I like Sun lenses, they were one of the few companies to make their own
lenses in a time when many of the popular brands were just distributors putting
their name on other companies designs. The company started off some time soon
after the second world war rising from the ashes of the K.O.L lens company. They
initially made lenses for the Leica screw mount and one of the appealing
qualities of their lenses is that they continued to make lenses that were
aesthetically pleasing in a time when other brands were becoming a sea of dull
blackness. The company appears to have ceased the production of 35mm lenses in
the late 80's but the company still seems to exist as a manufacturer of
industrial lenses, on their website they claim to have began operating in the
late 80's but had a past in the 35mm lens industry so there is surely a
connection but how deep or shallow it is I have no idea.
The sharpness wide open is not bad in the centre but poor at the edges, unfortunately the edges don't really come up to scratch until F/8-F/11 but I find myself using this aperture a lot with wider angle lenses anyway. The lens also makes a fairly good portrait lens on my Olympus E-410 where it has a 56mm equivalent focal length, in this situation I can use the lens wide open because the subject is more often than not at the centre of the frame.
Where this optics strengths lay are no doubt in the colour and contrast department, there is a very appealing warmth and enthusiasm to the colours this lens produces and the contrast is gives a decent pop that almost makes up for the lack or resolution at wider apertures.
The bokeh is interesting in that it is very smooth wide open but at smaller apertures has a strange almost ring shaped appearance on highlights, almost like a mirror lens. I like it personally but then again I like mirror lens bokeh so I'm a Judas in any case!
There follows some samples which can be clicked on to see a larger version.