Hey all. I've done a lot of TIG welding in the past but I've always wondered how some of these guys get the shiney rainbow colored welds on stainless. My welds are usually grey and dull looking.

I hear from talking to others that I'm welding too hot and basically cooking the welds too much. I've tried welding cooler and moving faster but I still can't get these kinds of results. Will back purging make welds like this? Anything else I can try?