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11-10-2011, 12:29 PM   #1111
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QuoteOriginally posted by Emacs Quote
OMG
It shouldn't be exactly the same bug. But, the fact an image is essentially blurred if SR is ON shows it's the SR issue. And I'm not the only one who have troubles with it. I know at least three other people who have buggy SR too.
So, you don't know how to handle contrast and SR too now? I have I already said that the Iphone is THE camera for you?

11-10-2011, 12:34 PM   #1112
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QuoteOriginally posted by Clavius Quote
Nice site for measuring camera sizes.

Wha! The Nex 7 is only 2cm smaller then the K5. Just as wide, only 2cm shorter.

So much for extra mobility. Bye bye...
Well... It's not even half the weight!
11-10-2011, 01:28 PM   #1113
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QuoteOriginally posted by Clavius Quote
Nice site for measuring camera sizes.

Wha! The Nex 7 is only 2cm smaller then the K5. Just as wide, only 2cm shorter.

So much for extra mobility. Bye bye...
I would add : so many pixels for so low performance and protudent (Sony E) lenses...

But that's far from the thread's title...
11-10-2011, 02:01 PM - 1 Like   #1114
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QuoteOriginally posted by Clavius Quote
So, you don't know how to handle contrast and SR too now? I have I already said that the Iphone is THE camera for you?
Man, don't be too pathetic
I know about image processing quite a lot. And I'm too lazy to do the work the lens (which is quite pricey) supposes to do itself.
I'm very doubt you are capable enough to get this, but I'll try to explain it anyway with two samples, one taken with CZ Distagon 21 and one with 15Ltd:

Distagon: 8 seconds exposure


15Ltd: f8, 6 seconds exposure


So, the distagon works as a DR compressor compared to 15Ltd. This difference shows what I meant under the «contrast». This is not the local contrast, but the scene contrast between light and dark parts of an image. The light parts are already about to be burnt out but the parts in shadows didn't take enough light yet. And thus the scene gradient tends to be large on the transitions.
With the distagon the gradient is not so strong, and the scene itself looks more smooth.
So, either try to make the DA ltds to perform like these, or to stop calling these overpriced things "Limited". The thing they aimed to do is to produce tasteless overcontrasted pics with cartoonish colors. Period.
One can avoid these problems (part of them actually. 15Ltd is already killed many midtones), but I don't see the point why to buy these things, if, for example, the NX system provides better lenses for less money.

I really doubt you can get this, though

11-10-2011, 02:06 PM   #1115
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Emacs: What are these images supposed to show? The main difference I see, is that the lower image is more exposed.
11-10-2011, 02:24 PM   #1116
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Here is sample with exposured up distagon shot. It's still more uniform.
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PENTAX K-5  Photo 
11-10-2011, 02:42 PM   #1117
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QuoteOriginally posted by Emacs Quote
So, the distagon works as a DR compressor compared to 15Ltd. This difference shows what I meant under the «contrast». This is not the local contrast, but the scene contrast between light and dark parts of an image. The light parts are already about to be burnt out but the parts in shadows didn't take enough light yet. And thus the scene gradient tends to be large on the transitions.
With the distagon the gradient is not so strong, and the scene itself looks more smooth.
Emacs, can you explain the mechanism by which a lens would respond to light in the way you describe? I don't understand how that would work.

I understand how a similar effect happens with sensors — there's simply a counter which gets full.

Are you saying that the lens transmits brighter light better than it does dimmer light?
11-10-2011, 03:01 PM   #1118
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Gradient rendering on Zeiss lenses

Hi Emacs,

Thanks for posting the 15 Ltd & ZK 21 photos. I have been wondering how they compare since the 15 have been so highly praised.

As a user of Zeiss lenses for over 2 decades and from you photos, I agree the 21 has way better highlight to shadow gradient than the 15. This attribute translate to less darkroom work for films & Photoshop processing for digital images during enlargement. Lecia, Voigtlander, Zeiss and a few Canon lenses are oozed with this attribute IMO.

11-10-2011, 03:48 PM   #1119
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low-contrast lenses and blackness

Okay, I think I get what's going on. The older lens designs allow more veiling glare — stray light. This reduces shadow detail, and makes the blackest blacks less black. (Hence, "veiled".) The JPEG processor, however, sets a black point so that the almost-blacks are rendered as absolute. This is independent of the exposure of the highlights — the stray light applies there as well. However, the midtones may indeed appear expanded simply because the black point is set higher.

The thing is, one can easily get this lower-contrast effect from a lens with better overall contrast simply by opting to cut out the shadow detail. See attached image for a crude attempt at this — it would obviously be more nicely done in RAW conversion. (You can see that it's a bit posterized; that's because the JPEG doesn't have much left to work with.) So, you may indeed want to change the settings a little bit, either in your RAW workflow or in the in-camera JPEG processing. Experiment with turning down the overall and shadow contrast in the tone curves setting screen and you may get results you like better. You may also want to underexpose a bit more and then "push" in RAW processing.

It's one thing to complain, but I think spending a little time learning to use your equipment to its fullest is a better course. As you say, it's an expensive lens, so rather than being disappointed (and it certainly sounds like you are), I think you really can get a rendering more like that which you find pleasing.
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Last edited by mattdm; 11-10-2011 at 08:21 PM.
11-10-2011, 03:51 PM   #1120
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QuoteOriginally posted by MJL Quote
Thanks for posting the 15 Ltd & ZK 21 photos. I have been wondering how they compare since the 15 have been so highly praised.
Wouldn't the 21mm Limited be a better direct comparison?

QuoteOriginally posted by MJL Quote
As a user of Zeiss lenses for over 2 decades and from you photos, I agree the 21 has way better highlight to shadow gradient than the 15. This attribute translate to less darkroom work for films & Photoshop processing for digital images during enlargement. Lecia, Voigtlander, Zeiss and a few Canon lenses are oozed with this attribute IMO.
Keep in mind that what I suggest above isn't necessarily more darkroom work, since it's basically just presets altered to taste for the lens in general, not absolutely for every photo individually. Of course, you can always get the best results by working with each individual image carefully; in some cases, you may prefer the shadow detail.
11-10-2011, 04:59 PM   #1121
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Why do you still own the lens if you have and prefer the Zeiss 21mm? There are plenty of people out there who can get incredible images and don't blame their lenses. Personally, I think the build quality, size and design of the DA Ltds make them worth their price.

I think people who buy these silly expensive lenses just go out of their way to justify their ridiculous expense. The DA Ltds just aren't expensive enough to be considered lust worthy to them.
11-10-2011, 05:07 PM   #1122
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Eh, aren't we supposed to turn of SR when mounted on a tripod?
11-10-2011, 08:57 PM   #1123
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QuoteOriginally posted by Fontan Quote
Eh, aren't we supposed to turn of SR when mounted on a tripod?
When you put it on a tripod just set the 2 second timer and SR is automatically turned off. This is the best way for my use.
11-10-2011, 11:35 PM - 1 Like   #1124
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Emacs will not explain. He has done this to many topics. And he's doing it again to this one now.

This thread is about FF Pentax. Not about Emacs inabilities.
11-11-2011, 01:30 AM   #1125
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yes unfortunately emacs thinks a high contrast lens is a bad thing somehow now...

Emacs should blame the bad sensor with limited dynamic range. You shouldn't be looking for low contrast lenses to "compress" ( which in fact we can argue that but lets leave it like that for the sake ) . Contrast is a personal preference... just because digital sensor suck ass with high contrast lenses that doesn't mean you should be looking for low contrast lenses to equalize the DR of your scene( thus producing "more pleasing images" ). Sensors are known for their limited dynamic range and high contrast ( compared to our eyes ).

Why don't you show us the same comparison on a low dynamic range scene or same scene and use something like a high dynamic range negative film. I did my tests, have you ? You'll see that now there is nothing good about your low contrast CZeiss... technically speaking. Artistically you might still prefer the low contrast ( i wouldn't ) but it would have nothing to do with the high contrast/cartoonish colors you talk about. If you used a normal contrast film you would have the photo you so much love with the 15ltd ( smooth transitions between highlights etc... good contrast ) and you would say the 21 now looks washed out and low contrast so what you are basically doing is using a low contrast lens to overcome your sensor inabilities and then you go on blaming high contrast lenses ( for example limited, although I would say FA limited ares not high contrast lenses ) because todays sensors are crappy. You are using a high contrast lens in a very contrast scene with a very bad medium(sensor) drange-wise. Start blaming your sensor I say

Now let's go back to the FF talk.
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