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01-30-2014, 07:25 PM   #76
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QuoteOriginally posted by DragonLord Quote
The lens has been confirmed as sharp corner to corner.

--DragonLord
Happy it worked out for you!!

01-30-2014, 07:28 PM   #77
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QuoteOriginally posted by tibbitts Quote
Almost all manufacturers discard or recycle items that don't meet specifications. The only debate is with regard to lenses is:

1. is there any testing at all?

2. if so what are the tolerances relative to the specifications?

It's also possible that the only testing relative to a specification is, for example, physical alignment of the components. Sometime each component can be very close to specified alignment, but the aggregate of several tolerances being off can combine to result in poor performance. It's possible that each individual tolerance is being measured, but not the resulting aggregate performance. We won't know, unless somebody involved on the manufacturing side tells us.

I don't believe the UPS scenario as affects a high percentage of lenses, since if it did, the manufacturers would respond by (relatively low cost) packaging improvements. Some extra foam is cheaper than having a high percentage of lenses returned as defective.
Well then we seem to be at an impasse. It seem to be your contention that there is no testing and that Pentax is shipping defective product. Personally I find that hard to believe. I have no idea how we would resolve this impasse. I just know in the old days they used to put the number of the guy who inspected the lens. I haven't seen one of those for a few years now, but I assume they are still there.
01-30-2014, 07:43 PM   #78
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QuoteOriginally posted by normhead Quote
I just know in the old days they used to put the number of the guy who inspected the lens. I haven't seen one of those for a few years now, but I assume they are still there.
The guys who inspect lenses cost money and we know Hoya liked to eliminate things that cost money. I contend that Ricoh has invested in improved manufacturing processes, which in the modern world means a company needn't pay guys who cost money to inspect every item off the line. Instead they buy machines to make things. Machines don't get drunk the night before, get divorced, get sick, have a bad day, get mad at the Supervisor or just screw up. They don't get paid vacation, seniority or a pension. They just do the same exact thing, over and over.

Then they draw a statistically significant number of samples off the line at random and test them rigorously.

But I don't know anything.
01-30-2014, 09:00 PM   #79
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QuoteOriginally posted by DragonLord Quote
The lens has been confirmed as sharp corner to corner.

--DragonLord
Awesome - your patience and persistence paid off!

01-30-2014, 09:48 PM   #80
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QuoteOriginally posted by normhead Quote
Well then we seem to be at an impasse. It seem to be your contention that there is no testing and that Pentax is shipping defective product. Personally I find that hard to believe. I have no idea how we would resolve this impasse. I just know in the old days they used to put the number of the guy who inspected the lens. I haven't seen one of those for a few years now, but I assume they are still there.
Unless someone involved in the manufacturing process comes forward with an explanation, we'll never know what's tested, or how. But regarding Pentax shipping defective product: how else can I explain the corner and side variation examples that I've posted in other threads - and that others have posted or described so often? The WR I have now is clearly and repeatedly blurry in the lower left corner at sub-100mm. It's not a question of some fractional lines per millimeter difference from corner to corner; it's glaringly blurry, without needing 100% pixel peeping to see it.

Having said that, it's great to hear that the OP has seemingly found the ultimate 60-250mm DA*, so congratulations are in order.
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