double/triple exposers and delay/phase processors

[relicmarks]

What processor can delay or phase shift the video signals?

What processor can take a Signal video source signal and create
double/triple exposers?

If i have a VCR or DVD player and use a video splitter that splits its 3 or 4 ways having 3 or 4 outputs how can i delay or phase shift the video signals so they create multiple exposers overlapping please?

What causes flicker or strobing video signals?

What processor can cause a video signal to flicker or strobe? (variable shutter speed) but how can i take a pre-recorded video signal and ADD shutter/flicker what would cause or do this please?

And Yes i know digital video mixers do flicker or stobe but how did ANALOG video mixers do this what type/kind of circuit/network would generate a flicker/strobe circuit/network? its like a On/off pulsing circuit but what kind?

Most digital video mixers i read about don't do double or triple exposers how did they do this

What is the theory behind Analog video mixers? the circuit block diagram
1.) inputs mixing section ( i understand)
2.) The crossfading section ( i understand)
3.) What else is inside a video mixer in sections please?

Would a TBC create time delay video signals to create double or triple exposers but how please?

What TBC processor has a FEEDBACK LOOP so i can feedback the output to the input

What Video processor creates video Delay signals? that has a "feedback loop" so the processors output feedbacks to the input? what would do this please for video signals?

[RFBurns]

What processor can delay or phase shift the video signals?

Some frame sync units can add delay to video for timing purposes, or you can use what is called a video delay box that is either pre-set for a specific amount of delay or switchable to select various amounts of delay. The frame sync and or TBC can perform the phase shifting usually controlled by an adjustment knob on the unit.

What processor can take a Signal video source signal and create
double/triple exposers?

This kind of effect is accomplished with a memory bucket brigade, similar to an audio bucket brigade array. In the past, it was done through an effects unit that utilized early write-hold-read memory boards consisting of rows of 1meg memory chips. It usually took several of these boards that held up to 50 or more 1 meg chips.

You could use the video delay boxes to accomplish this too, but keeping your color phases and frequency responses intact is very difficult when daisy-chaining video delay boxes to produce several outputs, each with a delay as the signal travels down the line.

If i have a VCR or DVD player and use a video splitter that splits its 3 or 4 ways having 3 or 4 outputs how can i delay or phase shift the video signals so they create multiple exposers overlapping please?

Again using the video delay boxes either fixed or switchable delay times can accomplish this. But keeping color phasing in between the delay points and frequency response so the signal doesnt look faded or washed out is another huge task. It can be done this way, but not easy.

What causes flicker or strobing video signals?

Usually done with an effects box or digital effects generator. In the analog world various circuits would give the effects of flickering old film look and strobing.

What processor can cause a video signal to flicker or strobe? (variable shutter speed) but how can i take a pre-recorded video signal and ADD shutter/flicker what would cause or do this please?

See answer above.

And Yes i know digital video mixers do flicker or stobe but how did ANALOG video mixers do this what type/kind of circuit/network would generate a flicker/strobe circuit/network? its like a On/off pulsing circuit but what kind?

Various designs accomplished this. Some would use a slice of quartz crystal which when a voltage is applied to one end, it would arrive at the other end with a slight delay time. By switching this in and out of the signal path, you can get a strobe effect or old film flicker effect. Another way is to simply apply the video signal through a fast switching transistor that is triggered by a timing generator or pulse generator that has an adjustable pulse time/width function. This would simply turn off and on the video signal to give the flicker effect. However the circuit would maintain your sync and color burst signals, it only switched the video information itself.

Most digital video mixers i read about don't do double or triple exposers how did they do this

By adding an option module to the mixer or sending the signal to an outboard piece of equipment.

What is the theory behind Analog video mixers? the circuit block diagram
1.) inputs mixing section ( i understand)
2.) The crossfading section ( i understand)
3.) What else is inside a video mixer in sections please?

You can find detailed info on analog video mixer/switchers at websites such as Grass Vally Corp. or going to either the NAB or SBE websites where you can get all kinds of detailed information.

Would a TBC create time delay video signals to create double or triple exposers but how please?

What TBC processor has a FEEDBACK LOOP so i can feedback the output to the input

What Video processor creates video Delay signals? that has a "feedback loop" so the processors output feedbacks to the input? what would do this please for video signals?

Some TBC's can delay a video signal but I have never seen a TBC perform multi-exposures that are independantly delayed.

Why would you want to feedback loop the output to the input?

The only processors that provide delay are the ones I mentioned above, both preset delay boxes and selectable delay boxes. There are digital effects generators that can delay the video too and if your lucky, you can find the old analog stuff that can do the same thing.

Feeding back a video signal to the input would give you a nice blurred, white-out smeared image. Just like an audio signal being feed back to an input, but you wont "hear" the squeal, you would "see" the results on the screen. An effects generator can do this safely and with better results if the smear effect is what you are looking for.

I suggest purchasing a copy of the engineering handbook which goes into great details about all of your inqueries. There are other publications too that dive into details of video switchers, mixers, effects generators and such. These publications can be found almost anywhere. Try using "video effects equipment" as a search word.

[relicmarks]

Thanks alot for your information and time

these Video engineering handbooks what are the names of them i went on amazon.com and i can't find any which names/authors do u have or know about that i need please


1.) who makes these "video delay boxes"? what are they called please?

2.) I'm trying to find a video delay boxes that is 1sec to 5seconds or more
so i get overlaping video and video offseting superimposing images

3.) it will look like this:

http://www.amazon.com/Piper-at-Gates-Dawn/dp/B000002UA0

Pink floyds piper at the gates of gawn album

4.) Does the TBC "hue parameter" is controlling zero degrees to 360 degrees phase shifting?

5.) Roland has a V-4 video mixer its a A/B bussing mixer but doesn't have AUX channels how can i hook up external special effect generators to it please?
What kind of box would have AUX channels external that i can hook up to the video signals so i can processor the video signals with external special effect generators?

[RFBurns]

Thanks alot for your information and time

these Video engineering handbooks what are the names of them i went on amazon.com and i can't find any which names/authors do u have or know about that i need please


1.) who makes these "video delay boxes"? what are they called please?

2.) I'm trying to find a video delay boxes that is 1sec to 5seconds or more
so i get overlaping video and video offseting superimposing images

3.) it will look like this:

http://www.amazon.com/Piper-at-Gates-Dawn/dp/B000002UA0

Pink floyds piper at the gates of gawn album

4.) Does the TBC "hue parameter" is controlling zero degrees to 360 degrees phase shifting?

5.) Roland has a V-4 video mixer its a A/B bussing mixer but doesn't have AUX channels how can i hook up external special effect generators to it please?
What kind of box would have AUX channels external that i can hook up to the video signals so i can processor the video signals with external special effect generators?

I dont think you will find much at amazon, however check out the NAB website for them. www.nab.org


Running a google search for "video delay" gave numerous links to various manufacturers of video delay units. There are active and passive delay units as well as adjustable units. Give it a try.

Most TBC and Frame Sync units can adjust chroma phase by as much as 50 percent from reference center, ie +25% and -25%. To achieve a 360* phase shift is somewhat overkill, and rarely ever encountered in the field. Once you begin a 360* shift, by the time it hits the tail end of the signal path, your luminance vs chroma will be just that, 360* out of phase.

The way to get effects gear in and out of a mixer with no aux send/return ports is to use a router. An 8x8 router for example, gives 8 inputs and 8 outputs and you can route any of the 8 sources to any of the 8 destinations. Some will even combine and split signals.

So for example, we want to have a wave effect on a camera signal before it hits our mixer. The camera signal is routed to the effect generator via the router, and then the effect generator's output is routed to an input on the mixer via the same router. Lets also run that camera signal direct to our mixer via the router for a "clean" signal. We simply tell the router to send the output of the effect generator to an input on the mixer, and route the camera signal to another input on the mixer. We now have a direct signal from the camera itself thru our mixer as well as that same signal being fed to the mixer from the effects generator. We can then mix or "hotpunch" between the two to see the differences.

Router systems can be daisy-chained to provide as many inputs and outputs as you might need. A typical production house or broadcast tv facility might have a 250x250 router or even higher. Some facilities will have multiple routers that are configured to be isolated from each other, but can be linked via the RS232 ports so that at any given time, one or more of them can be combined to route signals where they need to go even tho the systems are isolated. It just depends on the configurations and requirements of the facility in question as to what kind of routing system is needed.

For example, lets take a super bowl scenario, where there are up to 50 or more field cameras, each with a monitor feed, IFB feed and return feed. Each of these cameras can also be feeding their own recorder, along with the signal being routed to a huge production switcher, which is also being feed CG signals, and feeding all that into 100 different transmission points, ie satellite feed, microwave feed, monitors for the press rooms, owners, and the huge screen up in the stands. A system of this type would probably have up to 10 independant router systems that may support a 128x128 or more configuration. Along the way, we have distribution amplifiers for each input signal and EQ compensation for cable lengths. Plus having Proc-Amps helps us keep our sync signals in check along with several "black" or house sync generators all syncronized to a master/slave backup house sync generator. Those too must be routed to each camera, each reference monitor, and to each transmission point. We also must be able to route in and out the "replay" units so that when that big play is made and we all missed it or it occured during a commercial, the replay playback signal can be routed to the switcher and punched up on air. Ever wonder how they are able to catch things and play them back from the various camera angles? It is because each camera out there is also feeding an independant recorder in the "raw" form, in other words, there are 50 recorders looking at the 50 cameras without going through the switcher. That way no matter what the director punches up on the switcher for us to see on our tv's, whatever the cameras are looking at, each one is being recorded full time and independantly.

The director punches up the appropriate recorder for a given replay and the replay tape operator cues up the recording to the point of interest.

Hope this helps a bit.

[relicmarks]

Thanks again for your time and information

Ok i did find the video delay units now thanks

1.) How did they do double/triple exposure using optical printers or video signals back in the day? i need some theory about how they did it so i can learn from please? how would they route the video signals or signal paths ? would they use routers to split the video signals to go to multiple video delay units?

2.) luminance vs chroma will be just that, 360* out of phase.
I'm still confused about chroma phase shifts and luminance phase shifts

What are the chroma phase shift angles? 0 degrees to what please?
What are the Luminance phase shift angles? 0 degrees to what please?

3.) when using the Vectorscope how do you know if the Luminance VS Chroma are 360 degrees "out of phase"?

4.) when using the Vectorscope how do you know if the Luminance VS Chroma are 360 degrees "IN of phase"?

5.) when using the Vectorscope how do you know if the Luminance VS Chroma are 90 degrees "out of phase"?

6.) when using the Vectorscope how do you know if the Luminance VS Chroma are 90 degrees "IN of phase"?