Resolution question

[dbuckley]

OK, beginners question time.

 

Lets assume (if I weren't as old as time itself, this would be a homework question) I'm hiring a led screen with an "odd" aspect ratio, 384 (w) x 168 (h) LED pixels, how do I make this work? Being as I'm in NZ and choices are limited, if this goes ahead it'll probably be Element Labs Cobra 16 panels, as thats what we seem to have available here. Anyone know how these are wired up? A bit of googling has failed to find a manual, presumably because this mob got gobbled by Barco, just this old spec sheet (PDF).

 

I assume that eventually, I get presented with a VGA cable to plug into my (screen monkey) computer's second VGA port. So, and in particular, what resolution should I set the second video out to? Is it something "normal" that gets scaled, (like 1024 x 768) or should I make it the same as the screen native resolution, and if so, how?

 

If the computer is set to a normal resolution that doesn't naturally fit the target screen aspect ratio, wont that screw up the aspect ratio of pictures and video? Or do I restrict myself to just a bit of the screen??

 

It all seems very different from just throwing up a projector.

 

Thanks in advance for any sage wisdom on the subject.

[mac.calder]

Normally there is a video processor before the video wall that you send a stock standard resolution to - what then happens is that you set the region of the input that is being sent to the wall - most systems will take the top left pixels by default, but most can be customised to take it from whichever region you prefer - including doing multiple regions to allow for black space between pannels.

 

Some systems will allow you to scale if you would prefer to as well.

[Ian H]

Firstly it is unlikely that processor will have a VGA input -- almost certainly DVI

 

1024 - 768 or 1280 - 1024 both suitable resolutions normally you just need to set an offset for where you place your content -- I normally use 50,50 or 100,100 that's from the Top Left of your screen....

 

I can put you in contact with the ex ELabs guys if you need more info....

[dbuckley]

OK, so its plan B then, so on the monkey I just use a little chunk of the overall screen size.

 

Thanks both.

[Kopy]

The video company would normally put some processing before the screen itself, such as a Barco ImagePro. This would allow you to fit your computer's full screen to fit the LED screen if that's what you want. If it's a different aspect ratio to your content it could be squashed or stretched to fit the screen if that's what you want. Basically it's up to you, the customer.

[sleepytom]

Possibly, though often these days a lighting company will send a screen out with some monkey who has no scaler and only a copy of LED Studio! That's if you get a tech at all.

 

Basically it is up to you the customer to insist on getting the correct kit to do the task you want to achieve. Probably a good starting point is using a well established video company, and selecting your supplier based on their skills, equipment and experience; rather than simply picking the lowest price!

[AHYoung]

I get a fairly regular call, saying a variation on "we are just starting a major tour with name act and cant get our video wall working, the lighting company we hired it off say we might need a thing called a screenpro but dont have any they can send and they arnt sure it will help, so can you send us one and tell us how to make everything work" nobody checks when you hire a dozen movers without that you understand patching and the basics of DMX, likewise you can hire a led wall without any understanding of video basics such as the fact that its generally dvi d only on the in without any scaling and you cant just use a passive vga - dvi adaptor or plug in a dvd player etc and your content needs to be the right size.

 

If you regularly use a LED wall, it may be worth getting yourself a TVone 750 scaler. Its a pretty cheap and fairly user unfriendly but adaptable little box that had 2 DVI I ins and and DVI I out. basically you can stick digital or analogue in and get either out, and it has all the scaling you need to make a video wall work. It will also take the output from your vision mixer if you mave the right wires. my advice would be to get an rs232 adaptor and programme it from your laptop as its no fun pressing the buttons on the front when the displays not working

 

 

http://www.tvone.com/1t-c2-750-main.shtml

[dbuckley]

Ha, so it seems it gets worse.

 

Based on what I had read above, and then what I found on the ScreenMonkey forum (here and here), it seems all I have to do is set the layer properties in SM to match the offset and width (in pixels) that the LED wall is set up for, and the aspect ratio will be correct. Obviously I have to make my content the right "shape" so it fits the wall sensibly.

 

Is this not the right way to do this?

[sleepytom]

it's one way to do it.

 

If your using the Element Labs screen then it depends how the Vizomo processor has been setup. I believe this is similar to the other EL processors and the screen can be mapped in various ways so it's nor always a case of it being a direct 1:1 pixel map. Speak to the people supplying the screen - they really should know how you need to work to get the content onto the screen. If they don't have this knowledge then I wouldn't rent a screen from them!

[dbuckley]

Thanks; The screen folks will be competent and then some, but I am just getting myself mentally prepared so I have a bit of background.