Invisible crt getter?

[SwizzyMan]

So my Labor Day vacation turned into a TV hunt. I picked up a beautiful admiral with a 20B1 chassis and a phonograph. I didn't take my crt tester with me to Daytona where I am spending my Labor Day weekend. So I immediatly took out the crt to look at the getters. I don't see anything in the getter window all I can see is a rainbow like effect on the side of the getter window. This tube was a rebuilt 12LP4, could the tube still be under vacuum? Will start a restoration thread on this set once I get it back home and find out whether the crt is still under vacuum.