"You may lose 1 Imperial reputation to test Tech. If you pass, lose 1 fame to buy the top card of the ship market deck for free."

How does this work if you have the Tech ability? Can you choose NOT to test with Tech and therefore NOT lose the 1 Imperial reputation? Seems like you can since it says "may", but thought I'd ask.

If a card says “may” then it’s optional, so you are correct.

It also bears noting that you could still do this action even if you do not have the Tech skill (in which case, you would just roll as if you are unskilled).

If you chose to not test tech, you don’t get the ship. So it really depends on do you want the free ship or not.