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Calculating backfocus
Hi guys,
I was looking at the SW Espirit 120 triplet apo and noted that it stated the visual backfocus of the scope listed at 225mm from the end of the focusser tube. Am I correct in assuming that, with the focusser fully racked in, 225mm is the extra distance the image would focus for a camera chip?
What about an eyepiece?
Would this also mean that my Denkmeier bino viewers (114.5mm needed) and a 90 degree star diagonal (95mm needed if I measured right) for a total of 209.5mm would actually come to focus (depending on eyepiece) without needing to modify anything?
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