Sharper images with less noise
Do you avoid high ISO settings, because your pictures get too much noise? With the right technique, you can minimize the noise and highlight details of the picture.
Get to know your camera
If you check your most noisy images, you'll soon discover that the noise is most prominent in the shadows and dark areas. This is because the camera's sensor must work harder to increase the light sensitivity of these faint parts of the image, resulting in noise. If you overexpose the image slightly and let in more light, the electronics will need to work less with less noise as a result. I allways overexpose pictures with low light and high ISO between +2 / 3 - +1 EV. The picture will be slightly brighter than normal, but I will compensate this by underexposing a bit in Lightroom to get back the exposure to normal. By testing in poor lighting, you can find out how your camera reacts. The only thing you should be aware of, is to not blow out the highlights. This technique is called "Expose to the right", which comes from that you push the information in the histogram to the right.
Let the program to the hard work
I use Lightroom for almost all editing in my street photos. Noise reduction and sharpening works well on most images, and with a little fine tuning can reduce most noise. In really heavily noisy images LightRoom will not be sufficient. For thos images I use more advanced programs such as DxO Optics Pro. This program is reportedly the most efficient program on the market when it comes to noise reduction, and a cheap investment. DxO profiles all camera models supported by the program, making the program automatically find exactly the noise form of your camera. By knowing more about the noise, the software can also fix more of the noise while preserving details. In addition to noise reduction, the program is awesome when it comes to sharpening and lens corrections. If you've missed DxO Optics Pro, you should try the test version.
Do you think that you need a better camera to take photos at higher ISO? Are you sure that you really push your camera to the outermost? Instead of spending money on new equipment, you should get to know the equipment you already own. Rather spend your money on a more advanced program that does a better job with noise reduction.