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Hello and thanks for your contribution! This is very interesting but can you please clarify on what science cases that have motivated you to implement this? Astronomers use log base 10 for the magnitude systems. Also, now that you have introduced a different base for the log, should astropy.units be able to translate between the bases (I cannot tell from the new tests you added)?

If we decide to proceed, this PR would also need:

• change log
• user facing doc, plus example
• what's new entry