I could be wrong here as I am new to tracking Astro photography. I believe that tracking a planet would need to be at a different tracking rate/speed as it is moving in an orbit plus rotation of the earth. To me it sounds like your star photos are really sharp which lead me to this idea. Also longer focal lengths un guided can be difficult.
Just starting in this Hobby, I have been doing wildlife and landscape photography.
Exos2-gt PMC-8, Celestron Alt/Azimuth
Celestron SLT 130, Olympus 7-14,12-40,40-150 Pro and a Canon FD 500L
Olymous om-d E-M1 Mkii,