PSA

Jun 26, 2006 07:55

Compact fluorescents

Compact fluorescent lamps don't suck anymore. I had written them off after my parents got them when I was younger. At that time they weren't very white, flickered, and took a while to turn on. Today they don't seem to flicker, have a fairly good spectrum, and start up quickly. (They do get to about 80% instantly, it takes a minute to get to 100% but it's not too noticeable.) They also take about a quarter the power of a similarly-bright incandescent. By changing 300 W of lights in my primary room in my apartment, it should be the same heat effect as having more than two people leave the room. The glass globes on my overhead lights are now 109° F rather than 131° F with 100 W incandescents.

I was thinking of this in terms of keeping cool in an apartment with no AC, but the cost savings, at least, should be even better with AC. It looks like an average AC unit does about 2.5 watts of cooling for each watt of power you put in, so replacing a 100-watt bulb with a 25-watt one should result in a savings of 75 W + (75 W/2.5) = 105 W - that's more than the bulb itself. (Note: I am not a HVAC specialist.)

Focus

In completely unrelated musings, good old Gaussian blur is not the same as out-of-focus. Whereas Gaussian blur is convolution by a normal-distribution-shaped kernel, the blur you see in a camera is convolution by the camera's aperture, creating artful roundish dapples of light. After a discussion on Wikipedia's Talk:Gaussian blur, The result is apparently called bokeh. You wind up with bright circles (or hexagons or octagons) where bright points are out of focus. There's a GIMP plugin to do all this which works nicely. Still, doing it by hand I was able to go from


to
.

Beagle

In still more unrelated news, the Linux equivalent of Spotlight and Google Desktop Search, Beagle, Just Works with Ubuntu if you install it. Between this and alpha-blended windows with drop shadow, the look and feel of my home Linux box has caught up in major ways with Mac OS X.

graphics, egineering, photography, heat transfer, psa

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