Hi Image Analyst. I'm a student currently working on a project that involves detecting the presence of certain colors within images all taken under the same lighting conditions. I've been learning a lot from your Simple Hue Detection code, but am finding that I'm having trouble getting constant values for each color in different pictures (specifically dark brown, light brown, red, blue-grey, black and white). I've decided to use a color checker chart, but don't know how to fully use it to modify my images. Currently I'm using a modified method of the masks that you used for your yellow color detection that can successfully detect each color, but only for a narrow range of images. If you could, can you explain how I could use the color checker chart (a physical one) to modify the color in an image?