With all this discussion of various thermal centering devices, one should also mention Themi. No pretty pictures, just two bright LEDs and some sophisticated software that helps you find and stay in the center of drifting thermals. Takes a bit to get used to it, but I find that I either make a decision to move just before my Themi tells me to, or when I'm clueless in a shifty core, I just follow the bright lights and they lead me back to the lift. The nice part of the Themi system is that it takes almost no heads down time - you catch the LEDs out of the corner of your eye and adjust pretty automatically.

Combined with SYMs lift dots on your trace, makes it pretty easy (most of the time...)

Plus it's an IGC logger and GPS source. A bit awkward to download, but makes for a good backup logger.

Kirk
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