Sigma 17-70mm or Tamron 17-50mm??

Hi there,

I've been looking around on this forum for both this lenses..but I still have my doubts.

I'm looking for a "standard zoomlens" (little bit wide angle <> normal zoom) for my Canon 30D (crop)camera. I'd like to use the lens for daily stuff, around the house, quick pictures, as well as studio photography once in a while.
I know that when I am outside my canon 10-22 is perfect for landscapes or other funky effects..and I am planning to buy a 70-300 as well.
So, logically, a Sigma 17-70 (which I have worked with a couple of times) should be perfect to fill up the gaps. I don't want the Canon 17-85, due to it's distortions and softness, neither the 17-55...that one one simply too expensive and if I'd save money I could better go with the 24-70/105L though

But after looking this 2 threads...

Sigma 17-70mm
https://photography-on-the.net/forum/showthre​ad.php?t=186589
Tamron 17-50mm
https://photography-on-the.net/forum/showthre​ad.php?t=209580

So what do you guys think? which one do your prefer?
I have the idea that the Tamron has a much greater contrast and "better" colors over the Sigma.. I know it's a F2.8 over the whole range..but the Sigma has F4.5 on the high end, and that doesn't really bother me either (I also use my speedlight and I even work in the studio ofcourse)
One plus of the Sigma is it's 'macro' function and the build quality...

So, are there any significantly differences, or does it only depent on the photograpgher and the light/circumstances at the moment the pictures (for example those from the threads) were shot?

And my second question:
What's the difference between 50mm and 70mm...simply one step foreward? and would I miss the 20mm zoom part in the studio? (I like the 50mmF1.8 and I even have the possibily to use the 28-135...)

Due to the 30D, which is a cropcamera, I don't want any 28--xxxmm lenses as a normal zoomlens, 'cause I like the wide angle so much! 24mm should be the maximum
When I used an exif viewer on some old pictures, shot by the kitlens, I used both my 18mm and 55mm alot in my "walkaround"

Thanks!

I think the Tamron gets more rave reviews. I wouldn't worry about any gap form 50-70.

prinspaul wrote in post #4648997
the Sigma has F4.5 on the high end, and that doesn't really bother me either (I also use my speedlight and I even work in the studio ofcourse)

I own the Tamron and it is a very nice lens .. the IQ is on par with the Canon 17-55 2.8, which is quite a compliment.

Do not dismiss the maximum aperture difference of 2.8 vs 4.5 so easily .. a flash cannot always compensate for the loss of a stop and a half of light. And if you're doing studio work the constant aperture will be a time saver with caculations & adjustments to your strobes.

I've never used the Sigma so cannot comment directly on it .. there have been numerous (as in dozens) of threads recently of the Tamron 17-50 versus Canon 17-55 versus Sigma 17-70 variety so it should be easy to find lots of comparisions.

i'm contemplating the two lenses myself. im leaning towards the tamron for the f2.8

yea..thanks.

I defintly find the f2.8 a big plus! it's a pity the build quality of the Tamrom seems to be more plastic and it makes more noise..

@mmahoney: I don't dimiss the f2.8 that easily indeed, but I mean that when I am i the studio, I mainly work with F9-11 or somehwere in that range... and I think both the lenses will performing excellent there.

Does anybody know if the AF of Tamron is comparible to those of Sigma?

And as a general question..
Which lenses would you advise? Maybe I am looking for the wrong ones. there isn't alot of choice in the 17/18mm range...
I should I better save money for a 17-55? ...it's almost 3 times more expensive:s

prinspaul wrote in post #4649701
yea..thanks.

I defintly find the f2.8 a big plus! it's a pity the build quality of the Tamrom seems to be more plastic and it makes more noise..

I think the build quality of my Tamron is amazingly good, especially compared to the kit lens *puke*

I just got the 17-50 and the 2.8 is great. I like it so far. I was also debating between the 17-70 and 17-50.

I had the Sigma 17-70 and sold it for the Tmron 17-50. Both are great lenses, especially for the price. I have found the AF on the Tamron to be much more accurate than Sigma, especially with a high contrast background. The AF is louder and higher pitched, but basically the same speed. The constant 2.8 of the Tamron also allows the center AF point of the 30D to become a cross-type (should be more sensitive). Sharpness-wise, both are very sharp, although I think my Tamron is sharper at the wide end than my Sigma was. At first, I missed the extra length of the Sigma, but being able to blur the background with the 2.8 is really nice. As I said earlier, both are nice lenses. I am happy with the decision I made, but I think you would probably be happy with either lens. Just be aware of the difference the smaller aperature at the Sigma's long end will make.

Personally I would go with the Tamron as well. Speed of focus and f/2.8 compared to the Sigma make it worth while.

Tough call, but I give the nod to the Tammy.

ok...that's clear!!

indeed, I think the difference between 17-24/28 is much greater than the 50-70mm gap

@Pgiancola/350dinhand: I see you (both) have the 50f1.8 as well. tmonatr mentionced 'the AF is louder and higher picthed' ...to be honest, I find the nifty50 already very loud! haha, can I compare the tamron with this lens?? Not that the 'loudness' should be a big deal, but it's just curiousity.

I think I will go with the Tammy.. although I can't stop thinking about the 17-55 IS..maybe I am better off by waiting a few months to buy that one (some people talk about its hidden 'L' features, and lenses are an investment anyway)
On the other hand; the 17-50 seems to be a very good lens for its money..maybe I should try it somewhere!

doubts, doubts.

I'd go with the Tamron myself. If you want more versatility, lower price, and more range in exchange for constant aperture and better optics, then the Sigma.

I went for the Sigma 17-70 and a Tamron 28-75/2.8 for the best of both worlds

I used to have the Tamron 17-50 as well and I'd say the 2 lenses (Tamron 17-50 and Sigma 17-70) are pretty much the same at f/5.6 or more. At wider apertures the Tamron is sharper. It may be that the Sigma images have a tough more 'pop' for landscapes, but I can't be 100% sure about that (it's certainly no worse). Build quality is also a tie, although I prefer the matt finish of the Sigma. In my experience the Sigma is better at focussing - the Tamron would occasionally be out in lower light or lower contrast situations.

I had to exchange my first copy of the Sigma (for back focus) and get the Tamron repaired (for a de-centered element), so I'd say quality control is also a tie! Actually, to be fair, I hear of more problems with the Sigma than the Tamron - if you get one make sure you can return it easily

The Tamron motor is definitely higher pitched than the nifty....more electro-mechanical sounding. The nifty sounds like plastic grating and buzzing "szhoot szhoot clack szhoot szhoot szhoot" oh sorry, there is not enough ambient light and my nifty has failed to lock focus "szhoot szhoot szhoot".

i choose Tamron, most of the reviews out there said Tamron is better overall...