Pentax 17-45

Has anyone bought this lens or knows of a website that has tested it?

I'm thinking of selling my SMC Pentax-A f/2.8 20mm and buying the 17-45. Would I be disappointed at the wide end? The edge definition of the 20mm is great but I would like the zoom range.

Ooops! I meant 16-45!!!!

Malcolm,
The SMC-DA 16-45 is only for the *ist-D.
The build does not feel as rugged as earlier lenses, but it's still very well made and am sure it'll last.
That said, this is one stonking lens. I've had it now for a couple of months and this lens is wonderful!
Definition at 16mm is brilliant, almost no distortion. I've been taking crazy portraits at 16mm-20mm and they've all come out superbly clear. It's so good it's become my main lens, along with the 100mm f2.8 macro.
There are some small size shots here: http://www.ephotozine.com/user.cfm?user=16488
If you need anything higher res. I could email you something.

Matt

Thanks. That's just the sort of recommendation I was hoping for. I'll see what I can get for the 20mm and then make a purchase.

I know the 16-45 is intended to cover the sensor size of the *istD, but has anyone tried it on a 35mm body to see what sort of vignetting effect you get? It could be interesting and I'd be very interested to hear how it works and how it is affected by changing the aperture.

How would the Sigma 18-125 compare with the Pentax 16-45 in terms of image quality at the wide end? It is quite a bit cheaper with a slightly wider aperture. Has anyone experience of the new Sigma?

Hi Malcolm,
Don't know about the Sigma but if you are getting rid of the 20mm, I would be interested.
Regards
Kim

Don't know about the Sigma either... but what I do know is that since getting Pentax glass I don't want to use anything else! I have an old Sigma 70-300 which is definitely not in the same league.

John - I have already tried the 16-45 on the Z1. The vignetting is not as bad as I thought. However, since going digital the Provia in the Z1 has just sat there I'll run some tests off to finish the roll and let you know

Matt

Hi Kim

I have replied with a private message.

Malcolm

John,

I took some test images on the Z1 with the SMC-DA 16-45 at the weekend to finish off the Z1's final film (yes, it's going to have to go, the *istD is just too good!).

The results should be interesting. As soon as Fuji get them back, I'll scan and post them.

Through-the-viewfinder is interesting. 16mm shows vignetting, especially with the petal hood, but I think it's probably acceptable given the very wide nature. At 20mm there's hardly any vignetting.

I'll keep you posted...

Matt

Thanks for that, Matt, I'll look forward to seeing the results.

John,

I've received the Provia slide back, scanned it (rather hurridly) with an Nikon LS40, and posted a few 1024 pixel wide test images.
http://www.pbase.com/mattmatic/smc_da_test

Hopefully that should give a good idea of its performance on 35mm. To my mind, it's pretty good! Quality is wonderful, distortion is, well, what distortion!

Let me know if you need more info.
Matt

Thanks, Matt, those results are better than I thought they might be. There's no substitute for actual experiment!

Having started this thread I'd thought I'd let you know that I have bought the 16-45mm and am delighted with it.

I went to a wedding on Saturday and some of the shots are at
http://www.aaka92.ukgateway.net/Wedding/

I have one question. For the first 20 or so shots I had the camera set to the MTF program, and then realised that virtually every shot was being taken at full aperture (f/4). I switched to Green mode and things were then around f/8.

Today I've done a test of a landscape. Here are the results ...
Green - 1/640 at f/8
Hi Speed - 1/1600 at f/5.6
Depth - 1/125 at f/18
MTF - 1/2500 at f/4.5

Does the MTF setting sound right?

Malcolm,
I expect the MTF also varies with the focal length
The MTF values are programmed into the lens, and the camera reads them out (because it's the lens manufacturer that knows the MTF).
Matt