The 17-55 f2.8 would probably be the best fit. You could also look at the 24-70 f2.8. Those would be your options for new lenses, but you also might be able to find used a 28-70 f2.8 or 35-70 f2.8, which both have good reputations.
Do you need an f2.8 lens? There are some pretty good options that are smaller, lighter, and less expensive if you don't, and you could pair a less expensive zoom with a 35 f1.8 and/or 50 f1.8 when you need the wider aperture. For example, a 16-85 along with 35 f1.8 and 50 f1.8 would cost less than just a 17-55.
Welcome to Nikonians! If you want a Nikkor constant aperture f/2.8 zoom, the 17-55mm would be my first choice on a DX body. I have found the 17-55mm to be a much more useful range than the 24-70mm, 28-70mm, or 35-70mm on a DX body. One thing to keep in mind is the 17-55mm is significantly heavier than your D50. Remember that "Fast Glass" is addictive. Good Luck and Enjoy your Nikons!
Thanks guys for your help. Yes I think the f/2.8 is a bit too much for me. What I really need is a good lens for poorly lit places such as a church. I get very granulated pics with my Tamron lens 28-85mm because my aperture' maximum at 28mm is 3.5. I want to get the pics right in this church but have not managed yet. I also increased the ISO to 1600 and the black keeping coming granulated and there is no sharpness. I was thinking of buying a good lens for this but maybe the 35mm f/1.8 will do the job or even the 50 mm f/1.8, though I still cannot understand how people get decent pics with Tamron lens mounted on a Nikon like mine.
Yep. This is a common misunderstanding. Those fast and expensive f/2.8 zooms are... a half a stop faster than f/3.5. That's the difference between 1/45th and 1/60th in shutter speed! It's good to have that additional speed, but it sure won't change the game.
An f/1.8 might - that's about two stops faster, or 4x the shutter speed. That moves your shutter speed from 1/45th to 1/180th, which is quite a difference.
> I also increased the ISO to 1600 and the black keeping coming granulated and there is no sharpness.
Is the sharpness in the area of focus, or not? If not, no big deal, it's not in focus anyway. If so, the problem isn't the lens - it's your ability to hold the camera still during the long shutter speed. You need either a faster lens, a flash, or a tripod.
> cannot understand how people get decent pics with Tamron lens mounted on a Nikon like mine.
It's nothing to do with Tamron, nor Nikon. It's all about technique and what it can do (and, sometimes, can't). The "granulated" look in the blacks is due to underexposure, and that can be cured in camera. But you may need a tripod for that, and even that only works if the subject isn't moving (much).
_____ Brian... a bicoastal Nikonian and Team Member
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