Definitely but not very easy! Do you have a photo of him at a similar angle preferably in the same tack and ideally but not necessarily jumping (doesn't have to be exactly same scale as I can tweak that), and two or 3 of him just jumping? They don't have to be the same scale or even the same angle just want them for reference so I get what he is doing with his legs, then I can have a play.
If you pm the links I will have photoshop on the laptop for some real work at some point this evening, so a distraction will be welcome! Might take a day or two of playing with though, I am not an expert just like to play with Photoshop!