It's always worth backing up with a ClearBlue digital when you're close to getting a positive.
Last night my internet cheapie looked like it was very nearly dark enough but not quite where the ClearBlue gave me a smily face.
The photo you posted definitely looks negative to me. The test line needs to be as dark as the control. It can be hard to tell. Just yesterday I was posting a pic of my OPK to get some other views on it (I've got to the point where I can't tell what I'm actually seeing from what I want to see!).