Pentax smc DA 17-70 mm f/4.0 AL [IF] SDM review - Summary

Have you rated your lenses yet?

Pentax smc DA 17-70 mm f/4.0 AL [IF] SDM

10 June 2009

Arkadiusz Olech

11. Summary

Pros:

universal focal lengts range and decent fastness,
solid body,
very good frame centre picture quality,
good frame corner quality at 17 mm and more,
good chromatic aberration correction,
the lowest vignetting in its class,
high transmission and good colour reproduction,
quick, silent and efficient autofocus system.

Cons:

the manual focus ring moves too easy and is too small,
weak against the bright light performance,
too little frame corner resolution at 17 mm.

Two questions, this test should give answers to, concern the cost-effectiveness of changing the kit lens 18-55 mm for Pentax 17-70 mm and a choice between the Pentax and the Sigma with the same focal length range. To tell you the truth non of these answers can be straight. When we replace the kit lens with the Pentax 17-70 mm we get a biger focal length range, a faster lens and a better autofocus. Is it worth the pain? It’s difficult to say - not because of the weaknesses of the Pentax 17-70 mm performance, we couldn’t say there were many of them, but because of the good quality of the cheaper Pentax kit lens, given almost for free with the body. For many people paying additional sum of 490 $ for a lens which only slightly improves the performance of the kit lens might be going over the top. Others, though, won’t hesitate a moment and will invest in the much more universal Pentax 17-70 mm.

The comparison between the Pentax and the Sigma shows a slight advantage of the former. There’s just one snag – you can buy a Sigma for the amount of about 370 $ but for a Pentax you must scrape up around 120 $ more. A bit better quality, minimally better optics and a SDM motor are Pentax’s strong points. The fastness, the price and well done near-makro are Sigma’s strong points. A choice really difficult to make but who is to say the photographic equipment completing is easy?

Please Support Us

If you enjoy our reviews and articles, and you want us to continue our work please, support our website by donating through PayPal. The funds are going to be used for paying our editorial team, renting servers, and equipping our testing studio; only that way we will be able to continue providing you interesting content for free.

- - - - - - - - - - - - - - - - - advertisement - - - - - - - - - - - - - - - - -

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Sample shots:


Camera: Pentax K20D Parameters: 17 mm, f/4.0, exp. 1/2000 sec., ISO 200 File: JPG, 4672x3104 pix, 10.1 MB	Camera: Pentax K20D Parameters: 17 mm, f/5.6, exp. 1/1250 sec., ISO 200 File: JPG, 4672x3104 pix, 10.1 MB	Camera: Pentax K20D Parameters: 30 mm, f/8.0, exp. 1/800 sec., ISO 200 File: JPG, 4672x3104 pix, 9.6 MB

Camera: Pentax K20D Parameters: 48 mm, f/5.6, exp. 1/1600 sec., ISO 200 File: JPG, 4672x3104 pix, 9.1 MB	Camera: Pentax K20D Parameters: 70 mm, f/5.6, exp. 1/1600 sec., ISO 200 File: JPG, 4672x3104 pix, 8.8 MB	Camera: Pentax K20D Parameters: 70 mm, f/8.0, exp. 1/800 sec., ISO 200 File: JPG, 4672x3104 pix, 9.1 MB

Camera: Pentax K20D Parameters: 23 mm, f/6.3, exp. 1/800 sec., ISO 200 File: JPG, 4672x3104 pix, 10.1 MB	Camera: Pentax K20D Parameters: 48 mm, f/8.0, exp. 1/125 sec., ISO 200 File: JPG, 4672x3104 pix, 11.0 MB	Camera: Pentax K20D Parameters: 23 mm, f/5.6, exp. 1/400 sec., ISO 100 File: JPG, 4672x3104 pix, 10.1 MB

Camera: Pentax K20D Parameters: 70 mm, f/11.0, exp. 1/320 sec., ISO 400 File: JPG, 4672x3104 pix, 10.0 MB	Camera: Pentax K20D Parameters: 48 mm, f/4.0, exp. 1/640 sec., ISO 200 File: JPG, 4672x3104 pix, 8.8 MB	Camera: Pentax K20D Parameters: 48 mm, f/4.0, exp. 1/125 sec., ISO 400 File: JPG, 4672x3104 pix, 9.4 MB

Camera: Pentax K20D Parameters: 70 mm, f/4.0, exp. 1/80 sec., ISO 200 File: JPG, 4672x3104 pix, 9.3 MB	Camera: Pentax K20D Parameters: 33 mm, f/4.0, exp. 1/100 sec., ISO 200 File: JPG, 4672x3104 pix, 9.3 MB	Camera: Pentax K20D Parameters: 70 mm, f/5.0, exp. 1/100 sec., ISO 200 File: JPG, 4672x3104 pix, 8.6 MB

Camera: Pentax K20D Parameters: 53 mm, f/4.0, exp. 1/160 sec., ISO 200 File: JPG, 4672x3104 pix, 8.5 MB	Camera: Pentax K20D Parameters: 39 mm, f/4.0, exp. 1/250 sec., ISO 200 File: JPG, 4672x3104 pix, 10.2 MB	Camera: Pentax K20D Parameters: 17 mm, f/4.0, exp. 1/200 sec., ISO 200 File: JPG, 4672x3104 pix, 11.4 MB