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08-08-2013, 02:03 AM   #241
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QuoteOriginally posted by Class A Quote
I've read articles by him and it nice being able to put a face to a name.
Yeah, he's a very nice guy. Was lucky to meet him in Cologne once.

I was researching info about the optical design (#elements etc.) of the new 1.4/55 and found the video. The info belongs to a Zeiss blog article
-> From brand personality definition to prize-winning design | Camera Lens Blog

Dr. Nasse wrote an article about what makes a Distagon a Distagon too:
-> http://blogs.zeiss.com/photo/en/wp-content/uploads/2011/12/en_CLB41_Nasse_Le...s_Distagon.pdf

BTW, it seems that there is a brand new article which made it to the DPR title page yesterday
-> No compromises | Camera Lens Blog

So, the lens is attracting quite some attention. If only it were AF I shot the lens at PK last year (even have a few RAWs made with the lens) and one would like to have at least focus peaking or any other means to confirm exact focus knowing this lens' capabilities ...

QuoteOriginally posted by Digitalis Quote
The only way to empirically confirm whether this lens is an altered MEdium format lens is to simply use it on an ALPA FPS equipped with a MFDB with a 35mm lens adapter.
I can't see how this would be able to confirm anything? Of course will the MF lens function, but at F/4, it is a completely different lens still.


Last edited by falconeye; 08-08-2013 at 02:23 AM.
08-09-2013, 11:20 AM   #242
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These are extremely sloppy (I left the Nikon at 6400 the whole time, and skipped 3200 with the Pentax) quickie tests of some of the theorized roundabouts between the two formats.

a. DOF, especially close up work.





In this application 6400 is not so good -- I would not choose to use it, but was too lazy to put a faster speed on it. F4 on the Pentax gets the lens in focus while f/5.6 doesn't on the Nikon.

b. Nikon AF is more consistent than Pentax, and quicker. Nikon did hunt less, and to my eye, with the 6400 noise, seems to have hit the dancer's face consistently. Pentax hunted a bit and there was one total miss (as usual attributable to a sloppy camera operator). Lenses are the DA 16-45 f/4 and 24-120 3.5-5.6 AF-D Nikkor; both older but quality lenses. Pentax has SR on, the Nikon lens is not VR.
c. At 6400 FF beats APS-C. Unfortunately I screwed up and didn't shoot a 3200 series; so I can only present a 1600 vs 6400 test.
d. DOF -- the FF at 5.6 has about a stop shallower DOF -- see below, I did manage to stop the Pentax down to f4.

These are 100% crops all









Same set, this time the full image. Overall point of view etc. Pentax metered much darker and warmer than Nikon (given the standard settings) and I had to do a ~ +1.3/1.4 adjustment with the center slider on levels.











So yeah, this proves beyond a doubt that most of the time it is the photographer's inattention and incompetence that is the deciding factor in image quality and proper usage of each format. It also points out some 'house flavor' in the two manufacturers' view of how to automate. And finally, originally I'd thought of pitting the DA 70 against the Ai 105/2.5 manual focus lens, but I simply got too lazy.
08-09-2013, 03:02 PM   #243
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Looks to me that even at ISO 6400 the Nikon produces a more appealing image and the colors are more correct than the Pentax.
08-11-2013, 09:10 PM   #244
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QuoteOriginally posted by DanWeso Quote
Looks to me that even at ISO 6400 the Nikon produces a more appealing image and the colors are more correct than the Pentax.
With my camera calibration workflow the differences in colour reproduction between my Canon,Nikon, Pentax and Leica are reduced to non-existant levels. The biggest differences I see are the differences in Dynamic range, noise handling characteristics and DOF with different sensor types which is mostly APS-C (Pentax Vs APS-H Leica M8.2 and FX format Canon 1DsMKIII, Nikon D3s and D4, The Leica M9 And Leica Monochrom*).

*I will point out that the Leica monochrom which has no bayer filter, colour profiling becomes completely redundant.

08-12-2013, 01:30 AM   #245
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Well I also see a lot off misfocus images, so this is not the worlds best test. White Balance is a different thing.
08-12-2013, 01:30 PM   #246
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QuoteOriginally posted by Digitalis Quote
If it was easy Zeiss would not have bothered making the 55mm f/1.4 T*. Bear in mind my comments are of a theoretical nature, I just figure it would be easier for Zeiss to use an existing Distagon lens design than come up with an entirely new one - but considering the history of Zeiss, they could have come up with a new design without difficulty.

The only way to empirically confirm whether this lens is an altered MEdium format lens is to simply use it on an ALPA FPS equipped with a MFDB with a 35mm lens adapter.
That's hardly empirical. Pentax had like a half dozen normal designs back in the early days, do you think you could tell which the modern designs are related to just from looking at some photographs taken with each?

"Empirical" would be tearing a lens down and figuring out the formula, and then comparing the optical effects of each element and group to the original.
08-12-2013, 04:43 PM   #247
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QuoteOriginally posted by RonHendriks1966 Quote
Well I also see a lot off misfocus images, so this is not the worlds best test. White Balance is a different thing.
QED.

Btw, there are some dust shadows on the K-30 (what a disaster! what a scandal!)
08-12-2013, 04:49 PM - 1 Like   #248
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By the way, this sort of thing is as true today as back in the 70s



08-12-2013, 05:26 PM   #249
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QuoteOriginally posted by Paul MaudDib Quote
The only way to empirically confirm whether this lens is an altered MEdium format lens is to simply use it on an ALPA FPS equipped with a MFDB with a 35mm lens adapter.
QuoteOriginally posted by Paul MaudDib Quote
Empirical" would be tearing a lens down and figuring out the formula, and then comparing the optical effects of each element and group to the original.

Incorrect - using a Medium format sized sensor with the Zeiss 55mm f/1.4 would be a good test to see if this lens has an image circle bigger than 24X36mm - if it can cover a large sensor: then it confirms that it is basically a modified medium format lens. Most lens makers have lens schematic diagrams that can be referenced, you really don't need to pull a lens to pieces to understand its optical design.
08-12-2013, 05:48 PM   #250
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QuoteOriginally posted by Digitalis Quote
Incorrect - using a Medium format sized sensor with the Zeiss 55mm f/1.4 would be a good test to see if this lens has an image circle bigger than 24X36mm - if it can cover a large sensor: then it confirms that it is basically a modified medium format lens. Most lens makers have lens schematic diagrams that can be referenced, you really don't need to pull a lens to pieces to understand its optical design.
False. For example, the Pentax 35mm f/3.5 covers nearly 55 millimeters of image circle, as does any shift lens for the 35mm format (if not mechanically vignetted to avoid reflection) The way a superfast MF-related lens would probably be constructed is the addition of a telecompressor (see: Olympus 35-100 f2.0, and probably both of Sigma's new superfast zooms), which would result in a reduced image circle, so your test is indicative neither way.

I doubt whatever it is will be related to the Distagon wide angle lens formula though. f/1.4 is super, super fast for something that wide. f/4 was normal for that design, so you're talking about picking up 3 stops of speed while maintaining Zeiss sharpness across the center 1/3 of your image circle. I don't think that's possible to be honest. If you used a telecompressor you would end up with a wide angle lens from the focal length reduction if it were a Distagon. One possibility might be something along the lines of a P67 105/2.4 with a telecompressor.

Using a diagram is just fine once it's available. Tearing it down is just another way of getting that.

Last edited by Paul MaudDib; 08-12-2013 at 05:54 PM.
08-12-2013, 06:12 PM   #251
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QuoteOriginally posted by Paul MaudDib Quote
I doubt whatever it is will be related to the Distagon wide angle lens formula though. f/1.4 is super, super fast for something that wide. f/4 was normal for that design, so you're talking about picking up 3 stops of speed while maintaining Zeiss sharpness across the center 1/3 of your image circle. I don't think that's possible to be honest.
As I have stated before my thoughts are merely theoretical - it isn't impossible to design a 55mm lens with a f/1.4 aperture that has outstanding optical charistaristics even at f/1.4 - if the imaging circle is big enough, no one will see how atrocious the corners really are on a format that is significantly smaller than the lens is capable of covering. For instance: the central 1/3rd of the imaging circle of the sigma 30mm f/1.4 is impressively sharp, even at f/1.4. However, the outlier portions of the imaging circle rapidly fall off to complete mush even at f/11 in the corners of the APS-C frame. I hear the sigma 30mm f/1.4 is a ripper of a lens on the micro 4/3 format - though it is a bit large for your typical 4/3 camera, a characteristic shared but the Zeiss 55mm f/1.4 - which just happens to be 2X bigger than any 55mm f1.4 lens ever made for the 35mm format...let me put it this way: from what I have seen, this lens is bigger than any standard 50mm f/1.4 lens I own ( and I own quite a few of them) doesn't that seem a tad suspicious to you?

Last edited by Digitalis; 08-12-2013 at 06:28 PM.
08-18-2013, 08:15 PM   #252
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If I wanted FF I wouldn't buy a pentax then. Sony for example has better FF lenses from CZ. The appeal of the pentax digital camera is the size and the features it packs. Having said that I have a medium format cameras that I shoot most of the import stuffs with. I would also appreciate all the legacy lenses you can use on a FF pentax camera. Something you can't do with canon.
08-20-2013, 11:53 AM   #253
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One big thing I would like about FF would be the change in focal lengths on the current limited lenses


Meaning the 77mm wouldn't be 115mm aps-c, the 31mm wouldn't be 46mm aps-c ...etc
08-21-2013, 06:17 AM   #254
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My humble prediction is that full frame may just be a passing fad in the history of digital photography. As sensors get better and smaller, there will simply be no real need for it. As someone who watched live and man first walked on the moon, the quality and capabilities of digital sensors has made enormous strides since. Back then, simply sweeping the sun with that camera would burn the sensor and render the camera useless.

No reason to think that the trend to improve sensors will not continue. I still think film is better, but this current generation of sensors is darned impressive.
08-21-2013, 07:04 AM   #255
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In the truly long term, you might be right. I'm thinking however that the market will become more polarized in the near term: phones eat the P&S segment, leaving room for enticing high-end compacts and evils... The APS-C SLR may feel a squeeze, as FF sensors become cheaper
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