canon 20d indoor setting for kids music concert

I have a canon 20d and 28-135 IS lens

can anyone tell me what the best setting for taking pictures indoor with low light?

my kids had their music orchastrad in the highschool auditurium with low light.

I had took pictures with flash and in auto mode but the pictures came out too bright.

and also had took pictures with the dial turn to no flash but the pictures turn out dark.

what the best setting for the 20d?

should i used auto or manual?

how about setting for ISO and aperture?

 

thanks

Do you have an example picture to give us an idea of the venue? It's the best way solicit useful feedback.

A couple of images from the last effort would assist.

 

A general guide for a beginner to get the most keepers, shooting without Flash in a low light concert with that gear:

 

Preparation:

 

1. Select: ISO = ``H`` - which you have to allow, via Custom Functions.

 

2. Select: ``P`` - Program Mode

 

3. Select: Centre Weighted Metering

 

4. Select: Single Shot (not Continuous Shooting)

 

5. Select: One Shot AF - (not AI Focus or AI Servo)

 

6. Select: Centre Point AF only (not all the AF points)

 

***

 

Shooting:

 

1. Get as close to the action as possible and use the lens at the wider end of the zoom (wide angle end), as much as possible – but obviously not at the expense of using the telephoto end zoom, if you absolutely have to.

 

2. Have the main subject in the Centre of the Frame and ensure the red centre AF sensor is on a well lit, and contrasty area of that subject.

 

WW