Civil Disturbance

I'm still stuck in Bangkok because opposition demonstrators have blocked the highway to the airport with their bodies and taken over the airport control tower. Haven't been away from the hotel because there has been a shooting and grenade incident in the city.



The Shangri-La Hotel is right on the banks of the Chao Phraya river, which is muddy but not at all smelly.





This is a "long tailed boat" as seen on Amazing Race Asia.



It's a car or truck engine (rear wheel drive) with the prop shaft actually living up to its name and extending into the water, with a propeller attached. The boat is steered by moving the entire (large) engine on gimbals.

Since the river isn't smelly, water taxis are actually practical.

Noodle Hottie

It's Noodle Hottie!



You gotta love the people who thought up this imagery to sell instant noodles! sure beats Ate Shawie and her spiel about nutritious Lucky Me.

On the other hand.. anti-government protesters have overrun the Bangkok airport and all flights are cancelled.. so I don't know if I'll be able to go back home to Manila later today. Bad news!!

I've been in Bangkok since Sunday night for a couple of client engagements. I'm in the Shangri-La hotel which is right on the banks of the Chao Phraya river (it's the semi-circular building in the lower center of this Google Earth image):



Hotel driveway:


View from my room:


Boat terminal by night:


One of the boats plying the river:

Not So Good Ghetto Ring Flash

Had a chance to work on my throwaway flashes from disposable cameras.



Learned a few things.

First, six disposable flashes in parallel draw a lot of current!

The flashes were charging up too slowly off a single 1.5V AA battery, so I decided to use a 6V gel cell I had lying around. Of course I had to somehow reduce the 6V to around 1.5V so that my flashes don't explode. My "solution" was six 1N4001 diodes in series; their forward voltage drop equals 4.2V, which brings down the gel cell's 6V to a safer 1.8V. Close enough.

What I noticed (the diode string is at the bottom-left of the picture) is that while the flashes were charging, smoke would emerge from the diode string! turns out the solder joints were melting!

To Dennis: now we know where the energy lost in the diode forward voltage drop goes. It becomes heat! lots of heat!

Bad news, I paralleled the triggers on all the flashes, and shorting it to ground only fired one of the flashes. I think the flashes have to be triggered separately.

Which means this article in DIY Photography, which so optimistically shows the flash triggers in parallel, is wrong.

OTOH, the article does mention you may need more than one slave. Oh well.

Cheap and Dirty Flashes

I got eleven flash circuit boards from The Electronics Goldmine. They were on sale for $0.79 (79 cents, or PHP 38) each. I bought ten and got eleven.



Each one has a 160uF or 120uF photoflash capacitor, rated at 330V, a tiny inverter, and flash circuitry. It only needs a single 1.5V AA battery to operate. The process is simple: put the battery in, with positive facing the circuit board, depress the metal "diving board" switch on the PCB itself to charge up the capacitor, then short the two dangling wires to fire the flash.



Trivial! I think it's about Guide Number 6 to 8. Quite minimal, but people have made super cheap DIY ring flashes out of these babies.

For my purposes, I'll put five flashes into each ring flash (made from the bottom of a KFC plastic meal bucket). This will also give me two semi-powerful flashes for my ghetto studio.

First order of business was to remove the battery clips, permanently short the flash power switch, and wire the flashes together. I also have to parallel the trigger wires so that the five flashes can be fired simultaneously. So far I've only done the first two steps:



If I'm lucky, I'll get some results this weekend!