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Hey, I'm an astrophysicist in high energy gamma ray astronomy. Or telescope sensors have hexagonal pixels. You website is awesome and helped a lot writing th
by maxnoe 8y ago
Hey,
I'm an astrophysicist in high energy gamma ray astronomy.
Or telescope sensors have hexagonal pixels.
You website is awesome and helped a lot writing the coordinate trafos and other stuff.
We always recommended it to everyone involved.
One switch I always wished it had was to switch to a cartesian coordinate system where x points right, y points up and negative coordinates are allowed.
- yellowapple 8y agoWhat drove the decision to go with hexagonal pixels? Sounds pretty crazy and cool.
- maxnoe 8y agoHistorically, the "pixels" are mostly round photomultiplier tubes. So the natural way to place those is a hexagonal grid. o o o o o o o The pixels are very sensitive, we can register single photons with a time resolution of half a nano second. Quite recently, some telescopes started using silicon photo multipliers, which are mostly square by design. But: The first telescope to use those also used light concentrators to increase the detector area and these have hexagonal entrance windows, so we also have hexagonal pixels. Physicists like symmetries, and light concentrators are more effective when round than square, hexagonal is a good middle ground.
- yellowapple 8y agoThanks for explaining! Makes sense.
- amitp 8y agoCool! Glad the page helped! On the implementation page the code supports both y-up and y-down, as well as negative coordinates. One of these days I should update the diagrams on the main page to support this too.