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Message: <blockquote data-quote="OPTIC_NUT" data-source="post: 3223305" data-attributes="member: 121951">Baffling is critical, at least in terms of covering all your bases.If you slice out what you don't need early on, the design doesn't have scattering all through it.Coatings can reduce some lens scattering, but that's a secondary source, and anydust or film on multicoating can light up the 'Hi-Q filter' multicoating represents off axis.Which is to say, short of a clean-room environment, multicoating doesn't take kindly to age.A Takumar SMC lens, for example, can look great to the eye but have some grey level that needs another cleaning.   A little nicotine or out-gassing from within....the layers 'glow'.The thing is, that little ring is never supposed to be lit to make the veil, or if it is hit,it's supposed to be very thin and absorbtive, almost invisble even when lit.  That's how a 1950s field stop works, with its carbon-coated thin diaphragm.  The irises before the prisms are supposed to be beveled, not straight cut.I'm talking about a hood helping a design that falls short, not entirely replacing it.Either there is something to be gained when that glare happens, or its a serious desgn flaw.If you find a long hood helps, that's really just slicing away some of a cone, cutting the wholepath down to protect something that shouldn't see that light or isn't shaped right.</blockquote>