23.01g Laureate head of Macrinus right "IMP CAES M OPEL SEV MACRINVS AVG" Securitas seated left holding a scepter "SECVRITAS TEMPORVM SC" RIC VI 205 It is not Alexander he those not use SECVRITAS TEMPORVM SC"
There you go, just click on the image and save it to your files. I think a solid background makes the coin pop out more.
The sharp and clear photo is fine in many ways but I see no reason to cut it so closely on all sides and certainly not clipping off the bottom. I would prefer the right facing obverse photographed with light coming from the top/right for better modelling on the face but the left facing reverse is fine as it is.
Hmmm, I actually kinda like your cool-gray background (it's a cool style => a style you could call your own!!) Oh, but I totally agree with Doug that you should back-up a bit and show the entire coin (great coin by the way ... congrats)