A75 Manual (P) mode help

[ksc]

I am just starting to experiement with the manual features on my A75 and everytime i try to take a macro shot with the selection on (P), My picture comes out very grainy. This is the only mode i am having trouble on. Any ideas? I tried to attach a sample pic so you guys could see it, but it was too large. I will have to find another way to get a pic to you.

Thanks