You'll be very pleased with the 17-55 IS. I had a 24-70 and sold it to get the wider 17-55. I found the IS to come in handy quite frequently. There was no noticeable difference in sharpness but I do find that the 17-55 needs a slight boost in contrast to get what the 24-70 had.
construction... EF-S 10-22mm F/3.5-4.5 is your best bet, or the Tilt/Shift 17mm
flowers... EF 100mm F/2.8 or the EF 100mm F/2.8L IS
birds... your best choice is the EF 800mm F/5.6L IS, the EF 600mm F/4L IS, or the EF 500mm F/4L IS.
those three requirements are too diverse to have a single lens for (especially the birds)
I used the 17-40 on my crop 40D as my walk around lens and hardly used the 24-70 but on my FF 5D Mk2 I use the 24-70 all the time and only put the 17-40 on on rare landscape occasions
Niall
Another vote for the 17-55/2.8 IS. I traded a 24-105/4 IS for it 2 years ago and am very happy I did. In the past year I sold a 35/1.4 L and Sigma 50/1.4 as they became redundant by it.
I am still horse trading lenses, sometimes for the better, sometimes not. but one thing is clear, I'm not tempted to trade this lens for anything. maybe there's something better (for my needs, today) but I seriously doubt it.
Well after some thought, I went with the 7d (it has some good features I like),and the 17-40L spent more on the body,so this was the only lens i could buy. The one big factor was the lens and the camera are weather proof,and since i will be taking picture at construction sites I thought this was the best way to go.Thanks for all your help.
Re-reading your original post I'll expect you'll have no problems outdoors, but indoors with the children might pose a challenge at f/4 even with the new 7D, but at least you have a pop up flash to help you out a little
while I have the 24-70L, my first lens was a 17-40L. On my 40D 1.6x crop, I find that I use this in all of my portrait sessions besides my f/1.4 50mm. For the price and the amount I use it, I see that my 17-40 is definitely the better value than my 24-70L.
Jeff Fletcher wrote:
Well after some thought, I went with the 7d (it has some good features I like),and the 17-40L spent more on the body,so this was the only lens i could buy. The one big factor was the lens and the camera are weather proof,and since i will be taking picture at construction sites I thought this was the best way to go.Thanks for all your help.
The 7D does not have a lens mount gasket...IOW your 50D was/is just as effective. I too think you will have a problem shooting indoors
Jeff Fletcher wrote:
Well after some thought, I went with the 7d (it has some good features I like),and the 17-40L spent more on the body,so this was the only lens i could buy. The one big factor was the lens and the camera are weather proof,and since i will be taking picture at construction sites I thought this was the best way to go.Thanks for all your help.
The 17-40L was the lens most often mounted on my 40D. I just got a 7D and I expect to keep using the same lens. I've never found the f/4 a problem. Indoors, I usually bounce flash off the ceiling. With the 7D, I expect the better ISO performance to increase the opportunities for using natural light.
I've often considered getting the 17-55 mainly to get IS and the extra reach. f/2.8 is not important to me in a wide-ish angle lens. So far, I haven't been able to convince myself to make the switch. I also have a 28-75/f2.8, 50/1.8 and 85/1.8 to cover most situations.
