C'est dommage que bon nombre de photos ...
{Instead of}: C'est dommage qu'un bon nombre de photos ...
I've always found it curious that the adjective "bon" tends to avoid being coupled with an indefinite article "un", most notably in the case of the phrase "(un) bon nombre de". Normally, I just put it down to an ironclad rule, but...
Ça a intérêt à être le bon bateau, cette fois.
{Instead of}: Ça a intérêt à être un bon bateau, cette fois.
... another instance has popped up where I cannot logically explain the presence of the definite article "le (bon bateau)" instead of "un (bon bateau)". This is the first time they talk about the boat in question, so I'd be tempted to say "it better be a good boat" rather than "it better be the good boat".