ChrisMak
Offline
• • •
Upload & Sell: Off
|
Steve Spencer wrote:
You probably had a very short adapter which would have benefitted from shimming. The Loxia 25 has a floating element and performance can be degraded if the adapter is too short. I have seen zero of the issues you describe with the Loxia 25 on the Z7, but I purposely picked an adapter that was as close to being thick enough that I could find. Not sure about the 35. It is the only Loxia I haven't owned. I have zero problems with the Loxia 21, 25, 50, or 85 with my Z7--although I replaced the Loxia 50 with the Voigtlander 50 f/1.2. I still have the 21, 25, and 85 and I have no problems with any of them.
Here is Jim Kasson's test of the Loxia 21 on the Z7. Note how well that does:
https://blog.kasson.com/nikon-z6-7/loxia-21-2-8-on-z7-and-sony-a7riii/
I don't think there is any inherent incompatibility of these lenses with the Z7. Note also Jim describes how the lens corrections are baked into the Sony RAW files. Part of what you are seeing may well be that the Nikon files don't have the baked in corrections and the Sony files do.
So, I would put the issue down to first potential issues with the adapter being too short (almost all are), and second issues with the baked in lens corrections. I don't think it is an incompatibility of the lenses with the camera....Show more →
I don't think it is the adapter, as I got the Schoten dumb adapter, which is the Techart adapter, but without the electronics. Also, I can júst focus past infinity, exactly the same as with the Sony A7RII.
I cannot post here, but I took a few exposure in daylight shooting through a sheet of neutral white thin photo paper. In Capture one, you can clearly see after white balancing, the shitft from neutral white in the centre to blueish in the corners and the frame edges. After generating a LCC correction profile, and applying it to real world images, the color desaturating effect of the blueish color cast is gone, and the image looks very close to normal.
The intesity of the effect is most apparent when shooting a white wall in a dimly lit, but not darkish room, at f2, you can see the wall going from greyish blue to warm white to greyish blue across the frame.
So if it is not the adapter, and all Loxia lenses exhibit this, what is most likely the cause? I am familiar with color casting of lenses on mirrorless since I went from dslr to the Sony A7r series. Especially skies can have heavy blue color casts, where they were much more towards natural grey, and Capture one makes this more obvious because they tend to exaggerate the blue channel quite a bit. But this happened only in a few images in very specific situations/lighting and when e.g. tilting the camera downwards to shoot a landscape from a mountain downwards. Phase one has a few learning videos on use of the LCC tool to correct for color casts in skies.
I mean to say that it has become much more present with mirrorless than it was with dslr, and I wonder what kind of sensor stack or mirrorless alignment tricks are used that have side effects.
Perhaps Zeiss supplied Sony with correction data for such a color cast, that is possible, or perhaps Sony generated this data, and since the correction is not there on the Nikon Z7, it suddenly becomes obvious. Luckily, the LCC tool in CO1 works very well, I just have to reshoot sometime with a perfectly neutral and even white semi transparent plate or sheet or something.
In the process though, I decided against the Voigtlander 50mm f2apo, and went the safe route with the Nikkor Z50mm f1.8S. I have to say that it is a fantastic lens. I will keep the Loxia 25mm though, as I am not sure of the Z24mm f1.8S regarding color and bokeh. The Loxia is also great in DX mode as a 37mm f2.8
|
that I have to always keep Z system around no matter what fancy gear come around in the future. 
