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The Moon Is Transparent (Not!)

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You've probably looked up and seen this same sight once in a while with your own eyes: It may look like we can see through half of the moon to the color behind it as though the moon is transparent. Also notice that some of the darker craters seem to be the same color as the "background" on their south west edge in this photo. In the blue parts of the photos, my camera system and your eyes are seeing the same thing: the suns photons are scattered in our atmosphere and landing on your retina despite the sun not being directly in line of sight. Google this: "The result is that blue light is scattered into other directions almost 10 times as efficiently as red light." This is why the sky is blue. The light that takes the path from the sun to the moon to earth to us directly is much brighter than the scattered blue light we'd see anyways if the moon wasn't there so the camera just captures the sum of the blue sky and the moon.
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The Rule of 500

The rule of 500 is super old and predates high resolution sensors (like APS-C sensors). focus length in mm / 500 = exposure time in seconds Using the rule of 500, my Sony a6000 using an 85mm lens would mean I would see star trails if I kept the shutter open (aka the exposure) for longer than 5.8 seconds. And also a full frame A7 III the same would see the same even though its pixels are much larger. Obviously that is just wrong. If you just want to sanity check use the rule of 300: focus length in mm / 300 = exposure time in seconds This is a better rule of thumb these days. While there are apps that do this, I believe this is the actual source is:      https://sahavre.fr/wp/regle-npf-rule/ And you can maybe understand this better translated to English:      https://translate.google.com/translate?sl=auto&tl=en&u=https://sahavre.fr/wp/regle-npf-rule/ The true rule of 500 is actually from our guy down under: https://www.youtube.com/watch?v=q_Hxkex87jY
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Astro "photography" vs. Astronomy

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I believe there is probably a pretty easy definition between these two styles. In the photography sense, you want to tell a terrestrial story. Typically this is going to mean interesting  foreground subjects (trees, etc.) to go along with the amazing backdrop of our sky, often being the Milky Way or the Northern Lights. Even if you can't get those amazing subjects into frame, there is still much that can be said about our planet at night. Take Tahoe, August 2019 In the "deep space" kind of astrophotography, the goal switches to telling a story about the sky itself. A photo of the sky is produced by interactions from photos near and far, some being being emitted from an electron changing orbitals from as long as 13 billion years ago and fought all odds to get here. For that, you really need to look at the Hubble Deep Field to appreciate it. But your typical backyard astronomer, might focus on something closer, so maybe those photons are as little as 7,000 years ago (the Or
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Hello

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 I first got into astrophotography after a trip to Chile to see a total solar eclipse on July 2, 2019. I had two Sony mirrorless cameras, some lenses, some improvised solar filters, and lots of enthusiasms for that event. The funny thing is my eclipse photos were really bad. My brother's friend had a better lens (I think a 400mm Canon lens) and far more skill and got better photos of the eclipse than I did. His photos literally looked better than the photos being published on major USA news sites. One thing I loved is that he also stuck his iPhone in the sand and also got a fun time lapse of the event. The moon and the sun set the same time that day and we had a nice steak and then did something amazing - (maybe the next day) - we drove about an hour into the Atacama desert and pulled over in a random spot. That is when I got hooked into astrophotography. Milky Way, July 2019, A7R3, Samyang 12mm F2  When I got out of the car and looked up into a Bortle class 1 sky where the Milky W
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