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Message: <blockquote data-quote="Vespobuteo" data-source="post: 3296411" data-attributes="member: 120830">that would probably mean bigger prisms, more weight and larger size of the bins,for a flat field and obtaining edge sharpness you probably need more "room"  than you could get in AK-prims of reasonable size and weight,also the extension in length of AK-prisms might make itmore difficult.but the optical gurus here might want to explain that further,what surprises me is the 92% transmission in the SF (even with SP prisms),the amount of glass might be a factor,(thinner/less objective lenses and an integrated focusing lens)</blockquote>