Converting to HD-SDI

[samsc]

on a side note... if you wanted to take the time to explain precisely how that few seconds of jittery video happens I would love to hear it from you Richard. The concept is simple enough however I am curious as to what happens with the buffers or whatever it is at that precise time. Understanding is power

another really really common thing-

is that people run multiple monitors out of a computer at different sizes and refresh rates-
sometimes they run a triple head and a single screen-

with this - the refresh rates are different to each monitor

vga/dvi have different refresh rates at different sizes-

for 60Hz its somewhere between 60.04 and 59.95

dvi and vga are not constant frame rates at different screen sizes.

then they do video input - at 25 or 29.97 -

an enormous number of possibilities - i try to do the best possible thing for these complex scenarios.

i found a vga frame rate calculator at :
http://www.tkk.fi/Misc/Electronics/f...2rgb/calc.html

[ajmaudio]

I get the metaphor.. I guess I was looking for more of a precise explanation of what happens in that jittery moment as far as the machine itself....why does it work fine, then jitter, then work fine again. its liek the cabbages line up for a bit then don't... or there is a buffer in there helping out that can only help sooo much or sumthin. Guess I am not explaining myself well. I get that they are different rates and all. I guess I figure if anything this would cause it not to work at all... not the work90 percent of the time.. then not.. then work again thing.

[samsc]

I get the metaphor.. I guess I was looking for more of a precise explanation of what happens in that jittery moment as far as the machine itself....why does it work fine, then jitter, then work fine again. its liek the cabbages line up for a bit then don't... or there is a buffer in there helping out that can only help sooo much or sumthin. Guess I am not explaining myself well. I get that they are different rates and all. I guess I figure if anything this would cause it not to work at all... not the work90 percent of the time.. then not.. then work again thing.

'jitter' isnt a sign of it not working -

its one of two things- 2 frames of video falling within a single screen refresh - or 2 screen refreshes within a single video input-

what happens with buffers - they add a delay- and then people complain about latency... but there are several buffers -

i give access to the buffer settings with frame rate settings- and you can make slight adjustments with these things to compensate for frame things-

you need to try different frame rate settings and see what happens.

[ajmaudio]

thank you for that explanation... makes sense. is it normal for this to occur for several seconds then clear up?

[samsc]

thank you for that explanation... makes sense. is it normal for this to occur for several seconds then clear up?

depends on your screen settings.
and some very specific timing things

did you manage to change the catalyst frame rate to be locked to the monitor refresh rate?

[SourceChild]

I'm in Australia and using a ton of ImagePros the video company provided. The thing is that I hate using the DVI input on an ImagePro with Catalyst, but I am using non standard images sizes that are normally supported by the analog components of the TH2G which I am also using.

In short, those of you who use TH2Gs know how much a pain it is to use ImagePros with Macs much less TH2G boxes. Obviously I would have been find if I had remembered my DVI detectives but I didn't.

What my question regarding this is how the TVOne Boxes stack up when it comes to TH2Gs. The video company is supposed to be bringing out some 2355s for something that came up but they are not here.

I am excited to get my hands on one to play with it. I am also curious too about the 7200s.

I'm probably going to order a dozen of these here soon so I want to know what pros and cons are.

Some of the issues I have already heard are the scaling and sizing issues they have when used as feeds for LED walls. What I was told by several of the LED techs who've used them is that they are great for converting and genlocking but once you begin to scale and size to a low rez wall, they aren't practical.

Any thoughts on this? I apreciate as much opinion as anyone can offer.

Thanks,

[prodigal2]

Todd

If you are only going DVI in and DVI out I would say that the Barco DVI 8x8 Matrix pro is the way to go. Its only drawback is its only a DVI switcher with programmable EDIDs per input.... but its far better solution than DVI detectives, and also means you can have a switching setup for backups.

the downside is there is no scaling or positional stuff, but in truth I really don't like doing that outside of catalyst with LED screens, as it usally means there is latency being added to the system and another point where disaster can bite your gig(lets just say extrons are BANNED on my gigs). And there is no genlock. But for DVI routing they are the business and the latency is a lot less than using a Folsom with DVI in and linking through.


Phil
Philip G Haynes
Live Visual Design and Direction

[SourceChild]

Eh Phil... The thread was "Converting DVI to HDSDI. I prefer staying DVI. In fact, I use fibre and a fibre router in my backup path. The clients I have though are all HDSDI and I pass through their switchers which means I have to Genlock.

[prodigal2]

Eh Phil... The thread was "Converting DVI to HDSDI. I prefer staying DVI. In fact, I use fibre and a fibre router in my backup path. The clients I have though are all HDSDI and I pass through their switchers which means I have to Genlock.

Sorry, I posted before I had finished my first cup of coffee of the day. Numptie of the day award goes to me I believe

[rosswill]

I'll add my support for the TV-One products. I own 2355A's and 7200's. I like the fact you get duel channel conversion in a 1U space and use them almost daily. Worth noting the 7200 only supports DVI up to 1280x1024/60 whereas the 2355A supports 1920x1200. in recent firmware the EDID has improved. The only downside for me is lack of DVI loop through for local monitoring, which forces me to include DVI distro in my setup. The plus side however, is that I can output simultaneous DVI, SDI/HDSDI, and CV from Catalyst with ease as well as up/down/cross converting other broadcast feeds to switch to my output device. I think from memory there are 11 inputs on the 7200 and 5 on the 2355A.

Regards

Ross