MICHAEL COOPER So what is the mix that those who cast operas should be looking for? Is great singing, by itself, enough? How much acting ability is needed? How much beauty?

I have fond memories of attending some operas that were, truth be told, little more than concert versions that happened to be given in costume, on sets — even if that is far from the ideal. (By the time I got to hear Montserrat Caballé, in “Tosca,” she was not up to leaping off the Castel Sant’Angelo, but she left me with a lasting memory.) But I wonder if performances that once worked through opera glasses still work in an HD era — when opera Grammy Awards are won by DVDs, not CDs, and many people turn to YouTube to listen to music. Will younger audiences learn to thrill to great singing, even from figures less than ideal, as some of us did?

TOMMASINI Well, this is a complicated matter.

Great singing alone, if it’s really great, is pretty, well, great. But most of the time, in my experience, great singers also have at least a compelling presence onstage. If not, that can be a problem. But it may well be worth it to experience a singer who vocally and temperamentally owns a role, but may be a little bland as a stage presence.

But audiences play a role in this, too. We have to accept artists for what they are, what they offer, not for what they lack and what they may not look like. And the arrival of HD broadcasts certainly raised expectations, no question about it. When Karita Mattila sang the title role in Jürgen Flimm’s modern-dress production of Strauss’s “Salome” in 2004, she was astonishing. I have never heard the role sung more thrillingly, dangerously. And she looked amazing onstage — seductive, possessed and sexy. Her “Dance of the Seven Veils” culminated, all who saw it will remember, with a brief flash of frontal nudity. Could a performance have been more courageous?

But in the television broadcast, in close-up, Ms. Mattila, though beautiful and striking, looked glamorous but clearly middle-aged. I didn’t care, of course. But some directors, opera fans and, alas, company managers may care.

About pulling young newcomers into opera, I trust in the power of the art form. But young people must somehow get themselves into the opera house to hear it live, with natural sound. At a social gathering recently, I was talking with a woman who was unimpressed with the tenor Javier Camarena as the prince in Rossini’s “La Cenerentola” at the Met. She thought he looked not princely at all. To me, Mr. Camarena is a perfectly nice-looking man, with maybe just a touch of a belly, but an actor with an appealing stage presence and lots of communicative energy. And what a fabulous, exciting singer! If you don’t get this about Javier Camarena, then you are just not part of the target audience for opera.