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hello brian
it is interesting looking at the photos of that wonderful (i am sure it is) scope
but on another matter........ what is an apochromatic lens? can it actually be a doublet as the tak 90?
i have always thought it could be, as long as all the colours combine to a single focus, and if a doublet attains this then it is "apochromat"
however recent reports and blogs from CN suggest that you need a 3 element design to be labelled "apochromat"
pat
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