[juanodaxis]

Hi all.
First of all, I'm not sure if I supposed to post this in here.
I got a second hand Minolta Dynax 500si Super, with a Sigma Zoom 28-80mm.
This works great, and I'm really happy about it; also, I don't know if this suppose to be a decent set-up for 35mm film camera.
My problem is that I also have a second hand Sigma Zoom 75-200mm, but this lens don't seems to want to work.
I get a lovely picture from the viewer, the zoom and focus works great manually, but the camera won't shoot, and the camera's display won't show any options at all.
When I switch the camera off, this lens gets a little burst of life as the power turns off.
I'm wondering, is this an incompatibility issue? Or the lens is toasted?
Any ideas?
Thanks.