I took these shots of my daughter practicing her tumbling skills with my new $89.00 50mm f1.8. For this specific purpose, taking fairly close action shots in low light without a flash, I think the lens was a good purchase.
I have lots of better individual shots but this is the best series I have and I think it makes an interesting sports and action sequence to see a standing backflip start to finish. 1/400, f1.8, iso3200, +0.3step. cc
I did try to level these but because of the perspective angle, if I level the floor the wall is out and if I level the wall the floor is out, so I just tried to find a compromise. Following Rod's advice, I shot these from a lower angle and included her expression before takeoff.