Originally Posted by gto_ron
I watched the video twice. If I used that technique I'd have runs everywhere. Notice he's in a professional quality paint booth, there is no fogging at all.
I don't understand why the door wasn't masked off when he shot the quarter panel.
Because you want the SAME amount of paint on the blend panel if you can. This is one mistake a lot of painters I have seen make. They mask it off, then paint the quarter then unmask it and blend. There isn't enough paint on the blend panel to cover the original paint and the blend was a waste because it doesn't match the quarter! Sure you CAN do it if you blend properly. People will think "well the color is almost exactly the same so it will cover fast", but this is simply not the case. It will cover faster, but wifing a little paint over the original paint as a blend often isn't enough.