Now the weak point distortion at the 18mm mark, this might have DK crying into his Apple keyboard (or maybe not!)
For some reason in camera corrections work even though I didn't see the lens listed in the firmware updates
Moustache type distortion so not so easy to correct though it might not be a problem for some shots
Moving up the zoom range there is some fade in the extreme corners though it's nowhere near as bad as I expected or saw in Kurt Munger's review (which looked awful) this isn't so bad but stopping down a bit will help here.
A summary
-Central sharpness is very good across the focal range usable at max aperture at all focal lengths, in some ways super sharp quite impressive it has real bite
-At 18mm f3.5 even the corners are quite good very sharp in the central region
-Vignetting is there at times but it's not a huge problem at any focal range (less than the Nikkor 18-105mm for example)
-Distortion wide end, well it's a guy in a green suit emerging for Sherwood Forest folks, but similar to the Nikkor I used, tele end distortion isn't really bad at all much better than the 18-105mm VR at the top end of the zoom but noted more pincushion around 50mm
- Some fade in extreme corners moving up the zoom range, but by much better here than I expected
- CA well controlled only a few cases where I saw it and it was not huge by any means
- AF is quick and accuracy was good using it in real world situations, the SAM motor is "quieter" than previous SAM motors (by a fair bit) but it is not SSM, USM/AF-S silent or as quiet (you will hear it on video but maybe not if ambient sounds are present)
- Build is surprisingly good, decent plastics, metal (aluminium mount), smooth zoom action, zoom lock at 18mm, full time DMF with the MF ring (which is mechanical), decent hood overall very pleasing build wise.
- Close focus is about average for a lens of this type 1:4 ok for a close up but that's it
- It's a bit more compact than the Nikkor size wise and uses a smaller 62mm filter and the AF is notably quicker
- Blur factor, well I found it pleasing overall quite good and better than other comparable lenses I've used (the Nikon was ok here but not as nice IMO) Though I don't feel folks buy a lens like this for that de-focus effect, you can of course put a background out well enough if it's not too close.
- Good up/down rather than left/right AF/MF switch (just feels easier to get to and use)
- Has the usual dust magnet Sony fine ribs on the zoom/MF ring
I'm not usually impressed with lenses like this or superzooms, but in this case I was impressed with the lens which is really very sharp and usable at all focal lengths. There are no obvious weak focal lengths (unlike the 18-250/270mm superzooms) but you pay a price at times with distortion
In some cases the central sharpness was near quite stunning with excellent contrast and resolution (a real surprise here)
Compared to the Pentax 18-135mm it bends it over it's knee and spanks it's rear end red raw on sharpness and optics (I was really quite disappointed with the Pentax when I tried it not very sharp, bad at the tele end even stopped down and monster CA too)
The Nikkor 18-105mm, I liked that lens and had a good copy of it. The build of the Sony is much better, and the AF certainly faster. Optics wise the Sony has the advantage here (which surprised me) the Nikkor is good sharpness, the Sony just has the bite/contrast that gives it the edge IMO. Only the quieter AF on the Nikkor wins out. The plastic mount on the Nikkor is well known as a weak spot
I have used Canon 18-135mm (but not the new STM version) The Sony is far superior on an optical level in every way bar possibly distortion. The Canon was quite poor in the corners across much of it's focal range even stopped down. Not a patch on the Sony sharpness wise, and with some CA problems too. Another knee spanking for this lens.
Again I'm finding the real world use of this lens is far removed from Kurt's review he must have had a real turkey copy of this lens
Now it could be argued I didn't actually pay for the lens, but then if I thought it was rubbish I'd simply sell it and tell you it was a joke. I'm actually stunned it's as good as this overall.
Verdict 8/10 for me
If you want a good travel zoom this is well worth checking out. Asking price is not bad about £230
I've seen some pretty good kit deals with this, do yourself a favour and pay the bit extra to get this v the 18-55mm SAM this is way sharper and a much better lens. (and yes much superior v the 18-70mm DT even a good copy)
Obviously it's not a fast lens, so bag a fast compact prime for travel and you're good to go. It does not obviously replace a 17-50mm f2.8 but it might make a useful addition to your bag. It worked fine for AF on the KM5d's I have no issues to report.
I have to say I really like the lens overall despite my initial scepticism it has turned out to be a quite impressive lens esp v the other makers Sony in most ways have nailed this one so good job on that!
Keeper..