Thanks Alan, Dave, Greg, Marc, Ron, Martin.
BTW hope the title was not too cryptic...( it would be no mystery to fans of South Park)
Indeed, the AP155 is a rare bird.
I'm told due to its high index (and sadly no longer available) NASA comissioned glass, the I/R correction is a little better than the AP160 which followed it. Remarkable seeing the AP155 is also F7, rather than F7.5
AP kindly let me have their one and only prototype TCC to STX adapter, ..however it is unlikely they will shift to commercial production..simply not enough nutters like myself out there
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