The 'California Nebula' (NGC 1499), named so because it resembles the California Peninsula in the U.S., is an emission nebula in the constellation of Perseus.
Radiation from nearby stars (such as 'Xi Persei' on the top right) ionizes this huge cosmic cloud of hydrogen gas, which re-emits this radiation and glows in red colour.
It's around 100 light-years long and is located in the Orion Arm, around 1500 light-years away from us.
This is a combined 7.5 hours of imaging in Hydrogen-alpha and 4.5 hours of colour data.
Full resolution image: https://www.astrobin.com/60r91f/C/
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Total imaging time: 12 hours (90x300" in H-alpha + 90x180" in colour)
Telescope: Sky-Watcher Evostar ED80 Black Diamond
Camera: ZWO ASI294MC Pro
Mount: Celestron AVX