A couple of months ago I made myself a Topcon UV adapter for my Sony NEX camera and over the last couple of days I've been trying out one of my Topcor UV lenses with it - the Topcon UV Topcor 28mm f/4.
The Topcon UV series are difficult to adapt to modern digital cameras because the aperture adjuster was fitted to the camera body rather than the lens - this is why I needed to make my own adapter rather than buying one.
The lens I selected for my first test was a Topcor 28mm f/4 prime lens because the 28 mm focal length becomes a good 'standard lens' focal length of 42 mm when the APS-C crop factor is applied. I took the combination with me on a morning walk for a couple of days earlier this week, and I've included the best of the pictures I took above.
For the most part, because the light is not very bright in November in the UK, the lens was set to its widest aperture which is f/4, but for the last shot looking into the Sun, I stopped the lens down to f/11. All the pictures were taken with pattern metering, Shutter priority and with auto ISO which enabled me to set both the shutter speed and the aperture and let the ISO 'float' and get the correct exposure.
The only problem I found with the adapter was that the lens focuses slightly past infinity, so I couldn't get to focus on subjects quite a close as I should have been able to. This is simply because I had to choose a basic adapter to modify which had a slightly shorter registration distance than the lens is designed for - however this is better than being the other way and unable to focus on infinity! The really good thing is that the aperture setting seems to work flawlessly, with the f/2.8 to f/4 settings having no effect, but the settings after that progressively stopping the lens down.
The pictures were shot in Raw and imported into Lightroom where I did a minimal amount of exposure correction and highlight / shadow balance before I exported them as Jpegs.
Although the pictures are not photographically very exciting, I do think they show the lens is capable of some quite nice results. I didn't do much adjustment in Lightroom, but I think the lens has some nice colour rendition and the pictures seem to be quite detailed. I suspect when it is stopped down by a couple of stops it would perform even better.
For my next experiment I will probably try my Topcor 135 mm f/4 lens to see how that performs.
