Decided to tilt shift my own shot of Andromeda.

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Tilt shifting space is easy and fun.

It's nothing new, or original, this was from 2015 (I don't doubt that there are much earlier examples): https://gizmodo.com/beautiful-tilt-shift-photos-turn-the-universe-into-prec-1684026109

With Andromeda, I think tilt shifting conveys a very misleading sense of the scene.

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When you tilt shift Andromeda, it looks like the galaxy is embedded in stars when actually, all the individual stars (in amateur images) are Milky Way stars. Here's a diagram where Andromeda represented by a stack of pancakes:








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We're looking out of the thin bit of our pancake (the Milky Way).

Imagining Andromeda was the Milky Way, we're looking out sort of like this.

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The Milky Way is pretty thin where we are, something like 1,000 light years. So when we're looking 'out' in that way we're looking through less than 1,000 light years of galaxy. Then there are very few stars until you reach Andromeda - 2.5 million light years away.

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You can see the stars of Andromeda, but you need a professional scope. Image - NASA/ESA: http://www.spacetelescope.org/images/opo1518a 

At least, I've never heard of an amateur achieving that. I think Mt Wilson 2.5m scope was the first to resolve them?

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Fairly random thought here, what would the sky look like if we were on top (or bottom) of the pancake? I wonder if it might make a particular direction of the night sky quite quiet in terms of stars . That would be weird. Thoughts like this keep me up at night.

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