First response ovulation tests?

Can someone tell me about them? I just wanted to know if I was at risk of ovulating - I kind of ovulate at different times, it's not always the same. So I was just curious if anyone knew like how long to wait before urinating to take a test and if you get a light line, I know you are not supposed to count that as a positive test, but could it mean that ovulation would be coming soon if you saw a line? The tests I have say you can have a line or not have a line and it should be the same color to indicate a LH surge. But wouldn't a ligther line mean the LH surge is coming?