Selling images online: Choosing a stock photo agency
The first agency where I started uploading my photos was iStock (because it was the only one I knew at that moment :) Now I am glad that it happened that way because they are strict with image quality, and they explain all their rejection reasons, so I learned quite a lot just by correcting and reuploading photos that were rejected.Dreamstime, Fotolia, BigStockPhoto, StockXpert, and 123rf.com are good to start too.
Shutterstock is definitely the site you will want to join but it can be much more difficult to get approved than on all other sites. You will need to submit 10 photos for review, and have 7 of them approved. If you are not accepted, you can try again in a month. Shutterstock alone can give you about 50% of your total earnings from microstock, so it's really worth trying!
As for new agencies which still have very few sales, photographers' opinions vary. Some consider it a waste of time because images don't sell, some see it as an investment for the future. It always takes time before a new agency starts selling well, and they usually start marketing only when they have at least 200,000 photos in the library.
For myself I decided to invest my time in those new agencies which have good uploading system, comfortable navigation and fast approval process. The examples of these are ImageCatalog, which seems to combine all the best features of already existing microstock sites, and Albumo, which pays you for uploading your images. Another two up and coming sites are Scandinavian ScanStockPhoto and StockPhotoMedia. They have been very slow in the beginning, but it seems like finally things are starting to change, and sales get more frequent. They pay in euros, and StockPhotoMedia sends a payout every 3 months even if you haven't reached your minimum payout limit. These sites may be appealing for beginning photographers because they usually accept photos much easier than big photo agencies who already have huge collections.
Here you will find a complete list of stock photo sites.



