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Explain this space rocket launch vid

Azrael 5 said:
Couldnt find a place to put this.
Saw this linked on Cluesforum,(it's fake obvs ;) )wanted someone with intelligence to explain the odd TV vs Live picture delay as it's bugging me. All seems to be out of sync with each other.
http://www.youtube.com/watch?v=D-f3wXAnjgE
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Accumulated delay in the broadcast path, camera to studio to cable distributor to TV (and any other steps I might have missed). None of those signals are instantaneous, and if they're being bounced off a satellite or two, they can be significant.

Have they ever spoken to someone in the same room as they are, but on a cell phone? There's quite often a noticeable delay in the voice transmission. That's the same effect at work, on a smaller scale.


Of course, Clueless Forum doesn't believe in satellites, so they'll discount this explanation out of hand.
 
I have two tv's within 15 feet of each other, and when tuned to the same channel, the audios have a lag. Most likely the videos would also.
Both have separate cable boxes.
 
On cable systems that have both digital and analog channels there is as much as s 5 sec delay between the same station's dig and analogue channel. This is due to the heavier processing in the digital realm. There is also a difference between pvr digital receivers and non-pvr units.
 
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If one tv uses hdmi input and another uses RGB there will be a difference. If they are made by different manufacturers they won't be the same. If one is lcd and the other is plasma they won't be the same.
 
For the OP, the launch was real. That old Minuteman booster really kicks off the pad, eh?

Not such a gentle ride... (and as for cluelesss forum, don't know if anyone over there understands the least bit of how spaceflight works...)
 
mrbusdriver said:
For the OP, the launch was real. That old Minuteman booster really kicks off the pad, eh?

Not such a gentle ride... (and as for cluelesss forum, don't know if anyone over there understands the least bit of how spaceflight works...)
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The sad part is, they do have one guy....but it's Heiwa....and the rest ignore him.
 
mrbusdriver said:
For the OP, the launch was real. That old Minuteman booster really kicks off the pad, eh?

Not such a gentle ride... (and as for clueless forum, don't know if anyone over there understands the least bit of how spaceflight works...)
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Of course it was real! I never doubted it,just didnt understand time delays with satellite but now it make sense. I actually recall watching a football game whilst on phone to a friend watching same game and a team scored on my TV before his!
Memory not good these days ;)
 
I believe they often have a deliberate lag in case something goes horribly wrong and they can cut the live feed. Often done with live broadcasts
 
Montag451 said:
I believe they often have a deliberate lag in case something goes horribly wrong and they can cut the live feed. Often done with live broadcasts
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Yes but not likely used on a rocket launch. There's no particular danger of someone dropping an f-bomb or reporters performing a nip-slip. Deliberate delays for such things are a pain in the ***.

What is seen in the video, even if the TV feed is from a local channel is due to video stream processing. You have several cameras and other video sources(such as playback source) , graphics insertion, plus transmission delay on cable lengths. In modern digital systems your stream is often in SDI format with embedded audio. This must be transferred to a format that the cable or DTH satellite channel uses. Cablecos now use a lot of fiber, yet another delay in processing to convert to laser transport, then(usually) in the last mile its converted back to coaxial cable and digital transport stream, to your cable box, converted to the format the TV recognizes (ie. HDMI).

THAT is what is demonstrated in the OP. If the feed is from CNN or any non-local station it may well have been uplinked to satellite, downlinked to the Station's Master Control, graphics and voice over added, uplinked again, thence downlinked by the cableco etc...

One other problem is getting the audio to remained synced to the video since audio receives a lot less processing (not as much information to deal with as in video) it can pass through much quicker than the video. This requires inserting delay in the audio to remain in sync with the video
 
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jaydeehess said:
THAT is what is demonstrated in the OP. If the feed is from CNN or any non-local station it may well have been uplinked to satellite, downlinked to the Station's Master Control, graphics and voice over added, uplinked again, thence downlinked by the cableco etc...
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Well-explained, grasshopper. :)

I've always found it interesting to compare signal delays between stations when something of particular note is being carried across the board (ie Obama giving a speech of note). I've seen about a 2-second difference between (IIRC) NW & CTVNN.

It's astonishing how CTers seem to live for a lack of understanding to propel their CTs. Kind of sad though

Fitz
 
Azrael 5 said:
Of course it was real! I never doubted it,just didnt understand time delays with satellite but now it make sense. I actually recall watching a football game whilst on phone to a friend watching same game and a team scored on my TV before his!
Memory not good these days ;)
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I remember years ago, watching the World Cup in a pub with some colleagues and "predicting" that someone would miss a goal attempt because I could see a second screen that was (for some reason) about twelve seconds ahead of the one we were watching.
 
fitzgibbon said:
Well-explained, grasshopper. :)

I've always found it interesting to compare signal delays between stations when something of particular note is being carried across the board (ie Obama giving a speech of note). I've seen about a 2-second difference between (IIRC) NW & CTVNN.

It's astonishing how CTers seem to live for a lack of understanding to propel their CTs. Kind of sad though

Fitz
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Indeed, and one instance recently was surprising. That Voice on the Canadian feed was leading the American network.
 
catsmate1 said:
I remember years ago, watching the World Cup in a pub with some colleagues and "predicting" that someone would miss a goal attempt because I could see a second screen that was (for some reason) about twelve seconds ahead of the one we were watching.
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If the one you were watching came from a pvr revceiver its quite possible that someone had paused it for 12 seconds before the game began. It would continue to be 12 sec behind reality until told to skip to live play or someone changed the channel.
 
jaydeehess said:
If the one you were watching came from a pvr revceiver its quite possible that someone had paused it for 12 seconds before the game began. It would continue to be 12 sec behind reality until told to skip to live play or someone changed the channel.
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That's actually a really good point, that happens occasionally in my house when Mrs. LSSBB pauses one of her shows.
 
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