Originally posted by george2013 How are those Takumars coping with high contrast fully open? I had bad experience with some old lenses showing noticeable hallos and glow.
The earlier series of Tak lenses, all before multi coated in the name, were single coated lenses. I have noticed that they do suffer challenges with high contrast edges where one side has a very bright light, such as light sources or sun. I live with it and usually enjoy it as part of the aesthetic of these lenses. I do not notice the challenge unless there is a very bright source on one side of the edge. A chessboard in normal light is high contrast but does not push the effect.
This was the effect which pushed th search for improved performance, which led to the multicoating treatment. I only have two multicoated ones (35/3.5 and 200) and have not usesd either much, so have not firm opinion.
Using a lens hood helps this effect.
There is another effect I noticed. The wide angle lenses all have small rear elements, which means there is a large rear surface. SuperTak and later lenses had this surface painted in the matte finsh for non-reflectiviyy. The only Auto Tak I have used (35/3.5) had a very smooth surface finished in a glossy finish (anodised?). This must have been acceptable in film, but in DSLR (K100DS at least) there can be reflection from the sensor (which is basically glass with reflective bits on it) rather than the less reflective emulsion of film. The frlection in the auto tak then reflects off the back of the lens and results in a generalised fogginess leading to poor contrast, not quite the effect you describe. The effect was less in dull light, but still noticable. I normally use these lenses with Av mode, and +1.3EV to get consistent good exposure. The AutoTak demanded to be set at +0.3 or ).6 to work reasonably, but that only disguised the effect, did not remove it.
I have the 55/1.8 and 55/2, both STak. The f1.8 is in better condition, and is nicer to use. The f2 was my first normal m42 lens, and got me hooked. I bought a cheap one just to find out how it would go, technically, could I get it to work OK. I had to open the f2 to remove some adhere muck on an inner surface. It is very easy to remove the glass for cleaning, and designed so it can only be assembled correctly.