Thermometer Question for Pro's

[BurntFingers]

I use two visual measures. When the firebricks turn white that indicates to me that they have reached at least 1000 degrees F. I keep the fire going if it its to be for pizza and check the hearth by throwing either flour or semolina in and see how fast it turns tan, brown, or black. That gives me an idea if the floor is hot enough for pizza. Bread is another issue. Let the heat sink in to the masonry so it can give it back later. Sometimes I use and infrared heat gun to check the wall temps but it is just for a general idea. I also experiment with location in the oven as the hearth floor is big enough to have different temps for different items.