Has anyone done such a test yet? I know the uncompressed RAW is coming soon for the Sony, but I thought someone would have already done this comparison. Shocking if no one has.
Maybe you can make some samples of controlled light using highly reflective 3 dimensional polished objects? That would help a lot.
| Sony | P45+ |
| (http://echophoto.dnsalias.net/ekr/Articles/Shoots/BattleRoyal/DOF_1_20150921-_DSC2069.jpg) | (http://echophoto.dnsalias.net/ekr/Articles/Shoots/BattleRoyal/DOF_2_20150921-CF047005.jpg) |
Well the tea cup is a good start :-)
Although I know that was for other purpose. Troger had some helpful info, as well as ctz, and others. thanks Erik for continuing such tests.
I'm trying to open these files on my computer with CS6 or LR6...but here they look blurry :-/
I didn't know I could put a protection on my raw files...hmmm
The Sony file is out of focus...... Take a look at the wall behind it that shows clearly defined cracks. The Phase file has that wall out of focus and the flowers and pot in focus.
Victor
I have both a Leaf Credo 50mp back and the Sony A7Rll..... I also have an IQ180. I have shot the same scene with the A7Rll and Otus 55mm and the Leaf Credo 50mp/Alpa/Schneider 100mm Digitar. The focal lengths are very comparable and the lenses are both extremely sharp. I shoot the Schneider at f11 and the Otus at f5.6 and the differences are almost like splitting hairs. Any differences that I can see would have to be attributed to lens characteristics and, to me, neither one is better than the other.
Victor
Looks like the Sony shot has both camera shake AND focus behind the subject...
I can't stress enough that there is nothing in the 35mm world that can compare with either the Schneider Digitars Or Rody's.
I did consider camera shake, possible caused by image stabilisation, but the window behind the flowers is very sharp. So I would think that the Sony image has back focus, while I would say that the Hasselblad image has some front focus.
Just to say, I was quite careful shooting these images.
which one can actually mount on 35mm dSLM platforms, no ?
That's not the point.
A brief comment regarding both platforms..... I can't stress enough that there is nothing in the 35mm world that can compare with either the Schneider Digitars Or Rody's. The differences between the two platforms all boils down to lenses. At 100% pixels there is a visual difference between the my Otus and my Schneider Digitar. Even at just 1 f stop apart the differences remain. There is a clarity that exists with the digitar that is very pleasing. In print it would be almost impossible to see but it is there. Call it the MF look or whatever you want but when manufacturers finally start making slower lenses with very large image circles the gap will start to close.
Victor
Hi,
If you put two lenses of equal quality, say diffraction limited at f/5.6 on two cameras of different formats, the larger format will always win as long as we can use the optimum aperture, as magnification will be smaller.
DoF requirements may force smaller aperture on the larger format, so MTF would be lost to diffraction.
Lets see it this way, the image diameter on the Sony A7rII is 43 mm, while on the P45+ it is about 60 mm. So the A7rII needs to be magnified 60/43 = 1.40x compared the P45+. This essentially means that if we assume that the P45+ lens achieves 60% MTF at 40 lp/mm than the Sony lens would need to achieve 60% MTF at 56 lp/mm. Or we could guess that the lens on the A7rII would need to achieve 84 %MTF at 40 lp/mm. The Otus at optimum aperture would be somewhere there. So it would need an Otus to match a Planar 100/3.5 on a P45+ back, and that Otus should not be stopped down f/5.6.
Best regards
Erik
Hi,
If you put two lenses of equal quality, say diffraction limited at f/5.6 on two cameras of different formats, the larger format will always win as long as we can use the optimum aperture, as magnification will be smaller.
DoF requirements may force smaller aperture on the larger format, so MTF would be lost to diffraction.
Lets see it this way, the image diameter on the Sony A7rII is 43 mm, while on the P45+ it is about 60 mm. So the A7rII needs to be magnified 60/43 = 1.40x compared the P45+. This essentially means that if we assume that the P45+ lens achieves 60% MTF at 40 lp/mm than the Sony lens would need to achieve 60% MTF at 56 lp/mm. Or we could guess that the lens on the A7rII would need to achieve 84 %MTF at 40 lp/mm. The Otus at optimum aperture would be somewhere there. So it would need an Otus to match a Planar 100/3.5 on a P45+ back, and that Otus should not be stopped down f/5.6.
Best regards
Erik
Erik, I'm not so sure you're right. MTF 50 is an accepted single-number way of measuring, but you cannot scale the MTFs around so easily as the curve is not the same on all lenses. By analogy with circuits, some lenses will drop at I guess 6db per octave or whatever at the frequency you are at, some are still flat etc. Also, MTF gives you the native (hopefully) (Imax-Imin)/(Imax+Imin) at that spatial frequency, but afterwards you can postprocess ...
Mixing reasoning in linear spatial and Fourier db spaces is not always a good idea, at least it seems counterintutive to me with my very rudimentary understanding of mathematics :)
Edmund
And you can be sure that there are no internal reflections caused by an adapter or different camera than the Otus was designed for?
Erik...... this isn't a matter of sharpness. I decided on an image where I could easily move either camera so that both matched each other in the horizontal plane. They are both very sharp. However the Otus image shows a slight ghosting (for lack of a better explanation). This ghosting has appeared with any 35mm lens I have tried from Leica to Zeiss to Nikon.
I believe Victor explained his reasoning clear enough. I've done a similar test and find the problem to be one of clarity. I was able to bump the clarity slider to 100% (for the Otus) and then move other sliders (sharpening, luminous noise, etc.) around and was able to realize about 98% of the MF (Alpa/Rodenstock/50 mp back) combo. Then you have to deal with the color issues of DSLR versus MF >:(.
Victor,
This is interesting. I have been using both Otus extensively on a D810 and have never noticed any ghosting, but I am unsure what you are exactly refering to.
Would you are some examples of that phenomenon? That would help me understand whethet I have been overlooking something.
Thanks.
Cheers,
Bernard
I believe Victor explained his reasoning clear enough. I've done a similar test and find the problem to be one of clarity. I was able to bump the clarity slider to 100% (for the Otus) and then move other sliders (sharpening, luminous noise, etc.) around and was able to realize about 98% of the MF (Alpa/Rodenstock/50 mp back) combo.
Then you have to deal with the color issues of DSLR versus MF >:(.
Erik, I'm not so sure you're right. MTF 50 is an accepted single-number way of measuring, but you cannot scale the MTFs around so easily as the curve is not the same on all lenses. By analogy with circuits, some lenses will drop at I guess 6db per octave or whatever at the frequency you are at, some are still flat etc.Lets see it this way, the image diameter on the Sony A7rII is 43 mm, while on the P45+ it is about 60 mm. So the A7rII needs to be magnified 60/43 = 1.40x compared the P45+. This essentially means that if we assume that the P45+ lens achieves 60% MTF at 40 lp/mm than the Sony lens would need to achieve 60% MTF at 56 lp/mm.
Victor,
This is interesting. I have been using both Otus extensively on a D810 and have never noticed any ghosting, but I am unsure what you are exactly refering to.
Cheers,
Bernard
Bernard..... a few brief comments on the legendary Zeiss QC. This is my third copy of the Otus 55mm.... the first two were out of alignment. Even this one is slightly skewed but probably the best of the bunch. I also purchased the Otus 85mm. The first thing I do with any lens is shoot a chart..... it doesn't tell everything but its a good starting point. I couldn't believe what I was seeing with the 85mm. An entire top edge out of focus, corners that were out of wack, one sharp another blured. I have found that all of these anomalies extend to everyday shooting. All of this for an outlay of $4500.00. I owned that lens for 2 hours, packed it up and sent it back. I was so pissed/disappointed that I didn't even want a replacement..... just a refund. This experience goes hand in hand with my quest for a 135mm. I had two copies, one right after another with both showing the same severe alignment issues. Needless to say I don't own a Zeiss 135mm. If they want the big bucks then they should provide perfect lenses - or at least a lot better than I was presented with.
Victor