Nikon D3100 Zoom Lenses that have a f/2.8 or faster aperture

"This is my main general purpose lens and I'm well pleased with it's sharpness, versatility, useful focal range, weight and feel both on the D700 and D300." bhphotovideo.com

	Aperture	f/2.8			Length	81 mm
	Image stabilization	None			Max focal length	85 mm
	Focus motor	None			Weight	0.5 kg
	Fixed aperture	No			Zoom range	3.5x

"The lens is fast and sharp. A real joy to use." bhphotovideo.com

	Aperture	f/2.8			Length	132 mm
	Image stabilization	None			Max focal length	70 mm
	Focus motor	Nikon AF-S			Weight	0.9 kg
	Fixed aperture	Yes			Zoom range	2.9x

"The colors this lens can capture are outstanding!" bhphotovideo.com

	Aperture	f/2.8			Length	132 mm
	Image stabilization	None			Max focal length	24 mm
	Focus motor	Nikon AF-S			Weight	1 kg
	Fixed aperture	Yes			Zoom range	1.7x

"The build quality is very good, focus and zoom ring are nicely damped and operate smoothly. You do not experiance any wobbling and the lens features the well known EX finish." bhphotovideo.com

	Aperture	f/2.8			Length	94 mm
	Image stabilization	None			Max focal length	70 mm
	Focus motor	Sigma HSM			Weight	0.8 kg
	Fixed aperture	Yes			Zoom range	2.9x

"I've owned this lens for two weeks and couldn't be happier. I've shot images of dogs running full speed and the focus keeps up with them. I've also shot some humans at 150mm @1/30th sec. and they are as sharp as could be. I am 100% happy with this lens." bhphotovideo.com

More advanced image stabilization Nikon VR II

Great telephoto lens 200 mm

	Aperture	f/2.8			Length	206 mm
	Image stabilization	Nikon VR II			Max focal length	200 mm
	Focus motor	Nikon AF-S			Weight	1.5 kg
	Fixed aperture	Yes			Zoom range	2.9x