be the one. It’s from the folks who made the “Printrbot Plus” I’ve been having fun with for a while, but is tiny in comparison and costs $299 for the kit ($249 for a very short time as a beta).

Read more on their page, Introducing the Printrbot Simple.

To my eye, the design looks very interesting. Most parts I’ve printed would fit fine within its 100x100x100mm (3.5″ cube) build envelope, and something that small would be nice and portable.

Just figured I’d pass it along while the discounted beta price is in play.


Fitz and the Tantrums Video: “Out of my league”, crazy lo-fi 3D with Kinect and RGBDToolkit

Tuesday, April 23rd, 2013

Fitz and the Tantrums – Out of My League from Jordan Bahat on Vimeo.

My friend Jordan directed this music video for the band Fitz and the Tantrums (released on 4/22 on VH-1 and on the band’s web page and on vimeo in better quality), and I got to help plan and execute a technically unorthodox portion of the shoot. It’s a little odd for me to be involved on the production end of a project and to not work all the way through post-production (on films, post often lasts for more than a year) –but it was fun to shoot a bunch of stuff, hand it to the producer, and then see the final result weeks later. Now I know a little better how production folk must feel. Kudos to Jordan and producer Taylor for seeing the project through to the end.

A preview of the depth map as it was being recorded to a laptop during the shoot.
A preview of the depth map as it was being recorded to a laptop during the shoot. The different colors represent the depth at each point. Black spots represent holes in the data –areas in which no depth was recorded.
At around 30 seconds in, you’ll start to see the lo-fi 3D imagery I helped capture and visualize –point clouds and wire-mesh renditions of members of the band, rendered from various virtual camera positions.

The data was shot head-on from a fixed camera position1, using a Canon 5DmkIII DSLR to capture video and a Microsoft Kinect sensor connected to a laptop to capture a video depth map. The DSLR and the Kinect were locked to one another with a 3D-printed mount. Jay Trautman2 (thanks!) operated the laptop while I manned the DSLR.

The depth information for each pixel (or ‘D’) captured on the Kinect was recorded and later paired with the video info for that pixel (RGB) using a piece of free software3 called RGBDToolkit. It’s fun to play with. If you’ve got a Kinect and a video camera, you might give it a try.

There were some even-more-ambitious 3D data capture techniques at play during the shoot, involving an array of kinects and cameras (thanks Cedric!), which I’ll talk about another time. The non-3D shots were also captured on a Red Epic camera by D.P. Andrew Wheeler and his team.

My cousin Jenny did some great storyboards for the video, if they make it into her portfolio I’ll link to ‘em. A ton of other people worked on the video. I’ll link to the full credits soon if I can find them.


  1. i.e. the camera was locked into position using a tripod []
  2. I worked with him previously on The Man with the Iron Fists []
  3. free as in beer and as in “MIT license” []

Designed a part for my 3D printer – home manufacturing FTW

Saturday, March 16th, 2013
Screenshot of the model in Autodesk Inventor Fusion
I’m feeling pretty happy about this one. It’s my first somewhat complicated CAD design, and it works well. It’s a mount which holds a blower fan next to the extruder on my 3D printer and aims a stream of air towards the plastic as it prints, to cool it quickly so that the next layer is printed on a solid base.

There’s something really satisfying about measuring the dimensions of an item using calipers, sketching out a part meant to fit, designing it in a computer, printing a copy, fitting it, making changes to the design, fitting it, and ending the process with a working part that fills a need.

The files for printing and additional images are available on thingiverse.

photo of the blower fan mounted to the Printrbot+ extruder
photo of the blower fan mounted to the Printrbot+ extruder


Inexpensive and familiar-looking studio monitors coming to Monoprice

Monday, January 28th, 2013
I always think of online retailer Monoprice.com as a place to buy good and inexpensive audio and video cables, but they’ve been branching out. Recently, they’ve added microphones, an 8-channel mixer with USB IO, a $390 27″ IPS1 WQHD2 resolution monitor (which may be using the same panel as Apple and Dell’s 27″ IPS displays), and an interesting pair of audio monitors to their lineup. These are all the kind of items I use to outfit editing stations, so I’ll be keeping an eye on their new items. But I’m especially curious about those audio monitors.

That’s because the Monoprice “5-inch Powered Studio Monitor Speakers” look suspiciously similar to M-Audio’s BX5 monitors –the size and specifications are nearly identical3. But Monoprice’s sell for 40-50% less money. Here’s a little comparison:

Monoprice:

  • 1″ silk dome tweeter, 30w amp
  • 5″ Kevlar cone woofer, 40w amp
  • freq response: 56Hz-22kHz
  • crossover freq: 3kHz
$165.78 a pair

M-Audio BX5-D2:

  • 1″ silk dome tweeter, 30w amp
  • 5″ Kevlar cone woofer, 40w amp
  • freq response: 56Hz-22kHz
  • crossover freq: 3kHz
$299 a pair (MSRP. $230 street)

The similarity leads me to wonder whether Monoprice and M-Audio are buying from the same factory. If so, I wonder if the speaker was originally designed by M-Audio or whether the factory sells the same model to all comers, and each company just changes the look of the enclosure. I’m always curious about manufacturing and the provenance of products, so I’m very interested to know more about how (if I’m right) both companies ended up selling almost the same speaker with a different housing and at very different price points.

Were I building an editing station from scratch right now, I’d probably be checking reviews of Monoprice’s mixer, their 27″ IPS monitor, and their audio monitors (once they are all released). These are key components of any editing system, and I’ve definitely spent beyond those prices kitting out my setup of hardware that has roughly equivalent specifications.


  1. “In Plane Switching, a very nice type of LCD panel. []
  2. 2560×1440 []
  3. There is one minor difference I spotted between these models, and that is that the Monoprice monitor includes a “four-position high-frequency bias selector switch”, which is not a feature of the M-Audio BX5-D2. But previous versions of M-Audio’s BX5 did include such switches, so maybe Monoprice’s monitor is more of a match to M-Audio’s older monitor? []

The brief first flight and untimely end of my quadcopter

Thursday, January 3rd, 2013
Perhaps that title is a bit dramatic. As best I can tell, one of the engines is bad, shut down in flight, and then its pylon snapped free from the wing. The copter/plane is all patched back together now, and will be ready to fly again as soon as I receive a new motor and two replacement propellers.

Video was captured using a GoPro camera mounted to the Quadshot Mocha multicopter’s built-in tripod mount, and an 808 keychain camera #11 with D lens velcro’d to the Gopro (accidentally rotated to the vertical).

More to come.


test post (new server)

Wednesday, January 2nd, 2013
There’s a new server in town.

I swapped out the used and ancient IBM Thinkpad T41 Centrino laptop that was this server for a used Thinkpad T62 Core 2 Duo laptop. Hopefully there’ll now be more stability and faster page loads.


A collected list of links to Blackmagic’s CEO’s camera shipping updates

Friday, November 16th, 2012
Here’s a table of links to all of Blackmagic CEO Grant Petty’s posts to his company’s forums regarding the Blackmagic Cinema Camera‘s manufacturing delays. Apart from the whole “you’re not getting your camera yet” part, they’re a fun read; the sort of engineering details one gets access to as a backer of a kickstarter project. I found the 11/7 update to be full of particularly interesting details.

9/25/12Update on Camera Shipments
10/19/12 Camera Shipping Update: 10/19
10/29/12Camera Shipping Update: 10/29
11/7/12Camera Shipping Update: 11/7
11/15/12Camera Shipping Update: 11/15
12/14/12Camera Shipping Update: 12/14


recent 3d prints: gopro naked housing, panelolu LCD panel housing

Tuesday, November 6th, 2012
3d-printed gopro housing
This naked gopro housing fit perfectly on the various gopro mounts. I need to modify the design to get it to better fit the gopro with Wifi Bacpac attached.
LCD panel and control housing for reprap
LCD panel in progress to control my printrbot+ without a computer.

The dynamic range of the BlackMagic Cinema Camera does not disappoint

Monday, October 29th, 2012
I got my hands on a prototype BlackMagic Cinema Camera for a couple of hours last week. To cut to the chase, I was blown away by the dynamic range recorded by this camera, was impressed by the level of detail in the images, and I didn’t find the super-16 sized sensor to be nearly as much of a limitation as I’d expected. Using great Canon EF-mount lenses I already own, I was able to execute the kind of images I wanted, and at better quality than the video from any DSLR.

If you haven’t yet heard of the BlackMagic Cinema Camera (henceforth BMCC) and you are a filmmaker, it’s time for you to read up on it, watch a review, and view a great comparison between the BMCC and the Canon 5D mark III DSLR. As long as BlackMagic manages to ship the BMCC in bulk, people will be making tons of very good looking low-budget films using this camera, and it’s going to displace many DSLRs and prosumer camcorders. The image quality for the price is unmatched.

Did I mention dynamic range? Here’s a still frame from a clip shot at the latter end of dusk. The camera was set to its minimum ASA setting of 200, which explains why the initial image looks very dark. Because The BlackMagic Cinema Camera records each 2.5K frame of video as an individual 5Mb 12-bit raw file, and because its sensor captures a staggering 13-stops of dynamic range, there is much information in the shadows (and highlights) of the image that can be revealed when adjusting the image. I knew this, but was still amazed to see just how much information was waiting in the shadows. Click the ‘graded’ link below the image, drag the green handle to the left and right, or tap around within the image if on a mobile device, to compare the original image to the graded version.

ungraded bank
graded bank

Here’s another still, from a clip shot slightly earlier in the evening. It initially looked unsalvageably dark, which is pretty close to how it looked to the naked eye in real life. I adjusted the image and warmed the color temperature a little bit to see how far I could pull it. The result I’m going to call “night-for-day shooting”! (again, click the ‘graded’ link or drag the handle to compare the original and processed image).

ungraded police car
graded police car

One more before-after comparison; I do prefer the stark, silhouetted look of this as shot, and our model Erik really knows how to create drama when striking a pose –but if it were part of a scene in a film in which the actor’s facial expression was important, it’d be nice if there were detail in the shadows to bring up. With the BMCC, there is that option.

ungraded EJ
graded EJ

My biggest concern with the BMCC related to its sensor size. I was worried that, in order to shoot a decent medium shot of an actor while throwing the background slightly out of focus, I’d need to back away from the actor so far that the image would take on a distant, flattened, surveillance-ish feel. But this shot reassured me that this wasn’t going to have to be an issue.
00819984.Mov-1
Canon 24-105mm f4L at 24mm (58mm equivalent considering a 2.4x "crop factor"), shot from a few feet away. The shot has the kind of immediacy and presence I was worried would be difficult to achieve on the BMCC’s small sensor, but it wasn’t difficult at all. This shot’s been slightly graded in DaVinci Resolve and output at 1080p resolution, click to see a larger image to wonder at the detail level. I did play with the image a bit, and noted that there was plenty of information in the shadows of the eye sockets, so if this were a crucial shot I could track a couple of "power windows" to the eyes and reduce the darkness of the shadows.

It was great to get a chance to play with this camera and evaluate its potential. It exceeds the hype. We’re going to see good things coming from BMCCs, assuming BlackMagic can get them shipping in bulk soon. And I hope they do, because a couple of days after I shot these tests I sold off a piece of equipment I’d deprecated and pre-ordered my BMCC.


Pink Prints

Friday, September 28th, 2012
Img 1674
The Mars Curiosity Rover, model created by ThePlanetMike (downloaded from here)

Img 1673
Pink Flamingo, model created by makerbot. (downloaded from here>
Img 1677
The flamingo in its rightful place. When my xacto knife arrives I’ll have a better shot at removing the brim from the edges.
As always, click any image to see it at full size.