The second shot appears to have a blue hotspot which I typically get in some situations with some optics. The hotspot is only seen on dark things.
I have experienced this with, Zeiss ZF 50/2.0macro,HC35/3.5 & Nikkor 85PC sofar but I doubt these are the only ones that show this. I have samples of this phenomena with dark clothing, shoes & other accessories as well as indoor shots of stuff like showrooms. It happens on certain distances, especially close distance.
In my case most of this occurred with shots on white backgrounds. I opened a case with Zeiss, they acknowledged the problem eventually and told me it was due to the optically design of the that specific lens.
I opened a case for the Nikkor 85PC as well, I tried various samples and all of them exhibited the same kind of optical phenomena.
You might experience the same type of thing. Try shooting a dark object on white also on f8 and see if you get the same thing.
Color of the hotspots seemed to vary with either lenscoating or IR filter color of the back in use, not sure about that.
This is the reply I got from Zeiss on my questions about this:
"we did several tests to evaluate the problem. The Makro Planar T* 2/50 ZF seems to be susceptible for the occurence of such a bluish reflection at close distances under such lighting conditions because of its optical design. The blue spot is only visible on dark subjects - on white subjects the difference in hue and saturation is too small to get visible.
The only way to avoid this problem is to take image with less of the bright white background or to use another lens. The Macro Planar T* 2/100 ZF does not produce any blue spot under the same lighting conditions. "
I got similar replies from Nikon but that was longer ago so I can't find these that quickly (and they are probably in Dutch anyway).
