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05-29-2010, 07:03 AM   #61
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That may be true

Well that is a great shot. However, to be honest you can get a very similar shot with the DA50-135mm altho would have to stand a bit further back. From my experience the DA50-135mm has superlative picture quality.

Put it this way, if you can see the difference in picture quality on the LCD that is saying something. An you can with the 50-135mm.

Of course the same is probably true for an 85mm F1.4.

05-30-2010, 06:30 PM   #62
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QuoteOriginally posted by wlachan Quote
I am not too certain on Sigma. The major problem with Sigma however, is the choice of materials which wear a lot faster than OEM lenses, and probably why they are cheaper in the first place.
You are "not too certain" about how Sigma lenses are constructed and think "probably" quality of materials is the reason why Sigma lenses are less expensive, in other words, you don't know anything for certain, but still you use multiple posts to discourage people from buying Sigma lenses.

AFAIC, your assessment of third-party lenses being only good in terms of sharpness and being cheap has no leg to stand on. Regarding build quality, we all know that old Asahi/Pentax lenses are very robust but how many times have you heard of SDM (<- Pentax) failures compared to HSM (<- Sigma) failures?

It is OK if you have a personal adversity to buying third-party lenses but I don't see where your sustained recommendation to others can be based on facts.
05-30-2010, 11:38 PM   #63
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By that I meant I disassembled or seen how lenses have been designed and constructed. The last time I disassembled Sigma lenses were a decade ago, and back then their inner structures were poor against Pentax lenses, and that was the reason why so many Sigma lenses self-destructed. The poor choice of materials however, can be seen with ease. The EX finish, rubber, ball bearing and contact pins all worn within a very short period of time. These are great contrast against any OEM lenses. Sigma lenses are being cheaper for good reasons because they cut corners in every little details. They will get the jobs done too, but have higher chance of falling apart (which is no big deal if you know how to fix lenses) and the materials will just wear a lot faster than OEM lenses. However, Sigma has never had trouble developing sharp optics, even though with poor flare control and colour rendition.
05-31-2010, 12:38 AM   #64
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I wouldn't say that all OEM lenses have higher or longer stress tolerances. maybe most but not all of them. as ClassA had mentioned, the SDM mechanism has a higher failure rate than an HSM for Pentax. the K-7's stronger/faster screwdrive AF motor exposed the FA50/1.4's weak construction and the FA28-70/4 had been known for having build quality problems.

but anyway, as long as the lens is not made by a 3rd party company in China, I won't be too nervous about buying a lens.

05-31-2010, 01:54 AM   #65
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QuoteOriginally posted by summonbaka Quote
I've seen quite some FA*85 going around in yahoo auctions here in japan. O_o They are priced just below the $1000 line. But this one in particular has a really bad cosmetic appearance.
???????????FA?85mm F1.4 - Yahoo!??????
ouch. that could explain why there are no bidders.... here comes sweet sweet F A 7 7
05-31-2010, 01:59 AM   #66
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QuoteOriginally posted by wlachan Quote
The last time I disassembled Sigma lenses were a decade ago, and back then their inner structures were poor against Pentax lenses, and that was the reason why so many Sigma lenses self-destructed.
I'm not arguing that but that was a decade ago. Sigma has changed a lot in recent years.

EDIT: I just came across another post of yours in which you write:
I have bought, owned or come across DA14 (x2), FA*24, FA31 (x2), FA43, FA77 (x3), FA100/2.8, FA135 (x2), FA*200/2.8 (x4), DA10-17, DA16-45, DA18-55. Among these, DA14 (x1), FA31 (x1), FA77 (x2), FA100, FA135 (x2), FA*200 (x3) were physically defective (not counting AF or optical defect). Hard to believe really.
And you believe Sigma lenses are even worse than that?

EDIT: I just remembered that Dpreview went through three copies of the DA* 55/1.4 and couldn't get one that didn't have a tilt in the focus plane. Not exactly a role model performance regarding quality control.

I'd like to be a fan of the DA* 55/1.4 (it was designed by Jun Hirakawa, the designer of the FA 77/1.8) but I think its bokeh is too distracting most of the time.

QuoteOriginally posted by wlachan Quote
The EX finish, rubber, ball bearing and contact pins all worn within a very short period of time.
Is that your personal experience? With which lens?
I have two Sigma EX lenses and haven't observed any of this. Admittedly, I treat them well and haven't owned them for decades yet.

QuoteOriginally posted by wlachan Quote
Sigma lenses are being cheaper for good reasons because they cut corners in every little details.
I'm not sure they cut corners in every little detail. The aperture blades of my Sigma 28/1.8 close so much more nicely than those of my Pentax FA50/1.4. The latter show jaggies until about f/2.8. None of this with the Sigma and the symmetry is perfect. In another thread you don't deplore the (alleged) discontinuation of the FA50/1.4 because you've seen copies fall apart. I think that this is an exaggeration too but I agree with you that the built-quality of the FA50/1.4 is not superior to Sigma EX lenses, on the contrary.

Third-party lenses have to be cheaper (or significantly better) in order to be competitive against OEM equipment which is the first natural choice for everyone.

QuoteOriginally posted by wlachan Quote
However, Sigma has never had trouble developing sharp optics, even though with poor flare control and colour rendition.
Colour balance might be different for some lenses but I never heard anyone call the colour rendition "poor". I'm sure I could pull out a lot of reviews testifying great flare control for Sigma lenses, however, this is not my fight.

Last edited by Class A; 06-07-2010 at 04:10 AM.
06-04-2010, 07:31 AM   #67
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just got some unconfirmed reports from a source. the person said that if you like the Sigma 50/1.4, you are in for a real treat for the Sigma 85. he said that the 85 is a tweaked version of the 50mm when it comes to coating and lens design. as far as CA goes, it comes very close to APO quality. he said that the lens is already a monster at f1.4, and a clear runaway winner at f2-f2.8. HSM works like a charm and a fantastic feature.

I don't mind the skeptism, but this report certainly getting me optimistic a lot.

06-04-2010, 08:50 AM   #68
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Shipping starts in July for U.S. , dunno in other territories.
06-05-2010, 12:41 PM   #69
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QuoteOriginally posted by nater Quote
Considering the Zeiss 85mm f/1.4 ZK Planar T* goes for $1200 or so, $900 doesn't seem that outrageous for a Sigma AF lens, especially if the optics are good.
QuoteOriginally posted by patk Quote
the zeiss can be purchased for under $1k (new) on ebay from popflash - a very respectable retailer. even though i would personally prefer af, the sigma would have to be stellar rather than good to match the zeiss and command $900. looking forward to the reviews.
Yeah! if the Sigma is anywhere near the perfromance of the Zeiss 85/1.4, I will definitely get one. But, not even for a nano second do I think Sigma can replicate the Zeiss 85/1.4......
06-05-2010, 01:34 PM   #70
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QuoteOriginally posted by pcarfan Quote
Yeah! if the Sigma is anywhere near the perfromance of the Zeiss 85/1.4, I will definitely get one. But, not even for a nano second do I think Sigma can replicate the Zeiss 85/1.4......
Do you think they can replicate the IQ etc of the Jupiter?
06-05-2010, 02:03 PM   #71
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QuoteOriginally posted by Blue Quote
Do you think they can replicate the IQ etc of the Jupiter?
or the FA*85/1.4?

anyway, each lens is to each his own strengths and weaknesses. it won't do Sigma any good if it's not unique and say that the lens is just a knock-off version of the zeiss.

I would however be interested on the color rendition of the Sigma if it has that similar cooler tone of that of the Sigma 50/1.4, or warmer (I prefer warmer). and also the vividness and accuracy of the color. although these things can be done thru post-processing, it would be nice that we dont have to do some work or atleast identify the lens for it's real potential w/o a bit of pp assistance.
06-05-2010, 02:05 PM   #72
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I think there's a reason that most fast lenses do not use hyper-corrected optics. I could not care less about the sharpness, but in such lenses the bokeh is VERY important. I hope Sigma has concentrated on that part too.
06-05-2010, 02:15 PM   #73
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QuoteOriginally posted by Asahiflex Quote
I think there's a reason that most fast lenses do not use hyper-corrected optics. I could not care less about the sharpness, but in such lenses the bokeh is VERY important. I hope Sigma has concentrated on that part too.
I don't think you have enough ~ 77-85mm lenses so you will definitely be a candidate for this new Sigma!
06-05-2010, 02:17 PM   #74
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QuoteOriginally posted by Asahiflex Quote
I think there's a reason that most fast lenses do not use hyper-corrected optics. I could not care less about the sharpness, but in such lenses the bokeh is VERY important. I hope Sigma has concentrated on that part too.
Yes, the bokeh should be highly considered in this focal length. the Voigtlander for example is a highly corrected lens thanks to it's APO design. although sharp, the bokeh is pretty much mediocre good, not even satisfactory good for my taste. and the slower aperture speed made it even more less desirable and less poppy images. although I believe it would be great for landscape use.
06-05-2010, 05:54 PM   #75
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QuoteOriginally posted by Pentaxor Quote
just got some unconfirmed reports from a source. the person said that if you like the Sigma 50/1.4, you are in for a real treat for the Sigma 85. he said that the 85 is a tweaked version of the 50mm when it comes to coating and lens design. as far as CA goes, it comes very close to APO quality. he said that the lens is already a monster at f1.4, and a clear runaway winner at f2-f2.8. HSM works like a charm and a fantastic feature.

I don't mind the skeptism, but this report certainly getting me optimistic a lot.
I dont like the bokeh on the 50/1.4 and is the reason I bought the Pentax 55/1.4 ( https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/91916-pentax-d...tml#post945277 )

I hope for everyone that doesn't own the FA* 85 this isn't the case. As for "clear runway winner," I'm dubious. I think that the only way it's going to win is that the FA* isn't in production anymore, and a shame that is.
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