[Ben_Edict]

Hi all

I bought my K10D with the Pentax 18-55, and I find it a little soft. Compared to my manual focus f1.7 50mm the results seem, well, soft.

What comparable lens would you recommend?

I heard the 16-45 is better, which I guess is why it was a lot more expensive!

I'm considering the Sigma 24-135mm F2.8-4.5 Aspherical IF Lens and the equivalent Tamron.

Any thoughts on those from anyone?

As nobody else seems to use this Sigma I give you some thoughts on that. I bought the 24-135 for those occasions, when I would be too lazy to carry several lenses with me, kind of general purpose lens. I used it more often at the start, but somehow have forgotten about it now... It is not quite a superzoom, but as such it offers decent sharpness and contrast IF stepped down to f/8. This is generally the aperture I use (going down to f/11). Then the results are very acceptable.

But it is no replacement for a really high-quality lens. The focal lengthes it covers are useful and adequate for many occasions. The wide end could be wider, but that was something I accepted, when I bought it. Of course the wide max. aperture of f/2.8 is very good looking on paper - but it is hardly useable, especially as it goes down to 4.5 on the long end, where the higher aperture would be most useful.

So, what's my lesson? I would buy the lens again, for the purpose I bought it (family snapshots on the go). But if I need a high quality lens, I take another one. Oh, one thing: it has considerable "zoom creep". The lens always extends to full length, when I have the camera dangling on its strap.

regards
Ben

[peterfreeth]

Well that's an interesting suggestion ForrestGao, I had the shapness and contrast set to +1 so I pushed it up and you're right it did improve things a lot. I think actually the jpeg was slightly preferable to the RAW. It was on jpeg highest quality anyway.

I had the sharpness on +1 because on my old Lumix FZ20 things got very pointy if I pushed the sharpness up too much.

So now I have more experimenting to do!

Thanks again for all of your help, I really appreciate the advice and experiences you've all shared

Pete

Update: I've taken lots of test shots with different parameters and compared to the f1.7 50mm and here's what I found.

Certainly RAW was better than JPEG, and PEF was the better of the two - marginally better detail and less noise. Colour space; sRGB was better than Adobe, less noise again, or the noise was more consistently coloured giving a smoother image overall.

Set to PEF RAW and even on jpeg with sharpness on +2 and contrast on +1 the 18-55 actually did quite well, in fact I would say it was comparable to the 50mm, and that's with the 50mm at f8.

But given the extra hassle of RAW processing i.e. Paint Shop Pro 9 won't open either format even though it's supposed to, jpeg on the above settings was close enough to PEF to be good enough for everyday use.

So it looks like I don't need a new lens after all... but that Sigma 17-70 does look lovely... and I've written it on my shopping list now...!

Thanks again...