I have attempted to summarize all the information I could gather about these lenses' serial numbers and how they correspond to their image quality (IQ). I hope this summary serves its purposes when you are buying these lenses.
Serial Numbers:
- less than 1,xxx,xxx - single coated unless it has the MC label.
- higher than 1,xxx,xxx - most likely multi-coated.
- higher than 1,050,xxx - definitely multi-coated.
- Silvernose - these versions are identified by the chrome/silver edge of the filter rim. They are the earlier versions (s/n usually below 5xx,xxx) the OM 1.4 and usually preferred for B&W photography or Videoing using DSLRs these days.
- Blacknose - these versions are identified by the black edge of the filter rim and due to being the later versions are thought to be sharper having better image quality than their silvernose cousins.
IQ by serial & varieties:
s/n less than 1,xxx,xxx non-MC -- Low contrast. Moderately sharp.
s/n less than 1,xxx,xxx MC -- High contrast except @ f1.4. Noticeably sharper than above.
s/n greater than 1,xxx,xxx MC -- High contrast. Sharper than the one above.
s/n greater than 1,050,xxx MC -- High contrast. A tic better than the one above only on corners.
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| Really low serial number non-MC |
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| Serial number under 1,xxx,xxx MC version |
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| Serial number over 1,xxx,xxx MC version - notice the green cyan tint on the front element |
Personally, I believe that even though the difference is just perceivable between the single-coated and multi-coated versions, it is not extremely noticeable unless the photograph is blown up to poster sizes. It is definitely not noticeable for video purposes making it a very handy lens for videoing snippets of weddings.
