This looks fantastic! Thanks for sharing.

From time to time I've looked around for good charts of the night sky, suitable for printing and browsing. These are the best I've found so far; they might be helpful to users of this program as a guide for how to design charts:

https://www.iau.org/public/themes/constellations/

Dude: not only great idea, well executed: practical, direct, to the point

What, exactly, are "constellation boundaries" good for? They seem to just be weird visual noise that doesn't really help with anything.

The night sky is big. These boundaries just help define an area of the sky that is easily communicated between other people. They help define physical locations. It's like discussing New York City, but then breaking that down into the boroughs Manhattan, Brooklyn, Queens, Staten Island, and Bronx. It just makes discussing a large area much more manageable. With constellation boundaries, you not only describe a physcial location in the sky, but potentially also a time of year (even night) as certain parts of the sky are only visible at certain times.

For a much more wordy read: http://www.ianridpath.com/boundaries.htm

I'm not sure I still see the value. The boundaries shown on modern maps are very strange and complicated shapes, and seem extremely arbitrary. Does it really help me in any way to know inside which convoluted an non-intuitive shape a star is?

I'm sorry the concept of boundaries being used to define specific areas are beyond you. Not sure how else I can help. If you look at the boundaries of any modern map of the geography of the earth, nothing is in straight lines. The borders of countries are very complicated shapes, yet you pretty much know if you are in a country or not. Cities are the same way, yet you probably know when you leave your city. Breaking into smaller neighborhoods it gets even more confusing, but yet again, you probably know when you're in your neighborhood or you're in the one next door. Knowing those boundaries comes from experience traveling around the areas. It'll happen the same way if you actually study astronomy versus just being obtuse about a subject on the internet.

How does my location factor into it? I usually have to set time and location on apps and sites and dont see any mention of lat/long here...

This isn't really creating a "what's in the sky right now" chart (which requires your location & time) so much as a map of the sky based on standard astronomical coordinates. These are the sorts of charts you'd see printed in sky atlases, for example, which don't have any relationship to your location or current time.

Ah I see. Thanks!

Might be useful with ITelescope as the parameter per telescope and time and location could be parameter.

Really cool, gonna give it a try tomorrow!