Google+ versus Facebook for photographers

I don't promote my photography heavily or work hard on networking with other photographers, but I do post on social media sites and over time I've noticed a shift in how photo posts are received.

Take a fairly mediocre macro shot like this:

The original had some issues with the composition but it stood out from the rest of the set because of the escaping bubble which I quite liked. A crop, rotate and slight tint improved it sufficiently that I thought it would be ok to publish, so it went up on Facebook and G+. The results are shown below.

The reaction on Facebook

The feedback on G+

While the comment rate was similar, six times more +1's were received than Likes. While I do have about 40% more followers on G+ than I have friends on Facebook, this does not suffice to explain the difference in response. I do not use restrictive privacy settings.

The main differences I can think of are:

- G+ gives a nearly full screen view of the image, while Facebook reserves considerable horizontal width for the description, comments, etc. The image looks better on G+.

- Reaching the right audience for each post is easier on G+ using hash tags, circles and events than on Facebook. There seems to be a strong self-organizing photography community on G+.

- People seem to be losing interest in Facebook, especially since the much-maligned migration to the timeline. The accounts remain active but public participation (sharing, commenting and liking) seems to be dwindling.

The second point, reaching the right audience, strikes me as being most important here. For me there is no doubt that if I was only going to be posting about photography in one place, then it would be G+.