Hi. I’ve been using a Canon T6S for a few years attached to a telescope. I decided to upgrade with a gently used 6D because of its low-light shooting ability. Around the same time, I was given a very nice 70D that was owned by my late grandmother. Both cameras have performed great. I will say that while the 6D is better by leaps in low light, I believe the 70D actually takes more crisp photos in daylight! Look forward to sharing my work, and seeing yours!
Hello and welcome to the forum Rodney. I am looking forward to your input to the forum. With the camera bodies you have, I think that just playing with both of them during daylight to find out which one works best for you. When the light level falls, the 6D should come into its own. Gary