Jennette Fulda is a fellow resident of the Stutz building. She approached me some time ago to take some pictures for a book she was writing on the incredible weight loss journey she’s been on…

The thing I remember most was when the publisher sent me the contract, it was titled “Half-Assed Photography Contract” (It’s more common than you think)

New York Times Article

I recently received a copy from the publishers, and from Jennette herself - thanks!
I urge you to go check out her blog, it makes for some entertaining reading!
PastaQueen

Now go out and buy the book!!

Last year I covered a wedding at the Sanctuary in Zionsville, IN. The marketing staff got in touch recently to ask permission to use some of the images on the Sanctuary website.

http://www.nanoel.com/page_detail.php?page_id=78&page_type=gallery

I’m in there amongst some of the other images.
It was a great venue, always nice to be able to shoot natural light at a wedding.

I just found this clip on Youtube - awesome!

It makes me really happy to see that someone has got the plans working - great stuff.

I’ve been asked to write an article for Make magazine on MIDI controllers using lasers and light. It’s come at the right time, as I’ve been meaning to try out the Sharp GP2D12 sensors I bought from Trossen Robotics. Anyone that has played a Roland synthesizer with a D-Beam controller will recognise these immediately. They fire out a pulse of IR light at 25Hz and then triangulate the position of the reflected dot to get a distance measurement.

Having played around with them for a while, there are two problems that need to be addressed before they can be used for musical applications:

The first is that the output can be noisy - this is in part due to the fact that quite a lot of current is drawn every 40ms when the IR LED is fired - this can get into the output signal as a spike. First off a 300uF tantalum cap and 0.1uF regular cap can be put across the power rails close to the sensor input - this helps to smooth the power going in. Additionally this basic filter circuit can be put across the output to smooth out any remaining spikes.

[Circuit -coming soon!!]

Also only sample the output every 40ms or so, as the output is only updated this often. It’s also possible to filter in software like this:

forever
{
while (!sample_available())
{
do_something_else();
}

average = (average < < 3) - average + get_sample();
average >>= 3;
// do something with the average here

}

This gives each sample an exponential decay.

The second problem is that the output from the device is non-linear - so we need to apply a ‘linearization’ to the output. Thankfully someone has already done the hard part for us - the functions are as follows:

GP2D12:

Range (cm) = (6787 / (V - 3)) - 4

GP2D120 (long range):

Range (cm) = (2914 / (V + 5)) - 1

[Taken from http://www.acroname.com/robotics/info/articles/irlinear/irlinear.html]

Applying this function as either integer or floating point math helps in getting a value that can be further scaled to modify MIDI pitch bend (0-16383), or continuous controller information (0-127)

One final tip - be careful where you place the sensors - putting them too close to a side wall, or in the wrong orientation can affect the reading accuracy, but when used properly these are a valuable addition to any MIDI hackers toolkit.

The trouble with Windows…

For many years I’ve been a happy (albeit slightly frustrated) Windows user. I felt safe in the knowledge that whatever problems came my way I had the skills necessary to pop the hood on XP and tweak a few settings to get through the day.

Not any more.

I recently bought a new laptop. In retrospect I should have researched a bit harder before I bought it, but I thought that using the same model at a client site for 3 months would have been research enough. True it didn’t have Bluetooth (despite being told otherwise by the salesman) and it had one of those new fangled Express Card 54 slots, so my lovely Cardbus Indigo sound card wouldn’t work, but that wasn’t enough to put me off.

This one however, had Windows Vista.

I really really want Vista to work out – I really do – my future as a Windows developer really depends on Microsoft pulling off this new release of their OS. The trouble was it just didn’t work with what I wanted to do.

None of my laser show software would run – “sounds like a problem with the software” – one helpful Vista supporter wisely told me on the forum. Yes thanks for that, but it doesn’t help me that the vendor’s customer base is majority XP and they’re (quite rightly) not going to waste resources on supporting just little ol’ me.

Network file transfers seemed doggedly slow as well – it took Vista 20 minutes to work out that it was going to take 4 minutes to copy the files I wanted. Nice.

I’m 38 years old, and the more years I clock up, the more I begin to realize that my time on this planet is limited. In the heady days of my youth I would have thought nothing of pulling an all-nighter just to get the OS to recognize some new and esoteric piece of hardware.

Not any more.

I need stuff done, and I need it done now.

So sorry Vista, you gotta go…

This is where the fun really begins. My laptop is a ‘Vista’ laptop – which means that the manufacturer and Microsoft do not provide or support drivers for XP. All the hardware ID’s have been sneakily changed so that the audio driver (for example) on the XP version of the laptop will not install on the ‘Vista’ laptop.

So I spent 3 joyous days rewriting driver installers just to get the hardware to run under XP.
I chose XP service pack 3 – something else that I regret. I’ve installed this version of XP on 3 machines, and they all exhibit freezing issues. One just loses network connectivity every hour for about 5 minutes – and I can’t for the life of my work out why.

Reverting to SP 2 seems to address this issue, but leaves me open to security holes…

Hmm… Damned if you do, and damned if you don’t.

And the reason for this post?

I got home last night and Outlook 2003 (the fast Outlook, unlike Outlook 2007) suddenly lost the connection to Exchange. Nothing I could do would restore the connection. The Exchange server was running, and visible on the network – all firewalls were configured to let the traffic through – but Outlook refused to connect.

Sheesh.

Thank goodness for Norton Ghost – (even though that has become suspicious bloatware in the last 3-releases). I dug out my restore DVD and booted up the recovery manager. After 4 minutes restoring my OS I finally got Outlook to work again.

I’ve been toying with the idea of getting a Mac, but when I think of all the additional expense of (re) buying my software I soon forget about it.

One thing is for certain, we live in troubled times.

Someone said to me recently “computers shouldn’t get less efficient as technology improves” and I’ve got to think that they’re right.

Footnote: Why I love embedded microcontrollers.

My laser harp uses an Arduino to drive the laser, scanner and sensor. It’s pretty efficient code (even if I do say so myself) and uses timer and hardware interrupts so that the MPU only works as hard as it needs to. I dread to think how well this kind of system would function under Windows.

It gives me a warm fuzzy glow every time I switch it on, and it just *works*…

…and it wouldn’t be a laser show without the liquid sky effect.

Last night we went shooting some footage for MakeTV and moved the harp to Anton Phibes’ secret underground lair..*

This was the first time we’d had harp set up in a proper venue, and it looked pretty amazing. We also took along the my homemade display scanner for a bit more p’zazz.

*Google:The Abominable Doctor Phibes

On the show it looks effortless, but in real life it can take a little longer to make the TARDIS appear…

Today is the birthday of the LASER beam - it’s 48.

From Wikipedia:

The first working laser was demonstrated on May 16, 1960 by Theodore Maiman at Hughes Research Laboratories.[2] Since then, lasers have become a multi-billion dollar industry. The most widespread use of lasers is in optical storage devices such as compact disc and DVD players, in which the laser (a few millimeters in size) scans the surface of the disc. Other common applications of lasers are bar code readers, laser printers and laser pointers.

Google did a nice logo today - spelling out “GOOGLE” with lasers and mirrors.

Which I will put here until someone from Google tells me to remove it.

I made some progress today - it looks like the majority of the components used in the PixArt hookup here:

http://www.kako.com/neta/2007-001/2007-001.html

Are for creating a clean 25Mhz clock signal from a bare crystal. If I buy a crystal oscillator, in place of a bare crystal, then I don’t have to worry about any of that stuff, I can just plug the output from the oscillator straight into the sensor.

I have to film the laser harp for MakeTV this weekend so I have to wait until that’s complete before trashing the WiiMote to get the camera out…