We have now finished and bug-fixed the "Sales option 2" that was mentioned a long time ago. Everything has been rewritten, and those of you participating in it a long time ago might see that the old instructions does not work anymore.
In short this means that everyone that ever uploaded a photo now can log in to your "myphotos" Photographer's corner and there choose to create an FTP account. You will then be able to upload a whole batch of images with higher resolution than the normal "large" version available on the site.
The purpose of the high resolution large images is that it will be possible to order larger printouts through PhotoBox. I'm not sure about the revenue, but I think you earn more per photo if you sell large printouts compared to the normal smaller ones.
Check it out by logging in to http://www.airliners.net/myphotos/ and clicking "Large prints". Read the instructions carefully.
Please note that special characters such as / and & in your username or password might give errors when creating the ftp account. Please report this to me directly if it happens to you.
P.S. A current forum username is needed, since it's still in beta-testing phase. We are working hard to make it available for all our photographers as soon as possible.