Sunday, January 2, 2011

I’ve got the powa!

I’m slightly obsessed with my new Petzl Headlamp. It’s a Tikka XP2, which replaces a beloved old Zipka. It’s symbolically meaningful that the two lights were designed in different centuries. I loved my Zipka, with its cool little retractable headband, but it’s lost its (limited) oomph, is essentially worthless on the early-morning roads, and I thought it was probably time for something over one candlepower.

Tikka and Zipka lamps are identical, and I went for the Tikka configuration this time for two reasons: its traditional headband offers greater stability and comfort on the run, and it gives me the ability to pull the whole deal down around my neck as a temporary storage option. (I can pull the Zipka’s retractable string down around my neck, too, but it makes me feel like an Ottoman sultan struggling through his last few depressing seconds.)

Configured either way, the XP2 is a nice up-to-date headlamp, with multiple settings (Hi, Lo, Blink), a red-beam option for maintaining night vision as you grope for your pee bottle, and a little fresnel lense you can slide over the light to create a wider beam. Pretty cool, but not likely to excite my electrons.

It’s Petzl’s Core Rechargeable Battery that does that. More accurately, what I’ve been admiring for the last few days is Petzl’s OS, the free downloadable software that lets me control the Core. Using OS and the Core, you can create a regulated headlamp, one in which you specify the intensity of the beam the lamp puts out, which it holds for a known, inversely related, period of time, instead of gradually dimming to failure, which is what regulary batteries do. You can see roughly how this works on this screen shot.

This shows you that at full intensity, you get a beam that illuminates 40 meters ahead (about as far as the distance from home plate to second base, straight across the pitcher’s mound—a real boon to catchers trying to throw out runners in the dark) and the battery will need to be recharged after 4:30. As you adjust either the vertical output slider or the horizontal time to failure slider, the red line on the graph changes to illustrate the new reality, while the boxes at upper left and bottom center change to yield the new readings. You can create as many pre-set profiles for specific needs as you like. (As best I can tell, though you can recharge at any time by way of a USB cable, you can’t change to a different profile until you get back to the computer with your software on it.)

It’s presets I’m fiddling with at the moment. At 50 percent output, the values change to 28 meters and 9:45. At 25 percent, 20 meters and 19:00. At the minimum 4 percent, you get an 8 meter beam good for better than four days. (Petzl says the Core has been designed to be recharged 300 times, a lifetime it claims saves the use of 900 AAA alkaline batteries—a very good thing for multiple reasons.)

For running in the dark at my short distances, 100 percent is best, but for two weeks of hut-to-hutting in New Zealand’s summer, I’m pre-setting 60 percent, which gives me a more-than-adequate 31 meters (think from home to first) at an acceptable 7:45. Of course, I can always switch to battery-saving Lo at any time. And in a real pinch, I can remove the Core and go to three AAAs (these Petzls accept lithiums, unlike earlier models).

Here’s my quick chart of the Petzl power/time continuum:


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