CZ 16-80 almost killed A700 review

Started Sep 25, 2007 | Discussions
assafb
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CZ 16-80 almost killed A700 review
Sep 25, 2007

After Dave Etchels reported finding embarassing A700 focus misses on the ongoing review's forum, I asked him to check whether it could be related to the lens, and indeed it was the notorious CZ 16-80 bug.

I'll say for Dave Etchels that it is remarkable how responsive and flexible he could be when A700 is only one of several reviews undergoing at the same time. He already reshot all JPGs as XFine to the forum request, tried the theory that RAW would suffer less from NR, and retried focus accuracy tests with CZ alternatives.

The thread is here:
http: http://www .photo-forums.com/WebX?14@49.yBNDb4gh7an.7@.eea646c/14

George Evans
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Re: CZ 16-80 almost killed A700 review
In reply to assafb, Sep 25, 2007

You could be right. Is it correct that the Sony launch in Italy was using the CZ 16-80 on the A700? Could that account to some degree for some poor images from the launch?

I read a comparison of lenses in a recent magazine (Tamron, Sigma, Nikon, CZ 18-70) and the CZ 16-80 came out poorly.

George Evans

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tomslot
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Re: CZ 16-80 almost killed A700 review
In reply to assafb, Sep 25, 2007

Whoops, it looks like I should consider canceling my CZ 16-80 order.. any extra info on this issue will be greatly welcome.

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Richard B.
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Re: CZ 16-80 almost killed A700 review
In reply to tomslot, Sep 25, 2007

I am not sure how widespread this problem is. I have the CZ 16-80 and have never had focus problems. I have seen some thread regarding variability of build quality, so I might be inclined to order from a vendor with a good return policy.

However, once you have good one the IQ is superb!

tomslot wrote:

Whoops, it looks like I should consider canceling my CZ 16-80 order..
any extra info on this issue will be greatly welcome.

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dnjake
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tester responsibility
In reply to assafb, Sep 25, 2007

assafb wrote:

After Dave Etchels reported finding embarassing A700 focus misses on
the ongoing review's forum, I asked him to check whether it could be
related to the lens, and indeed it was the notorious CZ 16-80 bug.

I'll say for Dave Etchels that it is remarkable how responsive and
flexible he could be when A700 is only one of several reviews
undergoing at the same time. He already reshot all JPGs as XFine to
the forum request, tried the theory that RAW would suffer less from
NR, and retried focus accuracy tests with CZ alternatives.

The thread is here:
http: http://www .photo-forums.com/WebX?14@49.yBNDb4gh7an.7@.eea646c/14

Well his statement that they don't routinely check for focus accuracy suggests some limitiation in the quality of their tests. The reality is that it has been common for demanding Canon professionals to send all their L lenses plus a particular Canon body into Canon service so that it all can be calibrated for accurate focus. It is not reasonable to count on focus accuracy. I would also say that from his thread it is still far from clear what the story is.

What would be good is if he ran his SLRgear.com tests on the CZ 16-80 and a number of other Sony lenses. It would be very helpful to have the results of those tests to compare the 16-80 and the 16-105.

Generally, I find Imaging-Resource to be one of the best web sites for equipment testing. But I think the focus issue is only one of several that makes comparison of images from different cameras difficult. Another question is how carefully they control the light level between different tests. Probably they do a reasonable job. But they don't seem to specify the level quantitatively. If they are not careful about the focus, one wonders. A more obvious issue and one that is difficult to deal with is the difference of image processing between cameras. It was quite obvious from the A700 and 40D comparison I made that the 40D images had a tonal curve with more contrast than the A700 images. That contributed significantly to their perceived quality.

It might be that they would be better off with fewer tests done more carefully.

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ab012_KM7D
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Re: CZ 16-80 almost killed A700 review
In reply to Richard B., Sep 25, 2007

ditto my experience

actually - with respect to focus accuracy - my 16-80 is more accuracte than the 17-35D or the 17-35G if anything (i got all three with me right now for a different reason)

Richard B. wrote:
I am not sure how widespread this problem is. I have the CZ 16-80 and
have never had focus problems. I have seen some thread regarding
variability of build quality, so I might be inclined to order from a
vendor with a good return policy.

However, once you have good one the IQ is superb!

tomslot wrote:

Whoops, it looks like I should consider canceling my CZ 16-80 order..
any extra info on this issue will be greatly welcome.

-- hide signature --
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Bernard

AS/SSS rocks!
lens reviews and more on dyxum.com!

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ILikePhotography
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Re: CZ 16-80 almost killed A700 review
In reply to assafb, Sep 25, 2007

assafb wrote:

After Dave Etchels reported finding embarassing A700 focus misses on
the ongoing review's forum, I asked him to check whether it could be
related to the lens, and indeed it was the notorious CZ 16-80 bug.

I'll say for Dave Etchels that it is remarkable how responsive and
flexible he could be when A700 is only one of several reviews
undergoing at the same time. He already reshot all JPGs as XFine to
the forum request, tried the theory that RAW would suffer less from
NR, and retried focus accuracy tests with CZ alternatives.

The thread is here:
http: http://www .photo-forums.com/WebX?14@49.yBNDb4gh7an.7@.eea646c/14

Curious, I think it within reason to expect SONY and the test facility to provide more than one lens with a review kit?

In particular a prime lens and then a zoom. As for the CZ1680 mine is just fine thank you. Some folks have discovered repeatable flaws in some and these having been well documented. . . so any reviewer should verify those issues up front before evaluating the primary topic of the a700 body.

BTW has anybody ever linked the cz1680 flaws to a production run or similar fault?

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Ken_5D
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Re: tester responsibility
In reply to dnjake, Sep 25, 2007

dnjake wrote:

assafb wrote:

After Dave Etchels reported finding embarassing A700 focus misses on
the ongoing review's forum, I asked him to check whether it could be
related to the lens, and indeed it was the notorious CZ 16-80 bug.

I'll say for Dave Etchels that it is remarkable how responsive and
flexible he could be when A700 is only one of several reviews
undergoing at the same time. He already reshot all JPGs as XFine to
the forum request, tried the theory that RAW would suffer less from
NR, and retried focus accuracy tests with CZ alternatives.

The thread is here:
http: http://www .photo-forums.com/WebX?14@49.yBNDb4gh7an.7@.eea646c/14

Well his statement that they don't routinely check for focus accuracy
suggests some limitiation in the quality of their tests. The reality
is that it has been common for demanding Canon professionals to send
all their L lenses plus a particular Canon body into Canon service so
that it all can be calibrated for accurate focus. It is not
reasonable to count on focus accuracy. I would also say that from
his thread it is still far from clear what the story is.

What would be good is if he ran his SLRgear.com tests on the CZ 16-80
and a number of other Sony lenses. It would be very helpful to have
the results of those tests to compare the 16-80 and the 16-105.

Generally, I find Imaging-Resource to be one of the best web sites
for equipment testing. But I think the focus issue is only one of
several that makes comparison of images from different cameras
difficult. Another question is how carefully they control the light
level between different tests. Probably they do a reasonable job.
But they don't seem to specify the level quantitatively. If they are
not careful about the focus, one wonders. A more obvious issue and
one that is difficult to deal with is the difference of image
processing between cameras. It was quite obvious from the A700 and
40D comparison I made that the 40D images had a tonal curve with more
contrast than the A700 images. That contributed significantly to
their perceived quality.

It might be that they would be better off with fewer tests done more
carefully.

I have to say I agree.

What shocked me was finding that the 40D test set was made at 100mm and the Sony A700 at 60mm and that the same type of lens was used if I am reading right.

Because of that we have had people who seem to have a personal need to trash a good camera take the soft edges wich anyone can see are soft edges and try to claim it is a bad jpg processor or NR..

Right now the Imaging resources tests with 100% files are not great comparisions, because it appears that the lens type was no normalized.

A few years ago video card drivers started shipping with specific code to win common tests even though it didn't help the actual user in most cases. They got called on it and several reviewers started looking for and calling out the cheats.

If reviewers are going to just shoot what is given them. I expect to see better lenses, custome tuned lenses going out to reviews. I also based on what I have seen on this forum expect to see makers opting to over sharpen jpgs to meet the deafult shooting tendencies.

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tomslot
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Re: CZ 16-80 almost killed A700 review
In reply to Richard B., Sep 25, 2007

Thank you all guys for the feedback,

I am already aware that this lens is notorious for factory faults (but otherwise gives excellent results). Can you give any tips on how to test it in the shop? I am going to use a test chart from this article: http://photo.net/learn/focustest and try different focal lengths. Anything else I should pay attention to?

The other thing its alleged incompatibility with A700, any other input on that?

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