Looking for help to clarify the structure of a sentence

Question

I'm preparing for the GRE test and there's a sentence that really puzzles me.

Marion Palfi's photographs would have received greater recognition from historians had her work been done in an era when most aspects of photography were static rather than in a state of transition.

Can anyone help me to make clear which word or component does had her work been done modify? And, because the sentence already has a verb receive, I'm not sure if had in the same phrase is a verb or a past participle.

Answer 1

'had something been done' kind of a structure is used to say 'if' it had been done. In other words, using 'had' in such context introduces the imaginary condition.

For instance, I'm not an expert in fixing a flat tire. But, I fixed it somehow. Since it's not fixed properly, you can say...

Had it been done by some professional, it'd ....

Check an example mentioned in Cambridge Dictionary

Had I known (= if I had known), I would have come home sooner.