philip_pj wrote:
Wayne, you beat me to the 'Hey Joe' reference, the disappearance of the images earlier threw off this old Jimi fan!

Pressing on regardless, in reference to our thread within a thread re bad copies, I came across a nice quote re manual focus lenses vs AF lenses and found, not for the first time, a serious reference by a serious individual to issues associated with the paltry lightweight mechanisms used to speed the lens elements on their way up and back down the lens seeking acceptable focus. Long sentence apology. I imagine from the date that the speaker refers to Contax Zeiss:

"These Zeiss lenses are superb as are the Leica R offerings. The manual focus is a plus as AF lenses have to be 'looser' in order to focus with any speed. Therefore they are subject to a tiny bit of de-centering not as present with MF lenses. De-centering is a prime factor in loss of sharpness."

If there is one lens type to avoid buying in the high Mp era, it is an old AF lens of unknown or suspect provenance. And we really should not be seeing alarming levels of bad copies in manual focus lenses, let alone ones that take such a large bite from the wallet. The makers know the lenses now have to be very well assembled and QA'd.

Oh, and do give us whatever feedback on the new 25/2 you feel happy to offer. So far it's a confused picture, and after seeing Roger's disturbing pictures (25/2 vs 21/2.8) recently posted here, I do wonder.

Yes, I wanted to try it myself and will post some pictures soon. I just got it today and took some test shots with it and my 24/1.4G
and so far the colors and microcontrast and lack of CA look great and of course look better to me than my 24/1.4G which I expected. Will do some testing shooting against the Stanford Memorial church alla Lloyd C. and compare with ZE 21, 24/1.4G.
25/2's build and smooth focus throw is standard Z* sweetness.

The test shows that on a small part of the image in focus, both lenses have similar sharpness. The other parts of the image are OOF, showing better bokeh characteristics to the Canon.

What else can you draw from the test in relation to quality

staticInc wrote:
I appreciate your comparison. I'm astonished by the OM 24's image "quality". Never thought my little OM 24 could rival the lens I'm planning to purchase...

Enjoy,
Sten

Mr Joe wrote:
@wayne seltzer - Hey, how's it going? Sounds like Zeiss fever in your camera bag. Zuiko fever is much less expensive.

I'm going to wait until my next camera body before I try again. I could probably shoot 90% of what I do with a Zeiss 18 or 21, and a Zeiss 28 or 35. The question is, which one(s) to pick.

@philip_pj - If I had a quarter for every Hey Joe reference, I could retire early.
And ironically, I have a 24-70/2.8L that's very sharp across the frame on my 5D II (along with a Zuiko 18, 21, and 28).

Again, it's not a bad lens or a bad camera, it's the combination of a lens tolerance that's off one way, with a camera that's off the other way. Both can be within spec, and you still don't have a sharp picture. And my testing showed lenses that were off on the left side, and others that were off on the right side -- with the same body. Yet all of my Oly lenses worked fine with either body.
Very strange.

I like the 21 for night photography, to get enough sky in and also gives you some of that wide angle dynamic look. 25 is another good focal length too for me.

Oly 18 is a nice lens though.

I need to do more night photography around the bay area here.

Normal tolerances would not be resovable by the sensor. You have an issue. The problem with observing so many bad copies (with poor tolerances or whatever) is that the maths quickly stacks up against you.

Say 1 in 10 Distagons is a dud (Which is very high). To get 4 is like 1 in 10 to the power 4, = 1 in 10000!

We can exclude bad batches as the lenses are across 2 manufacturers. Buyers of these lenses are experienced and demanding of their equipment, and if this was prevalent then it would be widely acknowledged by now.

Rather than claim Oly's are great and there is an issue with Zeiss / Canon QC as factually as you did, you need to study your equipment / technique to work out what is going wrong.

Mr Joe wrote:
Again, it's not a bad lens or a bad camera, it's the combination of a lens tolerance that's off one way, with a camera that's off the other way. Both can be within spec, and you still don't have a sharp picture. And my testing showed lenses that were off on the left side, and others that were off on the right side -- with the same body. Yet all of my Oly lenses worked fine with either body.

@Skumar25 - This problem is reasonably prevalent and has been acknowledged by Roger Cicala's article linked above. He has more experience with more copies of lenses than anyone. The well known Lloyd Chambers of diglloyd has also acknowledged that this is a problem.

The lens in my blog post was obviously way off. Other samples were more subtle. As I said, I've tried multiple Canon and Zeiss wide angle lenses on multiple 5D Mark II bodies, and my experience is that adapted Olympus OM wide angle lenses are more consistently sharp across the frame than the lenses I've tried from Canon and Zeiss. Of course YMMV.

What I'm very curious to know, is if anyone has a theory why the Oly's are sharper for me. Is it something inherent in the design (size, element construction, distance to focal plane, etc.)?

Mr Joe wrote:
@Skumar25 - This problem is reasonably prevalent and has been acknowledged by Roger Cicala's article linked above. He has more experience with more copies of lenses than anyone. The well known Lloyd Chambers of diglloyd has also acknowledged that this is a problem.

The lens in my blog post was obviously way off. Other samples were more subtle. As I said, I've tried multiple Canon and Zeiss wide angle lenses on multiple 5D Mark II bodies, and my experience is that adapted Olympus OM wide angle lenses are more consistently sharp across the frame than the lenses I've tried from Canon and Zeiss. Of course YMMV.

What I'm very curious to know, is if anyone has a theory why the Oly's are sharper for me. Is it something inherent in the design (size, element construction, distance to focal plane, etc.)?

Can you share your test samples?

Sometimes alignment problems can have reasons in the lens mount also. It's more easy to stress the lens mount with heavy lenses like the Canon/Zeiss than the small Oly

Mr Joe wrote:
What I'm very curious to know, is if anyone has a theory why the Oly's are sharper for me. Is it something inherent in the design (size, element construction, distance to focal plane, etc.)?

Were you born on a mountain? In Greece, perhaps?

I'm starting to think that FF cameras may not be the best way to go after all. On µ4/3 for example and having tested over 400 lenses I only have seen 3 that exhibited corner softness and they were C-mount lenses! I bet APS-C shooters are having similar experiences. When corner softness happens to a noticeable degree it does indeed ruin the photograph.

If owning a FF camera means most of the interesting (on µ4/3) WA and UWA lenses are no longer fun and interesting and that I have to buy a $6k 600mm APO to equal the reach of my current $0.8K 300mm APO then what did I ultimately end up with? A little better DR just doesn't seem worth all the sacrifices in all the other areas.

Is that wrong?

Bifurcator wrote:
I'm starting to think that FF cameras may not be the best way to go after all. On µ4/3 for example and having tested over 400 lenses I only have seen 3 that exhibited corner softness and they were C-mount lenses! I bet APS-C shooters are having similar experiences. When corner softness happens to a noticeable degree it does indeed ruin the photograph.

If owning a FF camera means most of the interesting (on µ4/3) WA and UWA lenses are no longer fun and interesting and that I have to buy a $6k 600mm APO to equal the reach of my current $0.8K 300mm APO then what did I ultimately end up with? A little better DR just doesn't seem worth all the sacrifices in all the other areas.

Is that wrong?



I'd love to discuss this issue in a separate thread devoted to this issue instead of hijacking Kent's thread. I think it's the right question to be asking.

No worries, it's still about WA/UWA quality ... here or new thread, either way I'll chime in my .02.

BTW, David ... if I can hijack my own thread for a moment ... I just learned today that there will be an Ansel Adams exhibit in Mount Vernon, IL starting @ the end of February ... maybe you'll make it this way to see the exhibit. IIRC, it will include 60 or 70 prints, several that he personally made for his daughter from her personal collection.

Would be way cool if regional FM'ers came out to see it. I've let the museum know that I'd be willing to be a docent for the exhibit, but we'll see what happens with that. It'll be at the Mitchell Museum / Cedarhurst ... more info to come.

We now return you to your regular WA/UWA programming.