For this, within your research you have to figure out who the audience is for the images you're looking at. For the most part you're encouraged to look at 'Personal work' as opposed to the photographers commissioned work, reason being, the wider photographic community is far more interested in personal projects undertaken by the photographer than their day to day commissions. As part of the making sense of the audience you're going to have to identify how you think the images are intended to be used and what their purpose is? You'll have to research or speculate initially, how you think the work will be presented and in what format - exhibition, book, touring show, limited private sales, auction houses etc. This will give you some sense of who the target market is.
If you dig a little deeper... Try typing your photographers name in Google and adding 'Sold at Auction' you'll get an insight into how much the individual prints or books cost. Look up Peter Beards limited edition book at Taschen - who do think the Audience is for his work - who is his buying public? Would you expect to see his books being sold in WH Smiths in the high street?
Different photographers have different approaches to marketing themselves, dependent on the message within their work, so for some there will be a balance that's needed to be struck between addressing and accessing your audience in order that you get the message out there. What's the point of having something to say through your photography if it's only ever going to be known within an exclusive group of people?
So, when you're researching - get a feel for who is going to be interested in the images and themes you're highlighting. In the same way that you make sense of people's socio-economic status in the images - think too about the people that buy and access the photography... Who are they? Rich, poor, educated, Guardian readers, Daily Mail readers, amateur photographers, young, old, black, white, female, students or professionals?
One of Art's greatest challenges is to make Art more accessible to a wider public and not just to the educated middle classed. So with this in mind - look at your photographer, look at the message, meaning, theme and content and ask and explain how it addresses these differences if it does at all?