An update on the TS152 f5.9 Modified Achro, I had sent a question to the TS product specialist asking about the use of a reducer on that scope. The reply came in today, which was yes, a 0,8x reducer can be used and would not impact the Image circle up to 42mm. They link in a specific adjustable ED reducer corrector for that scope. That would speed that scope up to just under f4.8. However, it does not mention what the SPOT diagram would look like.
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