VGA Conversion

[Herr_Sprecker]

Greetings all. I am getting ready to design projections for a show. The set is going to include 8 monitors installed within the set structure at random locations. Some of these monitors are going to be standard TVs with a coax input (no RCA that I am aware of), and others are going to be computer monitors. We're using them this way because it's what we have, and the different types of screens fits within the scenic concept for the show.

Getting the single video signal split into 8 outputs isn't my challenge right now, given the nicely available 8-way splitters available commercially. However, the conversion for some of these monitors from VGA to Coax or such is going to be a bit more challenging. At this point, I do not think it will be possible to go to a single type of input as we simply do not have enough of that kind of monitor available. So, what are some solutions for decent conversion of the VGA signal into a coax or RCA connector without significant image degradation. Just as an FYI, these monitors are going to be showing rapid bursts of images and video, and their size and relative distance to the audience means that a little degradation is acceptable so long as it doesn't constitute incredibly wavy lines or such.

Any thoughts or ideas would be greatly appreciated. Thanks!

 

[SHARYNF]

Hi I would suggest that you run two feeds depending on the type of monitor For the vga to standard video IF you have a standard video in (rca) I would use one of the Extron type units http://www.extron.com/download/files/brochure/vsc100ebro.pdf

If you only have antenna in ( assuming it is a tv) then you could get one of the rf converters.RF Modulator : Converters | RadioShack.com

For vga you could use a VGA splitter VGA Splitters: Split/extend up to 210 feet; up to 8 ports; with or without 3.5mm audio; also y-cables - Cables To Go

These are just suggestions, the quality varies (the extron is good quality)
Another approach is that many video cards in your computer have the option for standard video out, which also might be an option

Sharyn

 

[museav]

Another consideration but are all displays the same format, for example all 4:3 or all 16:9 widescreen? If you start mixing formats things can get more complex unless the widescreen displays can internally 'stretch' a 4:3 format image.

Sharyn hit in the main point which is that if you have VGA and antenna inputs then you are dealing with two quite different signals that could involve multiple conversions, for example splitting the VGA signal to get multiple outputs one of which runs into a scan converter to be converted to composite video which then runs that into an RF modulator the output of which is split to multiple displays.

The signal degradation experienced will depend on the quality of the components, the amount of processing required and the quality of image you start with. For example, as the conversions involved result in a limited resolution image, thus a 640x480 resolution image might experience less degradation through the path noted above than a higher reolution image. There is simply no way to get a high resolution signal down to NTSC video without losing something and the more that has to be lost, the greater the resulting degradation.

You might also want to think about the power and cabling involved and how all that will be accommodated in the set as you may need to start planning on the cables and other equipment that may need to be purchased to get everything working.

 

[Herr_Sprecker]

No worries about mixing display format. In fact, the director made my life considerably easier by deciding to use all TVs instead of a mix of different devices. So, now I am looking at 8 TVs, all with a coax input, which will make the powered distribution easier. So, now I will just need to convert a VGA signal into a Coax one time. I know that the video card I will be using only has VGA out, no capacity to change it for something that might have an RCA video or S-Video.

So, the shopping list is now for a really good converter from VGA into Coax. Any suggestions?

 

[ruinexplorer]

What kind of price range are you looking for?