Barnard 252 is a 'Dark' nebula in the constellation Scorpius.
It is actually dark clouds of dust that block the light from the dense starfield behind it appearing to us as a swimming Dolphin.

A wider image can be seen here:

https://pbase.com/tango33/image/158698168

This is a simple RGB combination:
RGB - 10 min each
Total of 30 min

Telescope: ASA600 24" RC with Reducer at f4.5
Mount: ASA DDM200 Direct Drive with Absolute Encoders
Camera: Moravian G3 61000 pro