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The Randomizer

Posted 2011.03.24 21.43 in Computers/Internet/Technology by Stephanie

After 3 months of on-and-off working on my thermostat project, it seems kind of funny to pop this one out in a couple hours in a single evening.

My second from-scratch Arduino-based project, is more or less an electronic version of the ‘Magic 8-Ball‘. Press one of the buttons and the screen fills up with random characters or numbers as it ‘randomizes’ ¬†itself, then after you release the button it presents the result on its LCD screen.

It has around 20 8-Ball-ish responses, though they’ve been edited to fit on the screen, modified a little to fit the format of The Randomizer speaking in the third person. For no good reason whatsoever.

Eagle-eyed obsessive readers (I know who you are) will recognize the enclosure and button board are from the 0.1 version of the thermostat. Having 4 buttons (the little one is just a reset button) and the 8-Ball only using one of them, I quickly came up with a use for the other three.

Forgive my nerdiness… when pressed, buttons 2, 3, and 4 will produce the result of rolling percentile, 1d20 and 1d10 dice instead of an 8-Ball phrase.

While on the subject of geekiness, for some extra geek points (and battery savings) the LCD screen’s backlight only comes on when in use, then after 30 seconds of disuse the backlight switches off.

Each of the 4 buttons goes to a digital pin, and there’s still some additional pins available so it could be expanded further. Though even with only the four existing buttons, it could be expanded by reading multiple buttons at once.

The Randomizer runs on 4 AA batteries, which will probably last for 2 or 3 kilo-whiles. You can build one of your very own; all you need is an Arduino, an LCD, a couple buttons and a box.

Here’s the source code, for your enjoyment and tinkering pleasure.

Hanimex Rangefinder

Posted 2009.09.30 22.58 in Hobbies, Photography by Stephanie

So I ran a test-roll through the Hanimex today. I took it partially apart last night and figured out that without a battery, it was probably running the shutter at full speed. Full speed is probably 1/300 sec based on the Hanimex ZF35 which looks very similar. So knowing (or guessing) that the shutter speed was 1/300 I calculated the aperture based on the Sunny-16 rule, and went from there.

The results were not bad – the lens seems fairly sharp and I’m pleased with the results. I’ll have to get a battery for it and see how it reacts in its normal mode, aka aperture priority. It has a CdS “electric eye” and can allegedly adjust the shutter speed based on the available light and selected aperture. I’d have been happier if it was fully manual, i.e. if it had a shutter-speed selector rather than a film speed selector. Nonetheless, it’s a wonderfully small and lightweight 70s rangefinder and seems to have a fairly decent lens!

Canonet Test Roll

Posted 2009.09.12 8.15 in Hobbies, Photography by Stephanie

I processed the first roll shot with my ‘new’ Canonet QL17, and the results were… mixed. Almost the entire roll came out under-exposed, so I have to try and figure out why. Two possibilities come to mind, the first being that the Electric Eye is not working right, i.e. giving incorrect metering, and the second being that I &#%ed up the developing somehow.

I’ll have to do another roll and be sure to vary the exposures so there are some different levels I can compare. The Electric Eye was designed to use the now-verbotten 1.35v mercury battery; the alkaline replacement is 1.55 volts and that might be enough to throw the meter off by one or two stops. And alternatively, when I decided to process the film it was late at night and I’d enjoyed a few adult beverages, so it’s entirely possible that the camera is fine and I baffed the whole thing up by mixing the chemicals wrong or getting the timing wrong.

I tried to find a book yesterday at Chapters that would include some info on developing film, but literally every single book in the ‘photography’ section includes the word ‘digital’. Even the darkroom books are all ‘digital darkroom’. ¬†Ptooey!

Anyhow, here are a few results from that first test-roll.

Because the whole roll had come out under-exposed, I was forced to push the exposure when scanning the negs and that affected the quality somewhat. It’s not unlike going from neg to print, you can fix some problems by varying how you expose and develop the paper.

Also, I was more interested in rushing through the roll so I could ensure that the camera was working, and didn’t think much (at all) about actually composing good shots. I’ll have to work on that – still trying to re-train my eye for photography.

Cheers!