8 out of 10 points and recommendedGreat Value, Great Image QualityNot a very fast lens
I got the Pentax K2000 Camera that comes with the cheap version of the Pentax DA 18-55mm f/3.5-5.6 AL. I say cheap because it uses the same glass but with a cheaper construction. Plastic mount and no lens hood.reviewed July 6th, 2009 (purchased for $90)
Pentax DA 18-55mm f/3.5-5.6 AL II upgrades in the following areas:
1) Better overall construction, metal mount
2) Hood is included
3) You get focus measurements on the focus ring for the manual "Quick-Shift Focus System"
4) Less Vignetting compared to Pentax DA 18-55mm f/3.5-5.6 AL (But still there wide open)
5) Sharper on center and boders compared to the Pentax DA 18-55mm f/3.5-5.6 AL on my Pentax K2000
Problems is still has
1) Has the very same Distortions as the Pentax DA 18-55mm f/3.5-5.6 AL common to zoom lenses. The distortion still makes the corners soft at 18mm.
2) Same speed (f/ stops) across the lens
3) Same 18 - 55mm short zoom range
4) Visible vignetting at 18mm wide open at f/3.5-4.5 and a little at long end 55mm wide open f/5.6. Better than before but still these. Goes away as you close down.
Pentax DA 18-55mm f/3.5-5.6 AL vs Pentax DA 18-55mm f/3.5-5.6 AL II
at 18mm F/3.5: The Pentax DA 18-55mm f/3.5-5.6 AL II has more contrast, sharpness, especially on the corners, but it is still soft. At F/5.6 both lenses improve in sharpness but the Pentax DA 18-55mm f/3.5-5.6 AL II stays ahead. At F/8 both are almost equally sharp at center but the The Pentax DA 18-55mm f/3.5-5.6 AL II still has sharper corners. The Pentax DA 18-55mm f/3.5-5.6 AL II clearly has less Vignetting at all apertures at 18mm.
at 35mm F/4.5: The Pentax DA 18-55mm f/3.5-5.6 AL II has more contrast, sharpness, especially on the corners. At F/5.6 both lenses improve in sharpness but the Pentax DA 18-55mm f/3.5-5.6 AL II stays ahead. At F/8 the The Pentax DA 18-55mm f/3.5-5.6 AL II is almost in a virtual tie with the Pentax DA 18-55mm f/3.5-5.6 AL, the closest I find both lenses to each other and the sweet spot for both lenses. The The Pentax DA 18-55mm f/3.5-5.6 AL II clearly has less Vignetting at F/4.5-6.3 apertures at 35mm.
at 55mm F/5.6.5: The Pentax DA 18-55mm f/3.5-5.6 AL is soft. On the other hand the the Pentax DA 18-55mm f/3.5-5.6 AL II is sharper and has a nicer bokeh (out-of-focus blur). At F/8 the The Pentax DA 18-55mm f/3.5-5.6 AL II clearly has a sharper and brighter image. The Pentax DA 18-55mm f/3.5-5.6 AL II clearly has less corner Vignetting at all apertures at 55mm.
In this version II of the lens it is very similar to the old Pentax 16-45mm f/4.0 SMC PDA ED AL wide angle lens in image quality and speed. The Pentax 16-45mm f/4.0 SMC PDA ED AL has less vignetting but the Pentax DA 18-55mm f/3.5-5.6 AL II has less chromatic aberrations. Sharpness is not that much different at the long end with both lenses with the Pentax 16-45mm f/4.0 SMC PDA ED AL having better center sharpness at the short end.
So the question becomes, is it worth the money? I got mine for $90.00 so to me it was a decent price and a decent upgrade. In the end I find the Pentax DA 18-55mm f/3.5-5.6 AL II a good buy. It is small, light and is nice to walk around.
8 out of 10 points and recommendedPrice, image quality, colorsquality control, soft at f/2.8
First let me say my first copy of this lens was totally bad, soft at just about every everything under f/8.0. My second copy behaves very similar to the review copy from SLRgear.reviewed July 25th, 2009 (purchased for $400)
I'm using this lens on A Pentax K2000 (K-m in Japan), that has the same sensor as the Pentax K200. I have several other lens but my best lens is Pentax SMC-FA 50mm f/1.4 and I define sharpness, color and contrast in light of the quality of this lens (one of the better 50mm primes).
at f/2.8 it is soft and at center or corners depending on the focal length. Still, testing also shows potential for smaller images after sharpening, especially at the shorter end. My Pentax SMC-FA 50mm f/1.4 gives much better images at f/2.8.
at f/4.0 everything improves a great deal, especially center sharpness but there are still signs of some corner softness at some focal lengths. My Pentax SMC-FA 50mm f/1.4 is still better at f/4.0.
at f/5.6 this lens can go "mano a mano" with my Pentax SMC-FA 50mm f/1.4 and at times I think the Tamron does better. I suspect that both lenses are exceeding the resolution of the camera sensor at this aperture. The fact that this quality at this aperture is so consistent across the full focal length gives the Tamron many points.
at f/8 the lens acts a little strange. At some longer focal lengths it is as almost as good as when used at f/5.6 while in the shorter end we get a significant lost in quality. Totally usable and still good at f/8 but the lost of quality is unexpected, a little better than f/4.0 at center but no corner softness on the short end.
at the longer end sharpness is excellent from f/5.6 - f/7.1, very good from f/8-f/11 and still good from f/13-f/16 with little distortion to talk about.
Macro is very good at 75mm f/8.
My biggest issue with the lens are as follows: my first copy was bad and too many people write similar experiences. That is not good quality control. My second issue is that from an expectations point of view, at least on my Pentax K2000 camera, the lens seems like a good constant f/4 lens with a f/2.8 in case of emergencies. I would avoid using the f/2.8 aperture if possible (remember, I have a Pentax SMC-FA 50mm f/1.4 lens and used to very good quality at f/2.8). Now, since I paid $400 for the lens and that is more or less what Sigma would charge for a similar lens and 2/3's of what Pentax would charge for their Pentax SMC-DA 17-70mm f/4 AL SDM (that is a little soft at the long end) this is a good buy. Were it not for the quality control issues getting this lens would be a simple "YES". As it stands, I'm like, think about it and be ready to test and return if necessary. If you get a good copy you will find it a good value.
Update: After some more testing in real life the f/2.8 aperture setting has done well. The photos are at least average and usable after sharpening so I'm giving this lens a 9 in image quality.