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02-11-2016, 02:29 PM   #31
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QuoteOriginally posted by monochrome Quote
I have numerous intraocular implants to control glaucoma. Parts of these implants are polycarbonate.
Did you have to fine tune the AF on those, or were they OK out of the box?

02-11-2016, 02:59 PM - 1 Like   #32
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They're great lenses, hand-set at the factory by a skilled technician.

Unfortunately the in-lens focusing motor failed and I had to convert them to external focus.

Good thing I kept my K10D or I'd be shipping them to Rupert's place for the conversion.
02-11-2016, 03:03 PM   #33
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QuoteOriginally posted by monochrome Quote
They're great lenses, hand-set at the factory by a skilled technician.

Unfortunately the in-lens focusing motor failed and I had to convert them to external focus.

Good thing I kept my K10D or I'd be shipping them to Rupeet's place.
Ha ha, good man!
02-11-2016, 03:21 PM   #34
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Beer cans are make out of metal, K3 and ltd barrel too.

Nobody would ever think of a beer can to be that wonderful, especially once empty. And it is not that terribly expensive neither.

Glass is no more high end. You have more glass in a low cost wine bottle than most high end lenses.

The name are too generic and don't give an idea of what we speak of.

02-11-2016, 05:35 PM   #35
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QuoteOriginally posted by Nicolas06 Quote

Nobody would ever think of a beer can to be that wonderful, especially once empty.
Don't be silly.......anything that is related to beer is wonderful.

Got me thinking though....... now I know why I love the limiteds....... nothing in them that can't be connected to beer in some way..... bottle or can.....and when you look through them the world is just that much better.
02-11-2016, 05:41 PM   #36
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QuoteOriginally posted by Nicolas06 Quote
You have more glass in a low cost wine bottle than most high end lenses.
Most wine bottles are made of cheap soda-lime glass, lenses on the other hand have greater chemical variety and stricter optical requirements than common cheaper glass types.

QuoteOriginally posted by noelpolar Quote
nothing in them that can't be connected to beer in some way
If you drink enough of it you might see FA77 bokeh.
02-11-2016, 11:49 PM   #37
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QuoteOriginally posted by Digitalis Quote
Most wine bottles are made of cheap soda-lime glass, lenses on the other hand have greater chemical variety and stricter optical requirements than common cheaper glass types.
Sure but the name the same... A bit like plastic component there infinite variety. People want to have glass, not plastic or metal not plastic, but they have no idea of the specific property the plastic used on the barel or for some glass elements has anyway... They just feel glass and metal is high end... Well not always.

02-13-2016, 10:53 AM   #38
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QuoteOriginally posted by Rupert Quote
I can't say much about plastic lenses....my only concern is that plastic tends to attract dust particles because it will hold a charge well. When sanding in my shop, my plastic glasses attract dust quickly....not my glass lenses.

As a retired plumber, I do know that for decades many in the trade rejected plastic. they wanted copper, galvanized or brass. I've replaced thousands of P-traps made of copper or brass that over time corroded and failed......never have seen a corroded plastic P-trap. Nowadays most water and drain lines are some formulation of plastic. Much cheaper, easy to work with and long lasting....most will last longer than we will. Old metal lines often become so full of corrosion they only carry a small % of the water available. Not so with plastic. Think Flint Michigan......would not be a problem there with plastic, it is non-reactive with most contaminants.

Plastic lenses? I won't rule it out, could be a good thing.....time will tell!

Regards!
My eyeglasses are some sort of polycarbonate. They certainly hold up to the abuse I inflict on them. As for plumbing, a couple of years ago I began having pinhole leaks in my copper pipes. Not at a joint but right in the middle. As I began contemplating the task of replacing long sections of pipe and the price of copper, I was prepared to spend the best part of a summer in my cellar. Then, I discovered PEX tubing and Sharkbite fittings and fixed it all on a single afternoon.

I have listened to the "metal means quality" argument for years. I have some mostly plastic constructed lenses that are superb and some all metal lenses that are mediocre at best. At the end of the day, it's the results that count. Our older lenses were constructed with metal parts because the plastics of the day weren't good enough. That is no longer true but it takes a long time to get an "idea" out of peoples heads so high end "quality" cameras and lenses continue to use metal in their construction. Reviews continue to use terms like "high build quality" when something is machined out of metal when it really means nothing these days. It adds unnecessary costs but as long as customers believe the hype, it will continue.
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