Lens for portraits?

My family is wanting me to make some portraits of the whole family this christmas and I want to get a decent lens to do it with. What is a reasonably priced lens that will give me good results? Any suggestions will be greatly appreciated. Thanks.

50mm 1.8 / 1.4, 85mm 1.8.

sigma 17-70

50 1.4 / 50 1.8
85 1.2L / 85 1.8
24-70L / 24-104L

how big is the room where you will take the photo, if its indoors and you want to fit everyone into the frame you will need a wide angle, within the 10-30mm range

if you can step back a lot the 50 or 85mm lenses are a good option

If money is no object and you want head and shoulder portraits, I would get the 85 f/1.2 L, for a reasonable lens the 85 f/1.8 will work great. If you want group shots or full body shots, I would look at the 28 f/1.8, the Sigma 30 f/1.4 or the Tamron 28-75 f/2.8.

They are all good lens.

Thanks, those are some good options for me. I will now have to find some pictures from all of them for comparisions. Thanks again.

What camera would you be using? Full frame or 1.6x ?

Full frame 85mm f1.2 L, if its a 1.6x sensor, then the 50mm f1.4.
The lenses are recommended for single or double subject portraits.
For larger groups it would mean a greater distance between subject and camera. Then the choice of lense focal length would change. Under such requirements, I would use the 135mm f2 L. It is expensive, but superb.

Study some of the excellent galleries you see on this website and you will get some better idea of your lens choice.

The 50 1.4 and your 30D would be great! Or, wait for the new 50 1.2 to reach the stores.