Low light camera lens?

So I'm going to a few concerts and I was wonders what lens is good in low light? I've got the Nikon D3100 yesterday I brought the 55-200 VR lens.

As well as the low light lens I need one with a decent zoom because I'm not sitting right at the front.

I don't want to spend stupid money

It's a compromise
Prime luminous lenses, about f1.4 won't allow you getting close to stage; the zoom you own has not so wide aperture but you can set ISO and get better shots

The closer the lens aperture can get to 1.0 the more light it can collect (and the more expensive it gets)
It is almost never true that an adjustable zoom lens can have a large aperture and non-adjustable telephoto that have 1.4 or 1.2 lenses being available, cost money.
But the good news is that the actual light for taking pictures of the stage is not a low light level although further away. If you want to take pictures of the audience with light from the stage, that is low light level but usually close.
And as one of the answers says, modern digital cameras have ISO rating far beyond what film users had to live with.

For good results in low light you need a lens with large max aperture, thus f1.8 or f2.8. If you also need quite a degree of tele (zoom) then you need to spend silly money on something such as a 70mm to 200mm at f2.8. There are no two ways about it - that is the ideal set-up, and that is why professionals spend silly money to get suitable equipment.

But try raising the ISO if you can accept a certain amount of graininess, and use the 55 to 200 that you have.

If you are talking about a concert then be aware that most venues don't allow 'professional' cameras, and thus anything bigger than a compact will be forbidden. The goons they call 'security staff' do not know the difference between an entry-level DSLR and one that might generally be used by professionals. Maybe contact the venue rather than take your D3100 with you and have it refused entry.

The first compromise for a lens to get the zoom function is aperture (there are many others), in low light you need a wide (low f number) lens to gather as much light as possible to get reasonably fast shutter speeds. The alternative is to up the ISO, not as bad in terms of noise as it used to be, but still a compromise. It's better to get a noisy shot, which can be reduced in post processing, than a blurred shot which can't.

My lens of choice for gigs is the Sigma 70 - 200mm f2.8. A wide aperture lens with 'reach', but it's a big heavy lens which will cost you more than your camera. It's also 'Pro' gear which often is not allowed into concerts.

I get a lot of success with a Pentax Q and a 50mm f1.4 lens, because of the small sensor and large crop factor I get the equivalent of a 275mm f1.4 lens! The lens cost £60, the Q-K adapter £25 off eBay. Currently youy can buy the Q body for £69. The complete kit is tiny, but I get saleable results.

Chris

Security don't take the Pentax Q seriously so I can get in anywhere with it.