Contax (actually Kiev in here) – Sony FE adapter with Helios-103 53mm f1.8 lens
I bought cheaper version Russian adapter, and the lens come together as a bundle, WoW!
Mirrorless is ultimate camera platform which doesn’t require range finder, reflection mirror or whatsoever redundant mechanism from 20C. It just read the image from the sensor directly. Simple & no room for error…
Zeiss Ikon design has its own character, over-engineering…Contax RF is not an exception. Only standard lens, 50mm connects to inner bayonet & all others goes to outer bayonet. Why they didn’t make simple and easy, 1 bayonet to fit all? (I really have no idea what would be benefit for having 2 bayonet)
Kiev lens is basically the cron of Carl Zeiss Jena lenses, Jupiter-3 to Sonnar 50mm f1.5 and Jupiter-8 to Sonnar 50mm f2.0. I have no information when 53mm f1.8 released for Kiev RF, but I guess this is an effort to make their own design later part of Kiev production.
Typical old optics characteristic, swirly background and edge bright bubbles which caused by excessive aberrations. Aesthetically it is not necessarily bad compare to perfect Gaussian ring…
Widest aperture, f1.8
1.5 stop down to f2.8
f1.8 Color version
Definition of center area is OK (pretty much acceptable) but middle and outer edge resolution fall off abruptly. And there is slight veiling glare on entire image field.
This is not always bad because it can add unique mood on Portraits. Slight veiling glare will smoothen skin tone, and blurred surrounding brings high attention to center subject, a typical portrait technique in old days. – In other words, to be fair, it is not suitable for other applications…
With modern lenses, we have to rely on Photoshop to make nice blurred image. Image quality improved significantly if 1 stop (f2.5) down. Note veiling glare also removed.
f2.5 BW version
It is soft & pastel tone comparing to original scene or modern lens output. Again, it is the characteristics of old lens, single coated or non coated. At right-down side, bottles got unusual blur caused by aberration, which is distinctive for Helios-103.
Mitakon 50mm f0.95 example (at f0.95)
Edge resolution at wide open
Center crop, hint of color aberration exist
Edge crop – can see serious aberrations including color fringe.
Landscape example in BW
Does edge resolution issue caused by field of curvature or aberration?
If aerial image is bended slightly, it is called as Field of Curvature. With Sony A7m2, I can select corner and enlarge to make focus on that area. If image improved, it means the lens has big field of curvature. If not improved, it means aberration is excessive. As the end, I can not make any better edge image, no matter focus shifted to front or back.
Landscape at f5.6
When wide open, Helios-103 delivers good image at center but abruptly degraded at middle / outer area which is similiar to old ‘portrait lens’. If utilize this character proactively, it could deliver unique portraits like antique photos. When stop down f2.5 or below, image quality improved a lot, and color saturation increased slightly too due to veiling glare on full image removed. But it still remains in the soft-pastel color side. It may be not a good choice for general purpose lens. But it can deliver unique characteristic in Portraits.