Ken,
Please seek the permission of the photographer before downloading and using anything from The Gauge. You may reach most members by:
1) Posting a response in the thread where you found the picture.
2) Clicking their user name (on the left) and seeing if they'll accept an email and/or Private Message (PM).
In most cases, especially with photos that are uploaded to The Gauge, the size and resolution of the picture will not be adequate for your needs. Linked photos can be any size, but still may not be large enough.
If you are just using them for inspiration though, I think most would be flattered!
MasonJar thanks for your response. If I find a photo that I would like to do as a backdrop I would ask permission. The photo would only be used as a visual image for me to supersize by airbrush to my backdrop of 6'H x 14'L