[osv]

Why would I need to acknowledge anything?

that's exactly right, why indeed would you want to have an adult conversation we got that already.

people with open minds will want to understand the differences in aspherical elements, tho; why they fail, and what to look for.

that's what i've provided here.

[BigMackCam]

that's exactly right, why indeed would you want to have an adult conversation we got that already.

people with open minds will want to understand the differences in aspherical elements, tho; why they fail, and what to look for.

that's what i've provided here.

"We" got that? You and all your loyal followers?

Oh, I have an open mind, and I enjoy an adult conversation, but you insist on telling me what I do and don't know, can and can't see. That's not a conversation. There's no mileage in discussing anything with you if that's your attitude.

What you provided here simply shows that you aren't open-minded to any other scenario than the one you decided is correct. Me? I was prepared to be convinced... Ah well. All the best to you.

[osv]

"We" got that? You and all your loyal followers?

Oh, I have an open mind, and I enjoy an adult conversation, but you insist on telling me what I do and don't know, can and can't see.

ok, i'll give an example... you posted one small unlinked pic in this thread, without specifying what aperture it was shot at, i don't see any exif showing?

what conclusions should be drawn from incomplete info? did you shoot it at f/11, not knowing that dof hides some lens defects? etc...

i'm really trying to understand what you actually see, but you aren't making it easy

i think you are probably right about your lens being fine, just sayin'...

[BigMackCam]

ok, i'll give an example... you posted one small unlinked pic in this thread, without specifying what aperture it was shot at, i don't see any exif showing?

what conclusions should be drawn from incomplete info? did you shoot it at f/11, not knowing that dof hides some lens defects? etc...

i'm really trying to understand what you actually see, but you aren't making it easy

i think you are probably right about your lens being fine, just sayin'...

The pic was at f/7.1 (which, I do realise, will start to reduce - but probably not eradicate - the effects of de-centering) - not by design, that's just what it was set at as the lens was already on my K5 and had been used earlier in the day at that setting. I get similar results at wider apertures - you can choose to believe that, or challenge me on it if you wish. Is it possible there is any de-centering? Yes, it's possible, but none that has reared it's head in any of the shots I've taken with that lens, or the example I owned before it. And whether you believe me or not, I know what to look for.

I don't doubt you've experienced problems with your lenses. I choose to take what you've experienced at face value - why wouldn't I? What I object to is your assumption that I don't acknowledge what someone else you refer to has said (simply because I didn't mention it specifically in my post, doesn't mean I think roger at lenstip is ignorant) or that I don't see what I know I do see (the issue with your DA15 image toward the right hand side and particularly the upper right quadrant, for example - which I could see even without going to the flickr link).

I even acknowledged that a hybrid aspheric element is indeed one - of many - parts of a lens that adds complexity and hence is a potential area for failure. What I don't acknowledge - only because nothing has been provided to suggest otherwise - is that hybrid-aspheric-element-related issues are common-place, or at least considerably more common-place than any other optical issues with lens manufacture and hence apparent in sample variation. But, I still am prepared to be convinced. That's me being open-minded.

To add some balance here, I had problems with two copies of the DA16-85. One had a loose element or mechanism somewhere, such that the viewfinder image moved up and down when auto-focusing. The second was de-centered, and had a much reduced but still discernable up/down movement of the viewfinder image. I researched and found several people who had experienced the same problems with their copies of the lens. Now, with regard to the up / down movement, that has indeed left me thinking there could well be a design issue with that lens. And I've told several people on this forum about it, so they are aware of the potential issue - but I haven't gone so far as to tell anyone there is a general problem with that lens design.

I'm going to leave it there now... We've both said what we think is relevant. I really don't want to argue with you or anyone else - I genuinely don't enjoy it. Your responses to me pushed my buttons, and I reacted in a way I don't like, so apologies for that.

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Last edited by BigMackCam; 03-07-2016 at 04:37 PM.

[ChristianRock]

Wow. Complete thread hijack.

[paulh]

Hey, I really like my copy of the A35/2.8! No complaints about IQ, and it has one of the smoothest focussing rings I've used. Enjoy!

[KC0PET]

Hey, I really like my copy of the A35/2.8! No complaints about IQ, and it has one of the smoothest focussing rings I've used. Enjoy!

Good deal and thanks, Here is a photo I took with it over the weekend.