Sigma 17-70 F2.8-4.5 - User Review -

[Cadwell]

Mmm... or how about buying the 24-105mm if you don't want the edge softeness or the CA? Perhaps the weather sealing would be nice or the much faster and quieter autofocus? Maybe full time manual focus?

I've actually just bought a Sigma 17-70mm to put on my old 10D and use it as a camera to keep in the car. It isn't a bad lens. I was quite impressed by the build given the price. Certainly a Canon lens at this price point would be much flimsier. Does it have the same finish as a Sigma EX? Superficially it looks similar but it doen't bear comparison to that on my two genuine Sigma EX lenses (120-300mm f/2.8 and 500mm f/4.5). The optics are OK... pretty good really for the money but L busting when examined closely? No. Mind you I didn't expect them to be. All in all I am quite happy with the Sigma;it will do what I want and is ideal for the application I have in mind.

The bad news? It took me three copies to get one that didn't have serious back focus issues. Thankfully I have a very understanding supplier (that might be down to the amount of money I've spent with them over the years ) but even so, having to test and repackage 2 lenses before I got one that worked right was a pain. I also noticed that all three copies of the lens show reluctance to AF if you start off with them really out of focus when pointing at a low contrast subject. Give them a little helping nudge by manualy focusing them somewhere near and they are fine but without full time manual focus override this becomes a little fiddly.

You gets what you pay for and if you can find a good copy, this lens is a bit of a bargain.

[JMHPhotography]

Originally Posted by Nick_C

But that would be completely unfair, the Canon has IS, the Sigma doesnt, but on the Sigmas side it has F2.8!

We all know the benefits of IS, & that is one of the key selling points of the 24-105, but this wasnt supposed to be a Sigma vs Canon debate, purely just to demostrate the fine optics of the 17-70, nothing more.

Nick

I think it is fair. If you're going to post a test between two lenses, you should test them both under the same conditions, and vary the conditions for both equally. Last time I checked, they didn't do school plays, or dance recitals, or school award ceremonies outdoors under partly cloudy skies. Some noob sees this thread, and rushes out to by the Sigma 17-70 thinking it's as good or better will be very disspointed when they see thier pictures from it under those conditions.

NOTE: I actually OWN and LIKE my Sigma 17-70mm but I also knew what I was buying and how I'd be using it befrore doing so.

[JMHPhotography]

Originally Posted by canon_fire

hmmm ... so to those who have had both at the same time and do serious shooting .. I have to ask, Would my time and all be worth it upping to the 24-105 L over the sig 17-70??

I don't have the 24-105L but I have the 24-70L and the Sigma 17-70 which I think is a more realistic comparison since the ranges are much closer and the 24-70L doesn't have the unfair advantage of the IS, and to be perfectly honest... when I'm doing a paid wedding, or paid job. I will 10 times out of 10 reach for the 24-70L. Image quality aside... I get faster and more responsive AF, silent AF, F/2.8 throughout the range...(the 17-70 is only f/2.8 at the 17-20ish setting, btw), and on top of this... the 24-70L just plain makes better images.

So why do I own the 17-70?? When I go out and just want to grab some happy snaps... Carrying my bag isn't the most convenient thing in the world. My 20D and 17-70 make a fantastic setup for quick snaps of everyday life.

20D with Sigma 17-70... f/3.5 at 33mm and 1/160 and ISO 800 with no flash

[Nick_C]

Originally Posted by Cadwell

Mmm... or how about buying the 24-105mm if you don't want the edge softeness or the CA? Perhaps the weather sealing would be nice or the much faster and quieter autofocus? Maybe full time manual focus?

I've actually just bought a Sigma 17-70mm to put on my old 10D and use it as a camera to keep in the car. It isn't a bad lens. I was quite impressed by the build given the price. Certainly a Canon lens at this price point would be much flimsier. Does it have the same finish as a Sigma EX? Superficially it looks similar but it doen't bear comparison to that on my two genuine Sigma EX lenses (120-300mm f/2.8 and 500mm f/4.5). The optics are OK... pretty good really for the money but L busting when examined closely? No. Mind you I didn't expect them to be. All in all I am quite happy with the Sigma;it will do what I want and is ideal for the application I have in mind.

The bad news? It took me three copies to get one that didn't have serious back focus issues. Thankfully I have a very understanding supplier (that might be down to the amount of money I've spent with them over the years ) but even so, having to test and repackage 2 lenses before I got one that worked right was a pain. I also noticed that all three copies of the lens show reluctance to AF if you start off with them really out of focus when pointing at a low contrast subject. Give them a little helping nudge by manualy focusing them somewhere near and they are fine but without full time manual focus override this becomes a little fiddly.

You gets what you pay for and if you can find a good copy, this lens is a bit of a bargain.

Well I have found that the 24-105L has edge softness just the same as the 17-70, buying the Canon wont get rid of that issue, its probably much better when mounted on a 1.6x body but its not a very nice focal range then.

As for the other features like full time focussing & IS, well all I was comparing was IQ, features aside yes the Canon is more packed with goodies, but the price is MUCH more so I would expect more, however I still believe the 17-70 certainly CAN match an L for optics, the L may have the edge but its not as much of a difference as some L fanatics make out!

Nick

[Nick_C]

Originally Posted by forkball

I don't have the 24-105L but I have the 24-70L and the Sigma 17-70 which I think is a more realistic comparison since the ranges are much closer and the 24-70L doesn't have the unfair advantage of the IS, and to be perfectly honest... when I'm doing a paid wedding, or paid job. I will 10 times out of 10 reach for the 24-70L. Image quality aside... I get faster and more responsive AF, silent AF, F/2.8 throughout the range...(the 17-70 is only f/2.8 at the 17-20ish setting, btw), and on top of this... the 24-70L just plain makes better images.

So why do I own the 17-70?? When I go out and just want to grab some happy snaps... Carrying my bag isn't the most convenient thing in the world. My 20D and 17-70 make a fantastic setup for quick snaps of everyday life.

20D with Sigma 17-70... f/3.5 at 33mm and 1/160 and ISO 800 with no flash

I reason why I compared against the 24-105 is mainly because its what I have, but also because the 17-70 is really a 27-112mm lens, so its near enough to the 24-105.

As far as the 24-105 having un unfair advantage in the form of IS, all the tests were done with IS turned off so that it didnt have any gain over the 17-70.

Of course the L lenses will always have the edge, but the difference isnt always as much as you would expect it to be.

Nick

[Cadwell]

Originally Posted by Nick_C

the L may have the edge but its not as much of a difference as some L fanatics make out!

I am hardly an L fanatic, in fact I'm quite famous around this forum for not being one!

[Nick_C]

Originally Posted by Cadwell

I am hardly an L fanatic, in fact I'm quite famous around this forum for not being one!

Sorry no I wasnt directing that at you, I was referring to some others I have seen on here.

Nick

[Bosman]

What are the max apertures by focal length?

[Bosman]

Found an awesome deal on this lens

http://www.bestpricecameras.com/prod...?prodid=481956

[canon_fire]

hmmm .... I better buy 3

[Nick_C]

Originally Posted by Bosman

What are the max apertures by focal length?

I have seen this on the forum someplace, I will see if I can find it for you unless somebody else has the figures.

Nick

[LightRules]

Originally Posted by Bosman

What are the max apertures by focal length?

17-20mm 2.8
21-24mm 3.2
25-34mm 3.5
35-54mm 4.0
55-70mm 4.5

[taken from my 1785 and 1770 review http://www.pbase.com/lightrules/17701785 ]

[LightRules]

Originally Posted by Bosman

Found an awesome deal on this lens

http://www.bestpricecameras.com/prod...?prodid=481956

Originally Posted by canon_fire

hmmm .... I better buy 3

Hey, at least you get free shipping

In all seriousness, stay away from www.bestpricescameras.con

[Nick_C]

Originally Posted by LightRules

17-20mm 2.8
21-24mm 3.2
25-34mm 3.5
35-54mm 4.0
55-70mm 4.5

[taken from my 1785 and 1770 review http://www.pbase.com/lightrules/17701785 ]

I thought I saw that somewhere

Nick

[Bosman]

Thanks!

And also thanks to Nick for another great review!

Sometimes I think the Sigma 17-70 would make a better walk around than my Tamron28-75, but I do love the f2.8. But your review has me pondering this again.

Cheers

Joe