50mm 1.8 problem? or is it?

I recent bought a 50mm f1.8 i don't know if its me or anyone else but for some reason its very sharp at f3.5 and f4.0 but soft at f1.8... is it me or do anyone have the same prob? if so is it normal to be alittle soft at 1.8 ? or do I need to take it back for a good copy?

it is very normal for a lens to be sharper when stopped down. it is also normal for a lens to be a bit soft when used wide open. also, make sure that you are not confusing razor thin DOF with softness. a lens with a 1.8 will have very minimal DOF so most of the frame will appear to be OOF.

Yes, mine didn't get sharp until about 2.8 or higher. That is really to me, the significant advantage of moving to the 1.4. Its not that I really needed the difference between 1.8 and 1.4, but the 1.4 gets sharper much earlier and is far sharper (in my experience) at 1.8 or 2.0 than is the 1.8 lens.

Yes, one of the drawbacks of the f1.8 vs the f1.4 is the softness wide-open. I still wouldn't give mine up for any money, and think it's an excellent value for the low price.