Black specks on kitty's tail?

So my cat has these black specks on his tail. I tried to pick them up, it doesn't seem like they can just be lifted off his skin but then again it's damn near impossible to get him to chill out just long enough for me to separate his tail fur to see his skin. His tail fur is really greasy and he has lots of huge chunks of dandruff. He has (had?) ringworm, it's still in the house, we're just in the process of getting it out of the house. He's not scratching at all, so I don't think he has fleas but it also doesn't look like ringworm at all. Even the other spots he had ringworm, there was no greasiness or dandruff.    Sorry the picture is unclear, he wouldn't let me get a good one. I'll try to get a better one later.

 

it kind of looks like flea dirt. 

If it's NOT flea dirt, and you can tell if it wipes off and is slightly reddish in color, it may be Stud Tail.  Stud Tail presents as black spots which don't wash off, along with a greasy area.  I think it's kind of like blackheads on people.  Here's a thread on it:  http://www.thecatsite.com/t/260709/stud-tail