Originally posted by yozza Edgar if i am shooting full body versus head and shoulders would you still go with these over a 50?
If I could only choose one prime lens for people pictures, then I'd go with a true portrait lens like the 77 or 85mm. Reason being is that you can use the same lens for full body shots or for head shots. True, you have to back up a bit for body shots, but if you want to do any tight head shots with a 50mm then it's not the most flattering focal length.
The obvious solution to this dilemma would be a zoom. The Pentax 24-70mm would be great, but there are also some much cheaper alternatives that are also nice performers, such as the Tamron 28-75mm f/2.8 or the Sigma 24-70mm f/2.8 (I've used and enjoyed the Tamron, but I can't vouch for the Sigma). That's probably the direction I would go for event shooting. The wide end would let you do group shots, the mid-range would be good for full-body, and you can zoom in for tight head shots.