There are a decent number of stories going around the Internet about how artists should push back on being asked to work for free. Let me state up front that I agree with this position to the tune of about 80%.
There are times when working for free makes sense - if you're doing a favor for a friend, for example, or you're donating your time to a good cause. I've done some artistic work as a gift and I know some photographers who regularly shoot weddings as gifts (and that's an expensive gift!). I've shot bands that I love in exchange for being let into the venue for free and the necessary front-row stage-side access. I can be a fanboy like the next guy. This isn't about those times. This is about the times when someone who can and should pay for your artistic talent and time still asks that you do/perform their gig for free.
This article, http://revolva.net/2014/11/13/an-open-letter-to-oprah/ describes how Oprah Winfrey asked an artist to attend and perform for no compensation (and, after pushing back on the issue, offered a little gas money before revoking the offer completely). The artist rightly points out that while "exposure" was dangled as the draw, her landlord won't accept rent payments in whatever quanta "exposure" uses for measurement. I'll stop using quotes around exposure now.
That outlined, I have found a sure-fire, ultimate counter whenever someone promises you exposure in exchange for your time, work and talent. The conversation goes something like this:
Promoter: Hey, Chris, I have this fantastic project I'm working on, and I need a photographer. I immediately thought of you because I love your work. You'd be perfect for this gig!
Photographer: Wow, thanks, I appreciate that! Let me read over these requirements... okay, yeah, that's a lot, but I can nail this for you. Let's talk fee and usage - what's your budget for this, and let me see if I can exceed your expectations.
Promoter: Well, there's the thing. The budget is zero for photography. We're spending a lot on everything else, and, well, we're just out of money. But look there are going to be hundreds of people there and they'll all see your work. You'll get tons of exposure out of this that should bring you lots of paid gigs.
Photographer: Oh, really? Well, hey, you know your stuff, right? You're pretty confident about this?
Promoter: Absolutely. 100% certain.
Photographer: Well, not to get stars in my eyes, but let me outline this. My normal fee for something like this would be on the order of $2000. If I do this for you for free, that's $2000 I'm not getting. But you say hundreds of people. Do you think I could get three paid gigs out of this?
Promoter: Easy. Do a good job and sure, I could see three people hiring you based on your work. Maybe even five!
Photographer: Let's say three, just to be fair. That means by giving up $2,000, I could make $6,000. That would be a profit of $4,000. That's not bad.
Promoter: Now you get it! I'm totally jazzed, man!
Photographer: Great! So here's my proposal - since you're so sure that I'm going to make this money, I want to cut you in. You pay me my normal fee of $2,000. In exchange, I'm going to split everything I book from this gig with you, 50/50 as a thank-you for giving me such an incredible opportunity. If I book three gigs, that means that you paid me $2,000, but I immediately turn around and give you $3,000 back. You actually make $1000 just for hiring me! And if I book five gigs like you said, that's $10,000 in bookings. You get $5,000, minus the $2,000 you already paid me, meaning you profit to the tune of $3,000 on this deal. The sky's the limit, my friend! Exposure!
And that, my friends, is how you use math, science and common sense to take down the myth of exposure.
If you ever do this and it works, I'd really love to hear about it - share in the comments, any time. And feel free to share and repost this advice. It's free (as in beer) and I hope it helps someone spread the message.
PS: Any aspiring web comic who would like to take this conversation to a set of panels, get in touch. I'll trade the text for the art and we can both publish it. That's not exposure, that's barter, if both parties believe they're getting value. See how easy that part is?