What's the difference between a PV measurement and RMS ?
My 12" is apparently 1/16th RMS
My 6" is 1/4th PV
What does that mean then?
this might help mate......
http://www.oldham-optical.co.uk/Optical.htm
That has to be one of the worst designed websites I have seen for a long time.
Lots of information though....
That's a very interesting article John.
Ok cool so my mirror is better than 1/16th rms (the ones I have seen measured seem to be 1/24+ RMS) so that's about 1/4 wave or better PV, good, actually the 6" is 1/6th PV, excellent so they should both be very good.....