I recently received an email from a photo researcher, on behalf of her client, a book publishing company, requesting use of one of my photos ("Numbat" - shown below) for inclusion in a college textbook.
The email included some details on how the image would be used (1/4 page), the size of the print run (40,000 copies), and the distribution of the book (US and Canada), and requested details of my reproduction rights for the photo, indicating that if they were approved, I could then submit an invoice.
As I've had similar requests in the past, I responded with details of the reproduction rights, as well as a price for the use of the requested photo.
The conditions I specified, including the price, were considered acceptable, the photo researcher then requested an invoice, payment was arranged, and I provided a high-resolution copy of the photo.
I suspect the photo researcher found my photo in my photo gallery while searching the internet for suitable photos.
Selling photos in this way can be as easy as described above. You just need to publish your photos on the web, either on any of the many photo-sharing websites, a social networking site, or in your own photo gallery on your website. Tagged each image with appropriate keywords, and an appropriate description, to ensure search engines will know the context of the photo, and can direct appropriate visitors to your photos.
It's important to point out that you need to make sure your contact details are easy to find, else a prospective buyer will not be able to contact you to purchase a photo!
When determining the value of a photo, you need to consider the following aspects:
- Intended Market - Markets include advertising, corporate, editorial, and others.
- Media Type - What type of media is the photo going to be used in? Will it be used in a magazine, book, newspaper, or website?
- Image Size - What size will the image be reproduced in the publication? Will it appear on the important front cover of book, will it be 1/4 page, or will it just be a small minor image?
- Distribution - How many copies of the publication will be produced? Will it be 10,000 or less, or possibly up to multiple millions of copies?
- Exclusive Use - Is exclusive use of a photo required (ie, you cannot re-sell it to anyone else), or will you still be able to re-sell the photo to any other clients? In most cases, explicitly specify that you're providing the photo for non-exclusive use.
I find the Stock Photo Price Calculator a useful reference for obtaining an indication of the value of a photo. It allows you to specify the type of market, type of publication, size, distribution, and it'll provide a low, average and high price based on the criteria specified.
There are a number of other websites that provide similar information, including the NUJ Freelance Fees Guide: Photography website. For a bigger-picture view, the NPPA Cost of Doing Business (CDB) Calculator can be useful, as well as the this discussion thread on flickr.

There are a lot of things that need to be considered and agreed on when arranging the sale of a photo, and here's some of the key things to consider:
- Reproduction Rights - Provide a comprehensive, non-ambiguous list of reproduction rights to the prospective buyer, and ensure they agree to adhere to these rights. This includes specifying how the client is allowed to use the image, whether you retain copyright on the image, any restrictions of use, whether a credit needs to be included with any use of the image, whether the image can be modified, etc.
- Price - You need to agree on a price with the prospective client, and this may include some negotiation, depending on the client's budget.
- Payment Method - You'll need to agree on a method of payment, and make sure that you're aware of any hidden costs, such as international transfer fees, cheque handling fees, etc. For example, in Australia, it can be an expensive exercise to bank foreign cheques (~AUD$50 per USD$ cheque!).
- Delivery of Photo - Once payment has been made, how are you going to provide a copy of the requested photo to the client? Can it be emailed? Does your mailserver and the client's mailserver allow attachments of that size? Alternatively, can you make it available on your webhost or elsewhere?
- Legalities - If the photo includes any recognisable people, then a model release form may be required, depending on how the photo will be used, and on the local laws of your country and/or the country where the photo will be used.
- Copyright - Make sure that you specify that you retain the copyright on the photo.
While selling photos in an ad-hoc fashion like this is unlikely to make you a fortune, it can provide a mechanism to get some income from what can be an expensive hobby.
Thanks for the very informative post! What kind of megapixel count and file format and such is preferred for this kind of thing?