A little while ago this great insight into hang glider stability was published on You Tube. If you are a Hang Gliding nut then it is fascinating :
link : Gerolf on Sprogs
I have played with my own sprogs, with varying results, and never feeling very comfortable about doing the adjustments and following test fly. The video inspired me to go buy a $40 digital level and make some measurements.
First set the glider up VG full tight and get the base tube level. I think still air is probably necessary. I was surprised how big of a wedge was needed to compensate 1° of tilt.
Get the keel level.Take the measurements. For me the inside left and right were both 4.3° Outside left was 6.2° Outside right was 6.6°.
Note: results for litespeed RS3.5
I will get to measuring a couple more litespeed S4 models soon.