Not so unsual actually..... I captured pictures of some old slaves and an angel in a picture I took in 1978 in Jamaica on the Rosehall plantation, and when we sprinkled my husbands ashes at Lake Powell I took pictures from the top of the houseboat of a friend who went and months later when I finally downloaded the pictures there in the picture was my husband -- I knew he was along for one last trip that week, but I was still surprised when I saw him in the photo....
There has been a lot of cases of people taking pictures in cemeteries and getting spirits in their pictures, sometime just an orb and sometimes a partial body and sometimes a full body like this picture you posted...
That's a pretty cool story. I myself try to maintain a healthy skepticism. I've been a photographer for over 40 years, and have seen a great number of purported "ghost" pictures over the years. Some turned out to be outright frauds, while a significant number of others might well be explained by light anomalies (both reflection and refraction), multiple exposures, etc.
But there are also a fair number that do not yield to logical explanation. I have taken a couple of these myself. As an example, I was out photographing autumn leaves very early one October morning and came upon an old barn in a state of disrepair. The building, as lit by the rising sun and framed by the autumn leaves made for some nicely composed shots, so I began to take pictures of the barn, including its glassless windows. At the time, I recalled the distinct feeling of being watched, even though there was no one around or awake in that remote spot at 6:30am on Sunday morning.
I returned home, had breakfast, and then uploaded the pictures to my computer. In one of the barn photos, I thought I saw something in one of the windows, so I zoomed in and increased the gamma value... only to see a ghostly image of a woman's face peering out through one of the windows on the upper floor of the barn. It definitely spooked me.
Now here's the kicker: I went back the next week to take a look around and see what, if anything, might have caused the image to appear. I poked around the barn and was able to get a good look inside through a partially-open doorway. And that's when I saw something that sent a chill down my spine: the old barn not only had no glass in its windows: the floor that would have rested beneath the upstairs window... was gone.