[Dabhand16]

Your lens does have the ability to be able to work in lower light levels than 'slower' lenses, but it is not just a question of fitting it and banging off your shots.

As Navarroe said, you still have to consider what depth of field you need and that might well mean that you will have to stop down from the maximum apature. If this means that you are going to underexpose the shot and you do not want to use a flash, you will have to raise the ISO. When it is wide open and used at fairly close range, I suspect your lens might only have a depth of field of about an inch

Rather than just playing with the lens, do some consructive tests - take some shots from a fixed viewpoint starting with it wide open and then reduce the apature on sucessive shots. This way you will see the depth of field that is available at different settings.

It is not a good idea to put equipment in boxes and think of 'this lens is for use indoors with no flash' or 'this lens is for taking family portraits'. You can use this, and any other lens, in any conditions and for any subject you like, because different lenses will give different results - for instance, telephoto lenses will compress perspective, and 50 - 85 mm lenses are ideal for portraits - but you still have to make the appropriate adjustments to capture the picture you want.

If your camera has a depth of field preview button it will enable you to check before the shot if you are not shooting action.