10" RC in the making C 102GT OTA POJ 6" reflector Copyscope
Quote:Is baffling of the 2ndary necessary/useful with a closed tube? (If it is, can you explain where the light comes from that the 2ndary baffle would be blocking?)How much extra sky-end beyond the 2ndary do you recommend having (with or w/o a 2ndary baffle)?
Quote:Yep - if you don't baffle the secondary, the primary baffle has to stick forward so far that its end starts to shadow the primary center with an obstruction larger than the secondary. There is an optimal ratio of the two baffles that minimizes that obscuration.