 of the, how do you measure the light, the different colors of light for different sources and different filters and stuff like that. So, in the previous case, I showed you how to get these two pictures. This top picture right here, this is a picture from that same device I showed, oops, don't zoom in please, oops, okay. And this is just looking at the floor and the hallway in the building. And this is looking at the ground outside, okay, so you can see that they are different, they're definitely different brightnesses and stuff like that. So let's just go ahead and how do you analyze this. So this is tracker video, if you're not familiar with that, a lot of people associate with analyzing, doing video analysis for movies, but it does a whole bunch more. So I have, I've already put the picture in here, one of the nice things is, if you want to compare, you want the image sizes to be the same and so that everything lines up. Because really I'm measuring the different colors at different distances and if I want to associate a distance with the color, then they need to be scaled the same. And so you want your camera set up the same way for both of the things. It might be best just to use a tripod and not even move the camera or the diffraction grading so that none of these things change. And then you'll, you can issue the exact same picture and they should not be lined up automatically. Okay, so what you're going to do here is go to create a line profile. I forgot what it was, so, okay, and oops, zoom back in. And so here's the line profile thing. You just do what you normally do, you, you're going to draw a line over the region you want to analyze. So I'm going to start from like right at the edge of this and go that way. So I'm going to hold down the shift key. I'm going to click and then I'm going to click over here. Oops, I'm sorry, I'm an idiot. I always forget these things. Okay, let's just, let's just delete that. Okay, create line profile. I'm going to shift drag, you got to drag it. Okay, let me go as far as I want right there. And you see over here what it does is it produces, looks along this line and the different brightness of the different colors right here. So you can see this looks like this color is maybe green, green and red right there I suspect or maybe blue. And then there's some other colors out there too. Okay, now let's go ahead and look at the same thing over here. Create line profile and do the same thing. And there you can see that it's different. This actually, why does this go up like that? This is because my boxy insides white and the light was so bright that was reflecting up the walls. This was a poor choice of lights, okay. And then these things right here are that stuff. So really I'm looking at that. And you see here that I actually get the colors twice, same thing here. So that depends on your fraction grading about how much it bends the light. You're going to get this whole thing repeating. But you can make a comparison between these two. If I want to just look at this and go to analyze, I can look at it in a little more detail and I can see what's going on there. They also, so you can plot just the red, I don't know how it does that. Just the green, just the blue, Lumina, that's what I had before. This is by pixels. Now, this is not, this is not the wavelength on this horizontal axis until you somehow calibrated. So if I know the wavelength of this color and that color then I could, you could set the origin. What I've done is put the origin right here and then go over here to set the scale new calibration stick, actually the origin is going to be really far away. And then you can say, okay, that's 100, you can set this whatever you want to be and say that's however many wavelengths, whatever units you want. And then it'll look better. Or you can just export the data and then rescale it in a spreadsheet or whatever like that. But the other, the cool things to look at are, you know, how do different cameras see the same light? The sensors are different. So you're going to get different things. But okay, that's a quick introduction to how to use video analysis to look at light. I don't think these were the best examples, but there you go.