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Waterluviantoday at 7:09 PM3 repliesview on HN

False colour composites were something I was introduced to in high school GIS and did a lot of in undergrad remote sensing. It was one of those Eureka! moments for me in terms of developing a better understanding of signals and signal processing, as well as sensors and data collection. Ie. absorbing the reality that the way in which my eyes (or any optical sensor) see the world is not canonical. Vegetation is red, not green!

It was also just the COOLEST THING EVER to swap infrared bands in LANDSAT ETM+ imagery and watch vegetation immediately pop out at you. It's what turned this sort of dull (at least for a teenager) geoscience into a kind of puzzle where you have to figure out how to bring the signal up out of the data.


Replies

SoftTalkertoday at 9:01 PM

And, insects see flowers (and each other) differently than we do, as they are senstive to different parts of the spectrum, specfically ultraviolet. They see patterns and markings that are not discernable to human eyes.

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jacobolustoday at 7:29 PM

It's really fun to play with black and white photography using various kinds of color filters and see how different you can get the same scene to appear.

(Also fun to play with a polarizing filter.)

ambicaptertoday at 8:51 PM

> Ie. absorbing the reality that the way in which my eyes (or any optical sensor) see the world is not canonical. Vegetation is red, not green!

Pretty funny to figure out that your perspective wasn't objective reality and then immediately decide to canonicalize another arbitrary reality as the One True Reality.