T Too many people put up images on their website and do not take advantage of Image SEO. It is pretty typical when I look at a site that I see that the image is named image 123456 or some such thing and that does nothing at all to aid you in the process of getting your site ranked or of getting your images ranked.
Both the image and the nomenclature attached to the image are important.
There are several places where you can take advantage of some pretty easy on-site SEO with a little bit of work and, odds are, the competition in your niche is not taking advantage of this so you'll get an immediate leg up on them in Google's eyes when the bots crawl the site and see your site in their little bot eyes.
The easy one to hit on in this process is the caption. Your caption can be your main keyword or a very small variation of the keyword to identify what you are sharing with the reader. I almost always just use the main keyword as the caption as I am stressing that point to the visitor that actually reads it.
There is a place to give your image an alternative name called "alternative text". This is where I will either use a synonym or even go and use a longer tailed keyword. Do not give it the same name as your caption as that is wasting the opportunity to get more keywords in front of the bots face and thus missing out on some free easy SEO.
Nest place to consider when using images on your site for SEO is the description. Here you can really ride the wild stallion and add in 150 - 200 words about the image. I come real close to keyword stuffing here and, although what I put makes sense, I am it worried about it being Pulitzer prize material. I want to give the bots something to consider and take back to Google central so they say, "Hey, the guy from yPick.me has a pretty strong site, let's rank it!" so there is some meat in that part of the image backend.
Not much to it, Folks, but I do believe and have seen, this be an aspect of SEO that many people need to address and fail to do so. Image SEO could be a game changer if you are in a close race with the other guy that is trying to rank for the same things as you so take five minutes of your life and use it to your advantage.