I'll be honest, I hadn't even really looked at the people in the photo. I'd selected a photo where we didn't all look bored. Other than that the choice of photo had been selected because it had someone in it who hadn't liked having their photo taken and I wanted him to see it was worth it.
It really stung and my first reaction was anger. Even as I told the office, in a shocked voice I was internally grumbling. But the response from the office was to trivialise the issue and I think it snapped me out of it a bit. Yes, women were present, organising it. There were also female attendees from both academia and industry, but not at 50% representation.
I'm lucky to be in a team where women are represented well. I don't need to worry about my presence felt. The other bits of the university, the people I'm talking to, do have that imbalance. I should be more aware of that. It is a responsibility of my position. The comment I made about not paying attention their faces as I selected the photo a exactly the thing, when used as an excuse, drives me up the wall.
So hopefully I've dealt with it okay and it's not something I'll repeat. I fairly tame learning experience all in all.