Which platform is best for showing artwork: Instagram, Facebook, Twitter or LinkedIn?

Currently I am using Instagram, Facebook, Twitter and LinkedIn to show the artwork available in the gallery.

I'm getting more general response from Instagram but am getting existing client response from Facebook. I use Hootsuite to post to all and am very happy with that program.

 

Of course Artsy or 1st Dibs are great sales platforms and we use those. 

Any ideas of how to better use these platforms is appreciated!