One physicist used to greet me: "Ah - the one doing research into ice-cream" with a slightly disparaging air. Through gritted teeth, I would explain again that my PhD was actually in polymer physics. The problem was, I gave talks to the public on "the physics of ice-cream".
The subtext was clear. I was less credible because I spent time engaging with the public - "dumbing down". Just how many more papers than his students did I need to publish for him to take my research seriously?
Academics sometimes feel they can criticise colleagues who talk with the public or the media. Countless scientists feel it's bad for their career.
Clearly, spending too long away from the lab reduces your publication rate.
But even short forays can be damaging: simply appearing in the media can elicit fellow academics' wrath.
Strangely, everyone claims that engaging with the public is good. Most universities, research councils and charities have mission statements requiring it: sharing knowledge and making a contribution to society. The Government's Office of Science and Technology encourages academics to engage with the public in many statements and reports.
So why the criticism? I think some scientists see aspects of engagement as "trivialising". We hear that phrase "dumbing down" so often. But why make things hard? What's wrong with making a subject appeal to people?
When we enjoy a poem, perhaps the rhythm or imagery appeals, or evocative words take us back to a distant memory, sending shivers down our spine. Or we may enjoy the humour or the insight. A literary critic may understand nuances some of us will never fathom, but the rest of us aren't barred from enjoying poetry.
Why can't it be like that with science? Why not delight in people enjoying an idea, or a scientist's life story or a book? Why deride small offerings? If some people want more, they can get it from the New Scientist , the BBC's Horizon programmes or even scientific papers. Maybe if others enjoy the small "appetisers", they'll be tempted to find out more. Or maybe not - and surely that's fine, too. Science is a part of our culture, so why impose on others how they should enjoy it?
Most of us get our information about science from the media. So isn't it crazy to leave it to others to talk with the media about science without involving the very people who understand science best?
Scientists can also be unwilling to talk about the ethics surrounding science - scientists are supposed to deal with the science, not the way others choose to use it. But ethics is often just what the public want to discuss. During my entire education in physics, I didn't once have to consider ethical issues. It was thought irrelevant. But if scientists refuse to speak with the public about issues that might affect every one of us, they are acting as if they are almost beyond values. How can the public trust such people?
And sometimes scientists are inclined to envy. It's not easy to see someone else getting attention if we feel our work is just as good.
So if we want to share the beauty and culture of science; if we want young people to continue to study science; if we want the public to fund science and to use it to make responsible decisions about their lives; and if we want policymakers to understand science and technology well enough to make wise choices, let's stop criticising and value the scientists who talk with the public. Science's future may depend on them.
Kathy Sykes will speak at the Cheltenham Festival of Science, June 8-12.
For further details, visit www.cheltenhamfestivals.co.uk/
Kathy Sykes Collier chairwoman in public engagement in science and engineering, Bristol University, and director of the Cheltenham Festival