The OGMA AP26CC and AP26MC models are very similar; their main difference is that the AP26CC uses a color sensor while the AP26MC uses a monochrome sensor.
You can read these two model numbers as follows:
AP = Main use, in this case Astrophotography
26 = Number of megapixels, in this case 26Megapixels
M or C = Indicates whether the camera sensor is Monochrome or Color
C = The last character indicates whether the camera sensor is cooled or not
