Deconstructing Images

 I start with a nice input image of some flowers on my prickly pear cactus:

I then generate a "color-magnitude" diagram for some configurations:

The left two panels show R on the x-axis, and G-B on the y-axis.  The white line separating the two panels vertically represents a value of zero.  So pixels appearing above the white line have a positive G-B value, and those below the white line have a negative G-B value.  The middle two panels show G versus R-B.  The right panels show B versus R-G.  The colors of each pixel correspond to their colors in the input image.  The x-axis range is 0 to +255 (left to right).  The y-axis range is -255 to +255 (bottom to top).

Here's another example, using the image of the Earth taken by Artemis II:

Here's R vs G-B, G vs R-B, and B vs R-G

clearly picks out landmasses, ocean, clouds, and aurorae!

Sandhill Cranes Long Exposure

30 second long exposure of a flock of Sandhill cranes 'circling' over my location a couple days ago.  The cranes are here from mid-October to about March every year.  I'm situated right over their daily flight path as they visit various playas and other locations with standing water this time of year

I See The Murmurations

I see the murmurations of the black-birds

And stand there in awe of the numbers

I think about the effort it took

To get them all there

- CosmicLettuce

(text generated by me, image generated from Grok)

Magnetometer Bike Ride

A bike ride with the magnetometer on my phone recording at about 60Hz.  I've got x, y, z, and r axis data:

And here are the corresponding power spectra (spectrograms):

Bike Ride Spectrogram

This is a spectrogram of the accelerometer data collected on my smartphone as I ride my bike.  The y-axis is the time (it was about a 909 second -- 15m 9s -- ride) and goes from top to bottom.  The x-axis is the frequency (0 to about 100Hz) and goes from left to right.  Lots of interesting harmonics and other complex structures.  This is sampling every 100 measurements, or at about 2 Hz (once every 0.5 seconds):

The plot above is also the sum of the x, y, and z axes.  Here are the individual axes:

X:

Y:

Z:

Here's a plot of the z amplitudes (in g's) versus time (x-axis, seconds).  This is sampling about every 0.5 seconds.

Here's the same data, but just every data point with no skipping:

Here's another ride earlier that day, going the opposite way.  This is the x-axis g-force on the smartphone accelerometer:

Happy Mole Day!

Happy Happy Happy Mole Day!

This is my third favorite number!  Behind pi and e.

Dawn 22 October 2025

 My location: