For SEO And More Traffic Add description to each photo. I.E create a separate page for each photo or group of photos. Write description, use some keyword so that you can derive more traffic by having multiple pages.

You should add PinIt or social sharing button. Its not Good to giveaway image on single click. People will have to reupload that image to share in their social network and more importantly you won't get credit. So why not allow a single click sharing option? And give you website more exposure to social networks as when people will share through your URL you will get high traffic in response.