I have the same problem with the sun.

Some horses it seems run better going towards the sun ... while others do better going away from it.

I often wonder if blinkers and shadow rolls have an effect on that. For instance ... if a horse has a single cup partially covering his right eye ... and his eye is in the sun on the backstretch ... but shaded from the sun down the stretch ... how does this affect the horse's acceleration?

Also ... if a horse is equipped with a shadow roll ... and the sun goes behind a cloud so that there are no shadows ... how does this affect his performance?

Any "sun" handicappers out there?