# The First-Down line in football broadcasts... **URL:** \ **Category:** Factual Questions\ **Created:** [November 27, 2001, 3:24pm UTC](https://boards.straightdope.com/t/the-first-down-line-in-football-broadcasts/95505 "2001-11-27T15:24:53Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![papasmurf](https://avatars.discourse-cdn.com/v4/letter/p/90ced4/32.png) [@papasmurf](https://boards.straightdope.com/u/papasmurf)\ **Post date:** [November 27, 2001, 3:24pm UTC](https://boards.straightdope.com/t/the-first-down-line-in-football-broadcasts/95505/1 "2001-11-27T15:24:53Z")
How _exactly_ do they superimpose the yellow line over the field during broadcasts? A few specific questions: (1) Is there some sort of “beacon” attached to the first down marker on the side line which is then extrapolated to a line across the field? (2) Can they do this from all camera angles, or does it require a specially equipped camera (or one that doesn’t change field angle)? (3) How come the line is underneath the players when they pass over it, but remains on the green grass and white chalk (but doesn’t appear on the white pants of the players?) I presume this is analagous to “green-screen” technology, but I don’t quite get why it works when the players share some of the same colors as the field. Thanks! -ollie- ---
**Author:** ![Klaatu](https://avatars.discourse-cdn.com/v4/letter/k/e0b2c6/32.png) [@Klaatu](https://boards.straightdope.com/u/Klaatu)\ **Post date:** [November 27, 2001, 3:50pm UTC](https://boards.straightdope.com/t/the-first-down-line-in-football-broadcasts/95505/2 "2001-11-27T15:50:21Z")
A great explanation can be found [here](http://www.howstuffworks.com/first-down-line.htm) ---
**Author:** ![St.Urho](https://avatars.discourse-cdn.com/v4/letter/s/8e7dd6/32.png) [@St.Urho](https://boards.straightdope.com/u/St.Urho)\ **Post date:** [November 27, 2001, 4:19pm UTC](https://boards.straightdope.com/t/the-first-down-line-in-football-broadcasts/95505/3 "2001-11-27T16:19:12Z")
For some more information, you can also check out the company’s website at htpp://www.lovetheline.com ---
**Author:** ![The\_Great\_Gazoo](https://avatars.discourse-cdn.com/v4/letter/t/67e7ee/32.png) [@The\_Great\_Gazoo](https://boards.straightdope.com/u/The_Great_Gazoo)\ **Post date:** [November 27, 2001, 6:15pm UTC](https://boards.straightdope.com/t/the-first-down-line-in-football-broadcasts/95505/4 "2001-11-27T18:15:23Z")
> [@](#): > > \*Originally posted by Klaatu \* > \*\*A great explanation can be found > [here](http://www.howstuffworks.com/first-down-line.htm) \*\* I advise people to stay away from [howstuffworks.com](http://howstuffworks.com) until they figure out that popup windows are unnecessary. It’s almost as bad as a porn site (from what I hear about porn sites, that is) ---
**Author:** ![Hail\_Ants](https://avatars.discourse-cdn.com/v4/letter/h/dc4da7/32.png) [@Hail\_Ants](https://boards.straightdope.com/u/Hail_Ants)\ **Post date:** [November 27, 2001, 10:11pm UTC](https://boards.straightdope.com/t/the-first-down-line-in-football-broadcasts/95505/5 "2001-11-27T22:11:40Z")
Actually, the company’s web site is [http://www.sportvision.com](http://www.sportvision.com) Just get [Pop-Up Stopper](http://www.zdnet.com/downloads/stories/info/0,10615,66880,.html) and [HowStuffWorks.com](http://HowStuffWorks.com) (and others like it) is fine. ---
**Author:** ![The\_Great\_Gazoo](https://avatars.discourse-cdn.com/v4/letter/t/67e7ee/32.png) [@The\_Great\_Gazoo](https://boards.straightdope.com/u/The_Great_Gazoo)\ **Post date:** [November 27, 2001, 10:20pm UTC](https://boards.straightdope.com/t/the-first-down-line-in-football-broadcasts/95505/6 "2001-11-27T22:20:59Z")
Nope - Popup stopper and their ilk are great as far as they go, but companies need to understand that popups are not welcome. Neither are cookies. Most companies have figured out that cookies are unwelcome, but haven’t figured that out about popups yet. Just like telemarketers - if no one buys this crap, they will get rid of it. ---
**Author:** ![Flymaster](https://avatars.discourse-cdn.com/v4/letter/f/c4cdca/32.png) [@Flymaster](https://boards.straightdope.com/u/Flymaster)\ **Post date:** [November 27, 2001, 11:35pm UTC](https://boards.straightdope.com/t/the-first-down-line-in-football-broadcasts/95505/7 "2001-11-27T23:35:56Z")
In the interest of not hijacking this thread, Gazoo, please join me in the pit. [http://boards.straightdope.com/sdmb/showthread.php?threadid=101247](http://boards.straightdope.com/sdmb/showthread.php?threadid=101247) ---
**Author:** ![Reeder](https://avatars.discourse-cdn.com/v4/letter/r/c6cbf5/32.png) [@Reeder](https://boards.straightdope.com/u/Reeder)\ **Post date:** [November 28, 2001, 2:20am UTC](https://boards.straightdope.com/t/the-first-down-line-in-football-broadcasts/95505/8 "2001-11-28T02:20:32Z")
To stop popups, you don’t need another program, just turn off javascript in your browser. ---
**Author:** ![Hail\_Ants](https://avatars.discourse-cdn.com/v4/letter/h/dc4da7/32.png) [@Hail\_Ants](https://boards.straightdope.com/u/Hail_Ants)\ **Post date:** [November 28, 2001, 4:46am UTC](https://boards.straightdope.com/t/the-first-down-line-in-football-broadcasts/95505/9 "2001-11-28T04:46:04Z")
Yeah, but turning Javascript off disables other, useful features too. Besides, Pop-up Stopper is freeware.