It looked to me that the tip of the ball was kissing the white line, so if it's me, I'm signaling first down and moving the chains without a measurement.
But yeah, if you're measuring, give it a good look and if there's no discernable space between the ball and stick, give them the first down and go on. You're the only one with the perspective to know.
You may be ignoring, hopefully not missing, a very significant circumstance. Sometimes what we do,
especially if we routinely do it extremely well, can be misunderstood as being cavalier and we need to be careful it doesn't appear "ho-hum".
Jim Tunney relates when talking to John Madden after Oakland's Super Bowl, asking why he received a commemorative watch, and Madden got a ring, Tunney described as "with a diamond the size of an ashtray" Madden responded, " because he (Tunney) didn't care who won".
Not exactly accurate, but basically true and sometimes how that real close measurement turns out means a lot more to others than it does to the referee measuring, so you may want to treat it with the concern and importance others perceive, and attach to it, rather than what you know, "is what it is."
Being right, and others believing and accepting you're right, can be very different things, worth a little extra effort.