Hi Jase
Re:
My earlier statement of:
"It is also impossible to evaluate the performance of any telescope with a refracting element (Schmidt corrector, Maksutov corrector, doublet or triplet) with the simple knowledge of the Stehl Ratio for one wavelength (usually green), which is sometimes given by telescope manufacturers."
Is indeed true"
Please Show us the proof that this is true yours or by someone else.
Thanks.
Jerry.