Shooting in the gym. need help on setting!

[feRRari4756]

If you find a F1.8 zoom let me know, F2.8 is only 1 stop better and these look 2 or more stops under

Okay, but isnt f/2.8 probably the largest aperture zoomlens yuo can get?

 

[jlykins]

I've seen f/2.0 but never anything smaller...