Totally torn...

...and I'm wondering if I should just wait to make a decision. Here's my current situation. I used a big chunk of my "startup" money (money to buy equipment at my university job) on a 70-200 2.8L IS, which should be here soon. I have a T1i, the 18-55 kit lens (which I find a bit soft, flimsy, and imprecise in low light), the 430EX II, and the EF 50/1.8.

Since just before x-mas, I've *had* the Tamron 28-75. I generally liked the IQ on that; but the build quality left a lot to be desired. It just felt "loose" and would wiggle a bit. Plus, I was missing the wide end a little and found myself shooting at the extremes of the lens -- 28mm and 70-75mm. So I sent it back to Amazon. As I mentioned above, I'm not really happy with the kit lens (aside for being a backup) and I'm looking for something at the wide (though not ultra-wide) end ... mostly for candids in close quarters (e.g., at the bar) and some general walk-about type stuff (architectural shots, street scenes, etc.). I know there are a million threads on this, but I still couldn't figure it out based on my circumstances; so here are my choices:

Tamron 17-50/2.8
Canon 17-40/4L

I know, I know. Just bear with me here....

I'm not really worried about the 40-50 range. If I want to shoot at 50, I'll put on my Nifty or I'll just move my body. A big part of me knows that I should probably choose the Tamron given that I was generally happy with the IQ its slightly bigger brother offered; but I'm worried about its build ... and I can't stop going back to the BEAUTIFUL pictures in the 17-40 images thread. On the other hand, I recognize that a lot of those pictures were shot on FF cameras; even those shot on crops, though, are just stunning. Plus, the accurate, quick, and quiet AF of the 17-40 would be mighty nice.

Given that I've been taking my flash with me just about everywhere, am I going to miss the open end of the Tammy if I were to go with the Canon? Am I going to find myself SOL in museums or at weddings where flash is less of an option? Let me try to break down what I'm attempting to weigh:

Tamron Pros:

1. wider aperture
   
2. wider focal range (by 10mm)
   
3. longer warranty
   
4. cheaper
   

1. only okay buld quality
   
2. loud AF that can hunt
   

1. better color and contrast
   
2. fast, quiet, and accurate AF
   
3. great build quality
   
4. FF compatibility (many years down the road)
   

1. expensive
   
2. only f/4
   

For what you are going to be shooting IMHO that Tamron will be just fine in terms of AF speed and the faster aperture will come in handy again and again. The only reason IMO to get the Canon in this situation would be if you need to track fast things... which from what you described you dont need to.

Build quality on the Tamron however will leave something to be desired, although I hear the new VC version of the lens has much better build quality and faster and less noisy AF to go along with the VC.

I had the Tamron 17-50 VC F2.8 for ten days and didn't like it at all. Wife gave me the Tamron for a Christmas gift but I returned it yesterday. Ran some test between the 17-50 and the 17-85 Canon and the Canon won hands down. The Canon was much sharper than the Tamron at the same F-stops by quite a bit. Shooting the Tamron at f2.8, the pictures were so noisy, I wouldn't ever want to print or post any of those shots. I'm upgrading the returned Tamron for a Canon 24-105 F4L. To me paying the extra $350.00 in well worth the difference.

I haven't used the 17-50 yet (I would if it would mount on a FF) but I've heard and seen good things about it.

If you're looking to cover the low range, keep in mind that the difference between 17mm (27.2mm on a 1.6x) and 28mm (44.8mm) is huge.

In terms of build quality, the L lens should leave you well satisfied.

Edit: Also, (I'm sounding biased now, I know) if you're shooting with a flash, you'll generally stop down to f/3.5 or f/4 anyways, so if that's the case, you're comparing two f/4 lenses here. Unless you shoot low light, the f/4 shouldn't bother you much.

Oh and I forgot to mention if you are going to be going FF anytime soon then well you might wanna plan ahead and get the Canon in that case.

If you are in a budget, like me, the 17-50 will satisfy your needs. I'm sure you have seen the great quality this little lens can produce. Reason I'm getting one. Now, the Canon L lens has a better build quality and stunning pictures. Only reason I'm not getting it because it's to much dinero.

If you are looking for better build quality and basically great bang for your buck, I would get the Canon 17-40 4L and use the nifty fifty for low light situation, that if it's not hunting all the time.

Though if your saving money and want to learn the feel of the camera, how to take great quality shots, and basically learn before you plunge your money with a better lens, I would recommend the Tamron 17-50. That's basically what I'm doing. I'm getting the tammy to understand what my camera has to offer and what picture it can produce, once I get the handle of it. Then I will upgrade to an L lens.

Bottom line it's your choice.
just my 0.02

Just to add to your debate (which you've laid out very clearly), how 'bout the Tammy 17-50/2.8 VC... at about the same price as the 17-40, you get the f/2.8 extra stop, plus up to 4 more stops from the stabilization (according to marketing )... I haven't used the Tamron 17-50, but I've been very happy with the other Tamron SP lenses I've had (90mm macro, 70-200/2.8 (x2, I've had it for two systems), and the 400mm f/4 MF adaptall-2...) I also have the 17-40 L, and it's a beautiful lens. With choices like these, you can't go wrong .

As I see it, your debate is how often you'll need f/2.8 and be kicking yourself without it, vs. how much you value the aesthetics of the equipment your working with (L, L, L ). Tough call!

Dokk wrote in post #9341608
I'm looking for something at the wide (though not ultra-wide) end ... mostly for candids in close quarters (e.g., at the bar) and some general walk-about type stuff (architectural shots, street scenes, etc.).

Remember wide angle starts at 35mm downwards. The 17-40 is technically a Ultra-wide angle, but since you're mounting it on a APS-C 1.6x sensor, you really have a 27.2mm-64mm. The difference between the two is actually 16mm, rather than 10.

With regards to museums, I've found that the lighting in museums (paintings and display cases) is usually quite good. If you have a steady hand, you can take good shots with the 17-40. The challenge are the statues and such that may not have a beam of light on them.

I would choose 1740L for its speed AF in low light, better than 1750 Tammy.
I ever had 1750 Tamron 2 years ago and found that it's difficult to search & lock the focus in low light condition.
Second reason, the IQ quality is much better on Canon.
Third reason, Tammy's motor is (quite) louder than 1740L and it's annoying for me.

Well, at least this reply is based on my experience.

The majority of you are bad influences...

...but y'all already know that, I'm sure.

Thanks for the thoughts, experiences, and advice. Please keep it coming!

I can only say of good things about that tammy:
it's a wonderful lens.

I guess what some of us are asking you by posting what we think indirectly although directly in this post, lol, how much low light stuff are you going to be doing? how much "Action" photography will you be doing? are you going to upgrade to FF anytime soon?

How much do you really love that "L" ?

Its ultimately what you need in a lens is what most people will decide from and tell you what they think you should get... not that you haven't already described what you will be using the lens for... its just more particular details will help even more.

Seeing that the OP bought a 70-200 I think after using the red ring he'll get spoiled.

For a cropper I think the Canon 17-55 will be the expensive solution that is not the 2 lenses mentioned. Even though its not an L lens the USM is much appreciated.

I would say the IQ of the 17-40L on a cropper is wonderful. Colours and contrast from this lens is wicked even straight out of the camera. USM is superior to a buzzy 3rd party lens. I will admit HSM of a Sigma is very good though. I regretted not buying my 17-40L instead of my Sigma 18-50EX Macro. After buying a full frame I immediately bought my 17-40L.

If you want shallower dof use primes.

I replaced my kitlens with a 17-40, am very pleased with it. I'm getting spoilt and getting annoyed by the f/4 though, so like you a 16-35 would be ideal but for now Ill have to do with 4 until money falls out of the sky
I guess the question is are you planning to switch to FF? I am, thats why I got the 17-40.
I'm pretty sure its my most used lens. Not too heavy (compared with the brick or tele L), still pretty wide on crop, 40-50 gap doesn't bother me at all, soooo sharp. But I will definitely say it isn't perfect, particularly in low light its kinda useless (without flash).