[arpaagent]

Hey guys. I am currently in the possession of two nice copies of the Pentax-F 35-70/3.5-4.5 zoom lens, which is quite a nice little lens with a decent macro function at 70mm. Anyways, while checking them both out, I noticed that the colors of the reflections from the glass are different with the two lenses. It intrigued me so I figured I'd take a few shots and post the differences.

The lens with a warmer tone reflection has a lower SN: 1461296
The lens with a cooler tone refletion has a higher SN: 1814515

Just curious what anyone's thoughts are on this, or if anyone has noticed the same thing? It seems that the newer SN coating reflection seems less bright, so it might produce less flare and better contrast than the lower SN lens.

Oh, and PS first two shots are taken with my new SMC Pentax Fish-Eye 17/4 Lens, and last two are taken with my new SMC Pentax-M 85/2 Lens. Quite proud owner of those two recent acquisitions! (they are cropped for detail FYI)

-Jim

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Last edited by arpaagent; 01-04-2009 at 08:44 AM.

[Blue]

My guess is that the difference is due to different manufacturing runs. It is interesting that there would be this much difference from lot to lot.

[Just1MoreDave]

Just curious what anyone's thoughts are on this, or if anyone has noticed the same thing? It seems that the newer SN coating reflection seems less bright, so it might produce less flare and better contrast than the lower SN lens.

I've seen the same kind of reflection comparison done with the FA43 Limited. I don't know what it means if anything. The site was in Chinese so all I saw were photos.

I know the front coatings on 50mm f2.0 lenses always reflect a rich purple. You don't see the same purple in the 1.7s or 1.4s.