[mst]

http://www.opticallimits.com/nikon--nikkor-aps-c-lens-tests/477-zeisszf2128dx



One more D200-based review coming ...



-- Markus

[wojtt]

Markus, any chance for a FX test of this lens ? <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='' />

[Brightcolours]

[quote name='wojtt' timestamp='1295884454' post='5738']

Markus, any chance for a FX test of this lens ? <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='' />

[/quote]

Will an FF 135 format test do? <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/wink.gif' class='bbc_emoticon' alt='' />



http://www.opticallimits.com/canon_eos_ff/470-zeiss_zf_21_28_5d?start=1



Just take into consideration that due to a tonal curve difference the canon 5D mk II shows higher vignetting figures than the D3x does... for the rest, the test totally shows how well the 21mm f2.8 does on 135 format.

[mst]

[quote name='wojtt' timestamp='1295884454' post='5738']

Markus, any chance for a FX test of this lens ? <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='' />

[/quote]



Absolutely. And of course also on the D7000.



As Brightcolours has mentioned, Klaus tested the lens already on the 5D Mark II. The FX review will feature sample images in addition. And on the D3x the lens behaves slightly differently ... which simply provides some confirmation that you cannot directly compare reviews across different systems.



-- Markus

[wojtt]

Ok the Canon test gives an idea <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='' /> Time to start saving some funds <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/tongue.gif' class='bbc_emoticon' alt='' /> (again).. <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='' />

[Guest]

"Center and border sharpness is excellent at any aperture, from wide open down to f/11 (where diffraction begins to reduce resolution)."



I'm a bit puzzled, I have to say. I see this figure - f/11 - in every review of a sharp lens, and also, I see that the resolution starts dropping after f/4 or f/5.6 according to the MTF charts, in every review of a sharp lens. So, my interpretation is that excellent lenses are diffraction limited already by f/5.6 or f/8, not f/11, on 10 MP APS-C. Am I missing something?

[Brightcolours]

[quote name='BG_Home' timestamp='1295906337' post='5744']

"Center and border sharpness is excellent at any aperture, from wide open down to f/11 (where diffraction begins to reduce resolution)."



I'm a bit puzzled, I have to say. I see this figure - f/11 - in every review of a sharp lens, and also, I see that the resolution starts dropping after f/4 or f/5.6 according to the MTF charts, in every review of a sharp lens. So, my interpretation is that excellent lenses are diffraction limited already by f/5.6 or f/8, not f/11, on 10 MP APS-C. Am I missing something?

[/quote]

Things are not set in stone. Aperture placement for instance influences diffraction softening effects. So, yes, one can see trends regarding diffraction softening. But things can vary from lens design to lens design.



We anyway see the resolution go down slowly from f5.6 or so with this lens anyway, but I am guessing marcus means that after f11 teh resolution really takes a hit from diffraction.

[Guest]

Hi Markus nice test... but I have a little trouble to understand the policy behind the testing priority. The Zeiss has been tested with great results on Canon fullframe. Consequently it was clear that it wouldnt be a dog on a 10MP Nikon crop Camera. Thus anybody interested in that lens gains little to none from this additional test apart from thed iffernt absolute reslution/CA/vignetting/distortion numbers. On the other hand the 28-300 has not been tested at all yet, shouldnt the priority on that lens have been higher?

[Brightcolours]

[quote name='jenbenn' timestamp='1295949621' post='5747']

Hi Markus nice test... but I have a little trouble to understand the policy behind the testing priority. The Zeiss has been tested with great results on Canon fullframe. Consequently it was clear that it wouldnt be a dog on a 10MP Nikon crop Camera. Thus anybody interested in that lens gains little to none from this additional test apart from thed iffernt absolute reslution/CA/vignetting/distortion numbers. On the other hand the 28-300 has not been tested at all yet, shouldnt the priority on that lens have been higher?

[/quote]

Of course you are quite right, however that would mean that lenses only should be tested on full frame, unless they are APS-C only lenses.



Problem with that approach, though, is that you would have to explain time and time again to visitors how to read full frame tests with APS-C in mind. Because not everybody "gets" that.



Since photozone does both tests on APS-C and on FF, separate from eachother, testing the Zeiss 21mm f2.8 on APS-C is not all that strange. I am guessing there is more to the sequence of testing the lenses than just which lens people are waiting on the most.. For instance, when and for how long can the reviewer have access to a certain lens.



In case you can't wait on a test of the Nikon 28-300:

http://www.lenstip.com/index.php?test=obiektywu&test_ob=272

"Pros:

* wide and useful focal lengths range,

* good build quality,

* very good image quality in the frame centre,

* slight distortion on DX sensor,

* low astigmatism,

* vignetting on DX sensor not bothersome at all,

* efficient image stabilization,

* silent and relatively accurate autofocus.

Cons:

* weak image quality on the edge of DX and full frame as well,

* very high distortion on full frame,

* high chromatic aberration at longer focal lengths,

* significant coma in full frame corners,

* noticeable problems during work against bright light."



Not a great lens then, and certainly a bit strange for full frame, as the current size, weight and price of full frame cameras make those cameras be tools for advanced amateurs and professionals, while such a lens is more a tool for a "point and shoot" family shot photographer (the target group for the 18-200's on APS-C).



But, as the review also points out, the lens is not worse than the Nikon 70-300 VR in many areas.

[mst]

[quote name='BG_Home' timestamp='1295906337' post='5744']

Am I missing something?

[/quote]



No, you're not, and thanks for the hint. I tried to find different words than "diffraction kicking in" which has been used so often, but the phrase chosen was not the best choice.



Just changed it to "...from wide open down to f/11 (where diffraction already reduces resolution)." Better?



-- Markus