UK Keratoconus Self-Help and Support Association

Hi
Is there any link/resource which lists that normal/healthy readings of an orb scan test ?

and what about the value of diff ? the less the better ? am I right ?

Thanks

I had the test, earlier (over a month ago) the reading of diff was 0.133mm of posterior view of problematic eye , now it is 0.106mm
there is slight change ? is it for good or worse ? tests were done on same machine