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08-06-2010, 10:19 AM   #16
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QuoteOriginally posted by hangu Quote
What we do know is that it gives you another $50 so you can get that M 85mm you've always wanted.
That would be my point, that value is relative. If I have 10k sitting on the floor in front of me, and my choice is either a M 1.7 or M 1.4, or maybe a Zeiss equivalent which I can pop a Leitax converter on, which do I pick? I'm going to buy the 85mm anyway, as the cash is there.

If I only have USD 40 in front of me, this decision is somewhat simplified and I have to wait and save for the 85mm. Maybe I just hire one?

QuoteOriginally posted by hangu Quote
If that portrait of your grandfather had been taken with the 50mm 1.7 instead of the 50mm 1.4, would anyone notice or even know the difference? Would anyone care?
This would be exactly my point, if no one would notice the difference, then the two lenses would have the same rating. If the 50 f1.4 produces a noticeably better image, then the f1.4 should get the higher rating.

Likewise, if the FA 1.4 produces a better image than the f1.4 M, then rating the M higher would be a rather odd decision.


Last edited by whojammyflip; 08-06-2010 at 10:27 AM.
08-06-2010, 10:47 AM   #17
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QuoteOriginally posted by hoojammyflip Quote
That would be my point, that value is relative. If I have 10k sitting on the floor in front of me, and my choice is either a M 1.7 or M 1.4, or maybe a Zeiss equivalent which I can pop a Leitax converter on, which do I pick? I'm going to buy the 85mm anyway, as the cash is there.

If I only have USD 40 in front of me, this decision is somewhat simplified and I have to wait and save for the 85mm. Maybe I just hire one?
Why bother with Leitax when there is a Zeiss available in PKA new?



QuoteOriginally posted by hoojammyflip Quote
This would be exactly my point, if no one would notice the difference, then the two lenses would have the same rating. If the 50 f1.4 produces a noticeably better image, then the f1.4 should get the higher rating.

Likewise, if the FA 1.4 produces a better image than the f1.4 M, then rating the M higher would be a rather odd decision.
I have both of these lenses and they are probably dead even optically. the FA is auto focus and that gives it the advantage there. However, its mf ring is next to a joke. The M gets the advantage there. The build quality on the FA is adequate at best and the M gets the advantage there. The M lacks the A settings so the FA gets the advantage there. I see it as a tie in ratings on the FA & M f1.4 lenses.

Narrowing it down to the image and IQ strictly seems straight forward and would seem to change it from subjective to objective but it does not. What is a good image? (rhetorical) It isn't always about merely sharpness, or contrast, or color. That's where the FA 43mm f1.9 ltd sneaks into the mix and wrecks havoc.
08-06-2010, 10:51 AM   #18
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QuoteOriginally posted by hoojammyflip Quote

This would be exactly my point, if no one would notice the difference, then the two lenses would have the same rating. If the 50 f1.4 produces a noticeably better image, then the f1.4 should get the higher rating.

Likewise, if the FA 1.4 produces a better image than the f1.4 M, then rating the M higher would be a rather odd decision.
but part of the point is, with lenses, using them at their limits, doing things with them that are unique to that lens, such as shooting a 50mm wide open, either for shutter speed or for shallow DOF.

comparing normal images at F8 is useless with respect to the uniqueness of the lens and some of the rating needs to be relitive to what that lens can do, that others can't. I am not sure how that figures into the equation, perhaps, it belongs perhaps it does not,


Maybe the whole idea of ratings is flawed, let me throw a big rock into the pond and see where the ripples go.

What if we, the forum select a "standard" and rate the standard at somewhere between 5 and 8. lenses superior to the standard get higher scores lenses inferior to the standard get lower scores. The standard should be pentax's own lenses, at each focal length and speed. therefore if you are rating a 50mm F1.2 (and there are several not just pentax) you would compare them with the K50mm F1.2, which is the first lens of this FL and speed by pentax. if the A series is better, it goes above the K if it is not as good it goes below.

ratings should also consider optical quality and other features separately. clearly a KA lens may be better from a useablility point of view due to the lens contacts and auto modes on DSLRs.

manual focus lenses may be rated better if they have longer focusing throw, etc, or if they focus closer, etc. I don't know, but it would get complicated.

if we don't want complication, every lens gets an 8 if there is nothing wrong with the photos, 9's and 10's are for above the grade.
08-06-2010, 10:52 AM   #19
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The biggest problem that I see is rating lenses against other lenses. It may be more objective to rate them indirectly against a list of bench marks not too unlike what farfisa suggested early that would include build quality, aesthetics etc. in addition to sharpness, contrast, etc.

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