Sony 100-400mm or Sony 200-600mm ?

[UberStar]

Hi all

 

Firstly i hope i am in the right section

 

I have recently go into astrophotography after watching many videos i have been inspired to get a zoom lens to get some DSO images of nebula and galaxy

 

I have purchased the 100-400 sony GM and am quite happy with it but now wondering if i made the right choice. I do have a timeframe that i can do an exchange for the 200-600mm and was wondering if anyone had experience with either of these lenses and what one would benefit me more ?

 

Personally i am thinking of echanging it for thr 200-600mm but not sure if that has any issues with CA and such ? Giving that its £400 cheaper than what the 100-400 is i am thinking it would be a bettr move then i would have that extra reach ?

 

I dont travel much and so the weight and size is not an issue for me alt all.

 

I would appreciate any opinions

 

Paul.