concert - Blown out blue/red light making photos look out of focus

I've only recently started taking photos and got into shooting concerts in a small venue that has neither a pit, nor proper lighting. All they use is some kind of simple LED array.

The thing is nobody wants to operate the lights and they tend to be too strong (I think).

Sometimes it's just like that for 15 mins or something... Photos seem to be out of focus, but I'm 99% sure they are (you can never be sure with a Nikon D7000, though).

These were shot using the 35mm DX and then cropped. Sometimes you can get something out of these kind of photos in LR (luminance, clarity), but it mostly looks like you f*ed up...

What can I do about it, except waiting for the light to change?

Underexposing will lead to heavier post-processing, which is unacceptable and B&W looks ugly and not sharp...

Of course not every photo has to be a keeper, nonetheless I'd like to know how to deal with that.

edit to explain(...)

Not exactly a duplicate, because I'm not using aperture priority so metering problems don't apply here. Different colour of light (green) + same settings, and the photo is fine. I'm aware of light waves having different lengths, etc. Just asking whether I should underexpose or it's just the way it is.

Answer

The general fuzziness and lack of detail in these photos is mostly due to being lit primarily by one strong color.

Your camera's sensor has what is called a Bayer color filter array on it which allows it to record only one primary color per sensor element. In your camera or raw processing software, the single-color-per-pixel sensor data is combined to produce a full-color image.

Important to your situation is the fact that for each set of four sensor elements, two are green-sensitive, one is red-sensitive, and one is blue-sensitive.

Knowing that, it's easy to see that when your subject is lit only by strong red light, you're only recording image data with 1/4 of the sensor elements on your sensor. The remaining 3/4 of the data has to be interpolated and most interpolation algorithms aren't going to do well without any green- or blue-channel information. That results in a blurry image lacking in fine detail.

Unfortunately there's no good way around this with traditional color-filter-array sensors. A Foveon sensor would excel in situations like this, as all its sensor elements are sensitive to all colors. Color film would also not suffer this problem.

It's also worth noting that this is a very good reason not to use color contrast filters (intended for black-and-white film) on a digital camera.