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The Mak design was a long time in gestation, and all CA was eliminated in the process.The corrector does cause CA, but the meniscus diverges the
light by the exact amount required to cancel it out. It doesn't matter much what glass is used for the corrector,[ as far as CA is concerned] as the divergence of the meniscus is adjusted to suit whatever glass is used, although admittedly the less CA the corrector exhibits, the easier it is to cancel it out. No self respecting Mak will exhibit any CA at all, even "budget" level models such as the SW 150 and 180 Maks are CA free.
Even a Mak experimented with many years ago with a meniscus not
designed to cancel out the CA showed only very slight CA, owing to its
focal ratio of f/15.
I have owned two Maks [6 and 8] and used a number of others,[for imaging] and have never seen a trace of CA. I have seen a little occasionally [ visual] caused by el cheapo eyepieces.
raymo
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