50mm Test on a D700 (1)

Today I took the decision to test my Arsat 50mm 1.4 against 2 recent brand new Nikon lenses:
- the Nikkor AF-S 50mm f/1.4G,
- the Nikkor AF-S 24-70mm f/2.8G (at 50mm).



The 3 lenses have been tested on a Nikon D700, at 5 different apertures 1.4, 2, 2.8, 4, 5.6 (the 24-70 was obviously only tested at 3 last one). Those tests are absolutely not scientific, no chart were used. I only primary wanted to see the quality of the bokeh (out of focus rendering) of each lens but I found some surprises when testing the lenses.

The matrix metering of the D700 underexposes pictures of about 2/3 to 1 EV. (I've already seen this issue on a 135 AIS in some situations, this is normal because when using matrix metering on AI lenses, the focus point is not used to ponderate the global calculation of the exposure)

The Arsat renders the image with a strange green tonality compared to the 2 Nikkors, fortunately, the effet is very soft and can be canceled using white balance adjustement in post processing (or trust the auto white balance of the d700 that is from the 1.02 firmware version quite accurate).

The first surprising thing is that the arsat 50mm seems not to be a real 50mm. The angle of view seems larger with the Arsat than with the two nikkor, also out of focus rendering of point are rendered in more little circle by the arsat than the nikkor:


Other tests must be done when focusing at infinity to confirm this.

The second surprising thing is that the Arsat seems sharper than the two Nikkor (at least in the center). This also must be confirmed with other samples images. At 1.4 it shows less vignetting than the brand new, with a revised optical formula, Nikkor 50mm 1.4G but the contrast of the image is on the low side.

The better sharpness characteristic of the Arsat may be explained by the fact that the focal length is not really 50mm (at least not the 50mm of the two Nikkors), so the depth of field is wider at same aperture and focus setting, the sharpness appearing to be better.




By the way, the bokeh of the arsat of not really beautyful...

I will post a review comparing the Arsat 50 1.4 and the Nikkor 50 1.4G on the D700 in the next few weeks, with more "real" images that will draw a more definitive conclusion...