@SierraLatkje
If your using Gimp, you go to "Color>Channel Mixer...". Then in the new window, if the "Output channel" is red, change the "Red:" to 0 and the "Blue:" to 100. Then change the Output channel to blue and make "Red:" 100 and "Blue:" 0.
If your using Gimp, you go to "Color>Channel Mixer...". Then in the new window, if the "Output channel" is red, change the "Red:" to 0 and the "Blue:" to 100. Then change the Output channel to blue and make "Red:" 100 and "Blue:" 0.