Carl Zeiss Jena Biotar 58mm f2 on NEX
Few years ago, when EVIL cameras were still in the labs, I was having a hard time trying to get some of the lenses to be used on the Canon DSLRs. Many of them were destroyed in the process, and some of the them were half dead, and this particular one, the Carl Zeiss Jena Biotar 5.8cm f2 had it's mounted cut away, in an attempt to mount it on the Canon and have infinity focus. Needless to say, I never succeeded. But, the NEX with the focus helicoid saves the day, again.
Butt gone -- Operation went bad
I went out at lunch time again today with the newly mounted Biotar, to the same place where I took the picture in my last blog entry, in an attempt to photograph the same thing. It didn't turn out the way I wanted, although I did take some similar pictures. The few I took at f2.8 did not have the focus point where it should, therefore can't really be compared. Below is one taken at f2 wide open. With a bit of sharpening, and resized, it's actually quite nice. There is no surprise that the Biotar has a nicer bokeh. This picture was taken closer than the EL-Nikkor. The original lens' focusing ring, plus the focusing helicoid which makes the lens able to focus much closer than other 50mm lenses, but it does seem to have a smaller magnification ratio than the EL-Nikkor.
Double Happiness -- NEX-5 & Carl Zeiss Biotar 5.8cm f2 @ f2. Click to see larger.
Finally, I took a 100% crop of a pictures taken at f2.8 from the Biotar, to the pictures taken yesterday by the EL-Nikkor, also at f2.8. Note that these two pictures were taken at different dates, and under different conditions and both hand held. So it's not scientific in anyway, but I think you can see the difference. The Biotar is one stop down from maximum, while the EL-Nikkor is wide open. I will put both lenses on tripod and try again later on.
Sharpness compared. Click to see the original 100% crop.
The slightly less sharp Biotar does not make it any less a lens, though. Sharpness is not everything. The EL-Nikkor is very contrasty, typical of Nikon lenses, just more so with this lens. The two lenses produce pictures with very different emotions. But, the Biotar can be very sharp from f4 on.
Playground -- NEX-5 & Biotar 5.8cm f2 @ f5.6 or f8. click to see larger.