Boris, some remarks to add to your confusion ;-)
o It seems that lenses from Canon/Nikon and the likes are often closer to what test procedures ask from a lens (contrast/sharpness), so Pentax lenses often get less good results - at least it looks like that in my part of the world and yes, it could well be that this is only so because Pentax advertises less in the magazines that publish the tests. We don't know what Pentax is thinking. If they really have a different take on what a good lens is, a more holistic approach instead of a 'scientific' one, based on measured sharpness and contrast, then they are certainly not good at 'selling' it. o We cannot be sceptical enough regarding our own perceptions and "test procedures". I believe it is plain impossible to say anything about a lens based on a set of 4x6 prints. Even if you look at slides you need to always be aware that the loupe or the projector lens also is part of what you see. If you try to compare pictures taken of identical subjects you still have a whole bunch of issues that may make the results worthless. You just don't know whether somebody claiming a lens to be 'less sharp' in reality is talking about his shaky tripod... A person may also just not telling the truth - half of what is written on the internet is wrong. o We don't know if and how much sample variation there is. I personally have not been able to show much of this when comparing lenses of the same series but a) I do not have a testing laboratory and b) it is certainly possible the the particular lens that the owner claims to be "less good" is a lens that deviates fom the rest. I personally have concluded to stop 'testing' more or less. I have my personal lens favourites (my M 4/20, my FA 24-90, my M 2/35 my 3,5/35-105 stopped down) and I would go as far as recommending to give any of these a try, but no further. Sven Zitat von Boris Liberman <[EMAIL PROTECTED]>: > Hi! > > It would appear from the most recent talk that Sharpness is more or > less __the__ most important characteristic of the lens. However, from > previous talks it has become my understanding that Pentax do not > optimize their lenses specially for sharpness (except may be macro > lenses and such). Pentax, AFAIU, optimize their lenses for plasticity, > or overall smoothness of the picture. > > OTOH, Nikon are known for having their lenses tack sharp all over the > frame. At least this is what I have accumulated in my small knowledge > bag so far. > > Please unconfuse me - why all this talk about sharpness? I do realize > that for digital lenses should be very sharp. Or at least, it would be > a reasonable thing - to want one's lenses to be sharp. But sharpness > is not all, right? > > Most recently I've sold my Soligor C/D 70-222/3.5 lens in favor of my > Pentax SMC F 70-210/4.0-5.6. It could very well be that Soligor is > sharper on some apertures. It is faster too. However it has rather > ugly bokeh - at least to my taste, and general zoomish taste on the > pictures I've been able to take with it. Pentax lens however is very > smooth, very 3D, very pleasant. It is also lighter, has AF and is of > course fully compatible with my MZ-6's electronics. It also allows for > use of built-in flash at least for some of the focal distances. But > this is already tech-talk. > > Still, why to be so aware of sharpness? I mean, if one wants > sharpness, perhaps one should look for 3rd party lenses specially > optimized for sharpness. > > Please unconfuse me. > > Thanks. > > Boris > >
