I know this has been discussed more often the one can count, but I have never addressed this subject and want to share some of my impressions and recommendations. But finding a good zoom lens on a budget can be a nerve racking experience.
Fixed focal length lenses are no longer the be all and end all in lens optics heaven. I have used several zoom lenses that compete quit readily with some of the fixed lenses I have used.
In fact I would go as far as saying that even some of the standard zooms can do the trick if stopped down a stop or two. Some even rate excellent wide open. The only draw back is that when wishing to really blow out the background, you will either have to shoot longer i.e. from 100 to 200 mm or use a fast fixed lens like a 50 1.8 or faster.
Here are a few lenses that I would feel comfortable using for professional applications. They are all budget priced lenses and accessible to most of us.
I would love to hear from those of you using zooms and your impressions
Canon EF-S 55-250mm f/4-5.6 IS II
Canon EF-S 18-55mm f/3.5-5.6 IS (Very sharp stopped down one stop)
Nikon AF-S DX NIKKOR 18-55mm f/3.5-5.6G VR ( a great lens for the money)
Nikon AF-S DX NIKKOR 18-105mm f/3.5-5.6G ED VR
Pentax-smc-DA-18-55mm-f3.5-5.6-AL-II-IF (An incredible lens for the money)
Pentax SMC P-DA 50-200MM F4-5.6 ED
Sony 18-55mm f/3.5-5.6 DT SAM SAL-1855 (very nice lens and fast auto focus)
Sony 55-200mm f/4-5.6 SAM DT
Tamron AF55-200mm F/4-5.6 Di II ( a bit slow to focus, but good optics if stopped down one stop)
I will add the Tamron 28-75 f2.8 although quite a bit more expensive. But compared to comparable lenses, it is a steal!
Sigma 18-50mm F2.8-4.5 DC OS HSM (a bit more pricy)
Sigma 55-200mm f/4-5.6 DC (excellent for a very inexpensive lens) Stop down at longer focal lengths around one stop)
Sigma AF 18-50mm f/3.5-5.6 DC
Tokina AT-X 16.5-135 DX 16.5-135 mm f/3.5-5.6
Well there you have it for now. Looking forward to your suggestions on a budget.