I recently mentioned this issue within another context. I personally have:
- Added robots.txt
- PHP code to capture desktop and notebook right click and key codes, CTRL+C, etc. to slow the process, similar to Amazon.
- Added watermarks with copywrite information to all images including thumbnails
- Control the resolution of published images with notation throughout that best quality images are for sale including virtually any format through FotoMoto. I also clearly note that the purchased images are of best available resolution and contain a discrete watermark.
As I discussed in a previous context, resolution of published images, which also impacts screen shots, is at present the main remining deterrent; however, AI driven software packages such as Topaz Gigapixel do a appraisingly good job of intercalating pixels.
In summary, I feel your pain and do not see an answer on the horizon. My layered approach helps honest visitors stay honest and I have accepted that there is little I can do for the rest if I still want to publish my work.
Regards,
James