Vega-5U 105/4 is Medium Format Enlarger Lens (Вега-5У).
With no focus helicoil, this lens must be used on extension tubes or a bellows and an M42 adapter. Imprefer a bellows for much quicker operation. Effective previews with stop down metering is needed on the camera body. The Sony a65 body is ideal for using these legacy lenses as it has the necessary controls to focus, creative modes, video, image stabilization and adjust exposure in live mode.
The medium format (6X6, 6X7, 6X9 with120/220 film) covering power of this flat field lenses all but eliminates soft corners and other aberrations on an APS-C sensor - common issues to modern 'taking' lenses with minimum covering power. Contrast is neutral and sharpness is very good from one stop down, although the image softens slightly with infinity subjects.
As a closeup and macro lens, the Vega works nicely. Composition with the bellows and an external LCD display is fairly quick and quite versatile, given the magnification range this setup allows - from infinity to 1:1 and more. The peaking feature on the Sony a65 gets initial focus accomplished easily. Using the focus magnifier to finalize focus takes another few seconds. Test shots can be taken and reviewed to determine ideal DOF focus points in closeup/macro situations to capture preferred areas of an image.
Lens speed limitations become evident during late afternoon hours but for well saturated images the Vega shoots easily in open shade and daylight at low ISO's. There is no evidence of flare or CA and bokeh is creamy smooth wide open. IQ is consistent at all apertures with DOF as the primary adjustment for control of any composition considerations.
Posted by: Brian Patterson Date of publication: 05.05.2016