Hard to tell from these pics, but judging by the web it is an orb weaver & not a false widow (in fact the photos rule out a false widow), possibly a missing sector orb weaver, but better pictures are really required for an ID - not that I don't like the pictures, very artistic, just not good from an ID point of view! ;-)
Thanks Mark! Sorry about the quality, but it was a photo shoot few months ago. For me spider is a spider. One is big, another is small, but now when everyone is panicking I just wanted to know. I'm safe now - and definitely not opening my windows!