Friday, September 29, 2017 found us at anchor off Rábida, the smallest island on our itinerary. It is known for its red sand beaches. We started with a nature walk. There were starfish washed up on shore:
Starfish
Pretty morning glories:
Morning Glory
Quite a few lava lizards:
Lava Lizard
Lava Lizard
And we got our best look at the Galápagos Flycatcher:
Galápagos Flycatcher
Galápagos Flycatcher
Galápagos Flycatcher
Galápagos Flycatcher
Galápagos Flycatcher
We made our way to the top of a hill where we took a group portrait:
I got two GoPro Hero3 Black cameras and am planning a panoramic project with them. However, to do the project correctly and accurately, I need a good read on their field-of-view. So, I set up a tripod and a grid and a tape measure, and took a few photos. Here they are, desaturated and contrast-enhanced, with central red dots and some annotations. First, measuring the diagonal FOV: Next, the horizontal FOV: Finally, the vertical FOV: The front of the camera lens was almost exactly 17 inches from the grid. The camera body started about 17.25 inches from the grid. Assuming the sensor is embedded some distance into the body, I used an estimated field-to-sensor distance of 17.5 inches. This yields the following field-of-view, in degrees: Diagonal: 146 Horizontal: 121 Vertical: 93 Doing a little interval math on the field-to-sensor distance shows these angles are accurate to about plus or minus 1.5 degrees. Int...
I got up this morning very early to make an animation of Jupiter, Mars, Saturn, the Moon, Venus, and Mercury as they rose in the early morning sky. Here is the finished product: It was very cold - 7 degrees Fahrenheight - and very early. This is a 30-minute sequence starting at 5:39 AM and finishing at 6:09 AM. All of the images have the same parameters: Canon 7DmkII camera Canon 8-15mm f/4L lens, locked at 10mm (widest useful zoom with this lens on a 1.6x crop camera) 8 second exposures at ISO 3200 Image sequencing performed by Canon's EOS Utility. A capture was started every 15 seconds. That camera/lens combo yields a 180-degree diagonal field-of-view. Jupiter and Mercury are about 120 degrees apart in these images, so this gives some extra room for animation and cropping. Capturing all five planets in the pre-dawn skyglow is surprisingly tricky, especially when city light pollution is contributing to a murky lower atmosphere. ...
A few years ago, I converted various planet maps to icosahedral models . You can print these out, cut along the solid lines, fold along the dotted lines, and have a nice icosahedron to play with. Since then, two more robot spacecraft have created global maps of planetary bodies. Most recently, the New Horizons spacecraft flew past Pluto. Here is an icosahedral projection of the data we have so far: Also fairly recently, the Dawn spacecraft has orbited both Vesta and Ceres, two of the largest asteroids (or "dwarf planets" as the new nomenclature has it) in the Solar System. Here are icosahedral projections of those two. First, Vesta: Next, Ceres - note the mysterious white spots toward the upper right: All of the data used to create these projections was taken from Steve Albers' Planetary Maps Page , which I highly recommend. Edit: A PDF file of helpful hints on assembling these can be found here .
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