DA* 16-50, got mine some days ago and now I am confused or even bewildered. You ask why...
Well, I have made some experiments because weather has been too dull for real photographing. And my findings make me nervous.
1. Focusing is weird.. sometimes it is right on but mostly way off at wide end... very inconsistent.. I cant find situations where it always fails or where it always works perfectly.
2. The wide end at 16mm is soft. And I mean really soft. But what makes me rattle: it seems that sometimes it is quite good, but usually ... soft.
I made some tests with tripod and newspaper, distance 2 meters, manual focusing, sensor plane parallel with wall (and newspaper) etc. I know quite well common parameters in this kind of testing. I concentrated only to center part of the picture because if it isn't good then it doesn't matter what kind the corners are. And my findings are:
16mm 2.8: very very soft
16mm 4. still very soft, some enhancement visible
16mm 5.6: quite good
16mm 8 good/very good
16mm 11 good/very good
20mm 2.8: quite good
20mm 4. very good
20mm 5.6 very good
etc.
The lens is very sharp and contrasty at all other focal lengths and apertures but in the 16mm at f2.8 and f:4 are totally unacceptable, they cant be used at all....
I made same tests with my DA 16-45 and it wins hands down at 16mm until f:8. At f:5.6 they seems to be equal. At all other focal lengths the DA* seems to be better.
Focusing is a joke at wide end. I don't know if these problems are somehow combined, but it works much better at longer end. Actually it is quite good there.
I am really happy not have been sold my DA 16-45 yet.
Obviously I have to return this piece of junk. I don't need 20-50/2.8 lens because I already have very good copy of Tamron 28-75/2.8.
Do I have any hope to get good copy or do I just try to claim my money back? I suspect that there is no unsold DA* 16-50:s in the shelfs here in Finland....
Edit: some results more: it seems that at shorter distances, less than one meter, results are better. I took some pictures at my son at the distance of ~1m, 16mm, 2.8 and 4.0. Those appeared to be at the acceptable level, not sharp, but good enough. Then I asked him to go to the distance of two meters.... soft, soft and soft. It doesn't matter if AF or MF is used. I even chanced focusing screen to Kaz Eye micro prism/split screen one.... it doesn't help. When picture seems to be perfectly focused, picture still is soft.
I also made some quick and dirty comparisons at 28mm focal length between DA* and my Tamron 28-75... you do not like this, but less than 1/2 price Tamron seems to be as good as DA*....
I have considered myself as an true believer (or an fanboy as others might say), but this puts my belief to real test