This ad, is it just me or is the pic a bit.. weird?!

I'm not sure why you think the horse has no shadow - all the shadow on the right of the fence is clearly 'horse' as you can see the upright shadow definitively towards the top on the left, then a gap, then part of the shadow of the horse?

I would say that as the photographer is low down compared to the jump - look at the timing beam on the left of the picture and the fence at the back which is going to be at least 20m away and it's clear the photographer is below the top of the fence, combined with the fact the rider isn't very tall (think my 10yr daughter has longer legs) makes him look bigger
 
The other problem is that the photo has been stretched a little in this ad. The other ads from last September show the same photo but in correct proportions.
 
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