In January, landscape photographer John Mueller sparked a lengthy debate about the economics of art with a simple observation:

It cost me $6,612 to take this photo.

$12 in gas to go from work to this spot and then home. The camera I took this with cost $2500. The lens was another $1600. The Singh Ray Reverse Neutral Density filter was $210. The Lee Wide-Angle Adapter and Foundation kit was another $200. The Slik Tripod was another $130. The shutter-release was another $60. When I got home, I uploaded it to a computer that cost me $1200, and then I used Lightroom 3 which I got for $200. I then exported it and tinkered with it in Photoshop which costs about $500.

12+2500+1600+210+200+130+60+1200+200+500= $6,612

So if you’re a magazine, website, corporation, sports team, or advertiser who wishes to use this photo, please don’t come and ask to use it for free.

Mueller's essay hit two overly sensitive nerves. One was that of photographers weary of endless freebie requests, too frequently coming from considerably wealthier parties than themselves. The second nerve was that of people offended by overly simplistic economics. Obviously Mr. Mueller could sell more than the single photo from the same set of gear, so why is he griping?

Debate spilled from flickr across multiple sites. PetaPixel front-paged the piece, accumulated over 1200 comments, and a month later is still going.

Mueller's broader point, leaving aside the particulars of his calculations, is certainly correct. Being asked for free photo use is insulting if you make a living from photography.

Curious about how much I ought value my own images, I consulted my financial records. Here is what I consider a more realistic assessment of what an image might cost.

My direct photography costs average $6,000 a year. That sum includes travel to one international field site (at budget rates!), a couple big equipment purchases like lenses, and random small expenses like web hosting, gas, bank fees, batteries, and software.

My opportunity costs are higher: $45,000. What do I mean by opportunity costs? This year, for the first time, I am primarily self-employed as a photographer. I pay my mortgage, buy my groceries, and cover my bills from my photography income. 35k/year is what I made as a research postdoc at the university, and 10k/year is my previous annual photography income. The opportunity cost of transitioning to a full-time photographer is the amount I must make to recover my lost income. So, my total yearly expenses, as a full-time professional photographer, are $6,000 (direct costs) +$45,000 (wage) = $51,000.

Calculating my costs is the easy bit. Figuring out the dollar value of an image licence is considerably more nuanced.

I do not need to generate my entire photography income from image sales. In fact, I don't. I teach photography workshops and classes, give public talks, and blog here at Scientific American. Together, these activities amount to $9,000/year. Thus, to maintain an income that's somewhat lower than the U.S. median household, I need my image licensing agreements to pull in $42,000/year.

My insect image library currently holds 5,000 saleable photographs. I add 500-800 new images every year. To match my basic costs, I need each image to generate $8.40/year ($42,000/5,000 photos). That doesn't seem like much per image, but alas. The vast majority never sell. Most just wallflower away their time in the galleries. In practice I move perhaps 400 image licenses per year. A more reasonable approximation, then, of the worth of image use permission is $42,000/400 = $105.

$105 for permission to use one of my images is the average amount that keeps me clothed, fed, and housed enough to continue producing more images. $105 per photo is a bargain, too, considering that I have a Ph.D., a string of scientific publications, and my demographic peers are generally earning double what I do. I'm not complaining, mind you. I chose this because I love it, and I'm actually rather pleased that in the present economy I keep pace with my target.

Of course, at a more fundamental level images are worth the same as everything else: the price a buyer is willing to pay and the creator is willing to accept. I merely offer this post as an explanation for why the price I am willing to accept might not be "free".