Vartilcal white line on magenta color - Canon imageRUNNER C3220 Color Copier

Some enlargers have dials on the front that are labeled yellow, cyan and magenta. These enlargers are made to print both black and white and color photos. To print in colors you use the dials to perfect the colors of your print. Let say that you took a picture and the colors look to be a bit off. In the light you would hold up a color filter to the image and decide which filter makes the color look closest to what you want the final image to look like. Then taking the information on the card you go back into the dark room and adjust the dials on the enlarger according to the card that was used. If you were looking through a green filter then you would lower the number on the magenta dial.

Printing in black and white on an enlarger with these dials is a little different. Since there are no colors in the black and white paper these dials have a different function. They are used to adjust the contrast of an image. If you turn the light on in the enlarger without paper under it and turn the dials you will notice that the magenta will make the light darker. When you print with the yellow and cyan dials at 0 and magenta at around 10-20 this will add contrast the image. You can always develop all your negatives without touching any of these dials, but if you can master them then your images will have a little less flat than those with little to no contrast.