===================================================
> You can't change the coatings (in the case of MC) w/o redesigning the
> lens? Different glass types I understand, but I didn't think redesign
> was necessary in coating changes.
The multicoatings are formulated so that they match the coatings of the other
elements. It is an optical design and manufacturing balancing act and no
small feat. Hence, you can't replace an element in a single coated Zuiko with
a multicoated one. It has to be another single coated element.
===================================================
technically, it has to be the same element from a lens of the same
optical formula. The coatings may vary from element to get proper
color rendition-- especially single-coated lenses that combine
the purple and amber coatings for proper color balance.
But also Olympus' multicoating changed some over the years so you
probably can't mix and match elements from the same lens with different
versions of multicoating either.
The most expensive and best optical coatings are actually formulated
specially for each melt. when melting the sand or whatver to make
the glass, you end up with slightly different refractive indices
in the glass from each melt due to slight variations in chemical makeup
of the glass, and so the most high end design of coatings will match
the coating to each batch of the lenses resulting from a given melt.
Mamiya does this with their medium format cameras. I don't know
how common it is with 35mm.
Lee writes:
=============================================================
Hey, cool down. I am not doubting that Vince told you what he told you.
I am just telling you what he told *me*, which seems to be directly the
opposite of what he told you.
=============================================================
Sorry, didn't mean to come across as sounding hot under the collar, I
just thought you were claiming that Vince told you that none of the
lenses ever had a change in optical formula, which for sure
isn't true.
Cheers,
Joseph
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