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SDI input to video projectors


Sydney

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I'm picking up an issue that's been discussed but perhaps not resolved in other posts.

 

A lot of new DLP installation projectors come with HD/3G SDI input as standard.

This has a number of desirable benefits over data cabling for multi-screen video projection, particularly the simplicity and cost benefit of running long single, coaxial cables to each projector.

 

Personally I've found the combination of Displayport to DVI active adaptors to long DVI leads, probably with EDID Emulators as well as DVI extender/boosters to be very expensive, cumbersome, hard work to install and far from reliable.

 

My question therefore - For Watchout users is there a tried and tested solution to convert from say an AMD W7100 card with DP outputs to SDI?

Is SDI and baseband video transmission a fundamental problem for Watchout which needs a data connection to the display?

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The issue is a hardware issue.

Seems no one offers a graphics card with both hardware accelerated DirectX 3D rendering AND SDI output.

Hence the need to convert.

AMD has made some noise that they may may make a version with SDI output

but have not seen anything yet.

 

It is not really correct to indicate that "... Watchout which needs a data connection to the display"

It needs a connection supported by the graphics card of course, but that certainly can be YUV video formats via DVI or HDMI.

Granted RGB output used by most computer displays has its advantages, but that is not the only choice.

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Hi there, i fail to agree with the recurring remark that sending dvi over a long distance and using emulators is an expensive choice and / or it's hard to install and irreliable? Compared to the projectors or a proper multi screen processor these costs are peanuts which leaves me wondering what type of market you and other pro-sdi techies are in? I have never experienced issues with fiber connections or at least no more than copper connections.

Most important reason for not wanting to use sdi, apart from the fact a computer doesn't natively support it (which isn't really an issue in most productions as watchout is fed into a background layer somewhere) is the fact it only supports smpte resolutions. Going for a wuxga native for instance would be impossible.

Just my two cents.

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As Jim says, it's a hardware issue.  You need a good converter box, and most of those are HDMI to SDI.  I have found active mini-DP to HDMI converters (Star Tech makes them for one).  But the good converters are expensive - the cheaper boxes don't do a good conversion to 3G, only HDSDI.  So there goes your "cheaper" solution.  I agree that 3G cable is easier to string since fiber is more fragile, but I'm not sure there is much in the way of cost savings.

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Based on many years experience of multi-screen video installation from standard definition up to the present day, a coaxial cable always works, a data cable installation works beautifully on some shows and never works properly on others. Nobody want this kind of headache. It may well be that SDI isn't the best option for Watchout based shows for the reasons mentioned above. I'm just posing the question for those who would like to use SDI.

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The guys/girls over at hippotizer have recently released a product called: Linx dpxsdi

 

it looks pretty promising and we are waiting for a sample so we can try it out at our warehouse with various media servers, watchout included. 

 

if anyone else have tried it out, please let me/us know of any pros/cons.

 

Will of course give feedback when tried and tested. 

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The guys/girls over at hippotizer have recently released a product called: Linx dpxsdi

 

it looks pretty promising and we are waiting for a sample so we can try it out at our warehouse with various media servers, watchout included. 

 

if anyone else have tried it out, please let me/us know of any pros/cons.

 

Will of course give feedback when tried and tested. 

 

Virtual displays make such an approach (one output externally split to four outputs)

available without any of the loss of function that would have occurred pre version 6.  ;)

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JFK, I was looking at that very scenario this week, however, don't you loose blending and geometry corrections when using virtual displays?   FYI, Aja has a similar box that is 4KHDMI to 4x HD-SDI at a much more reasonable price than the Hippo... I'm looking into testing with that unit.

 

--D

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I like DataVideos DAC-70, which can take an HDMI input, and spit out SDI and HDMI at the same rate/resolution.

 

I like this, as the graphics card sees a static handshake, while the SDI can be 100 m / 333 ft without loss, and you can connect/disconnect as much as you need to without resetting the graphics card and screwing up the settings.

 

Also, I can put a local HDMI monitor on each output, or with a switch, to see each output, even if my operator position doesn't allow for a view of the screens.

 

Actually, I usually use an E2, with WO going into the background layer, as Walter mentioned earlier.

About Walter: I have been in this industry for 30 years, and have found SDI to be much more reliable and simpler to distribute, then any DVI solution. Fiber/copper, doesn't matter. Between the handshaking, short distances, (I know fiber wins on distance,) and expensive connections & cables, I'll go SDI anyday.

 

Just my 2 cents...

 

Kevin Lawson

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Bluetonesblue said:

"I like DataVideo's DAC-70 which can take an HDMI input, and spit out SDI and HDMI at the same rate/resolution.

 

I like this, as the graphics card sees a static handshake, while the SDI can be 100 m / 333 ft without loss, and you can connect/disconnect as much as you need to without resetting the graphics card and screwing up the settings."

 

The Decimator MX-HD Cross converter is similar. Seems to have an 'EDID Manager" built-in. Disconnect the output end, and Windows does not even blink an eye. Decimator is also about half the price of the DAC-70.

 

A friend/Watchout user recently did a latency test between the DAC-70 and the Decimator. If I recall right, the DAC-70 had 2 frames of delay from original, and the Decimator 3 frames.

 

Thomas Leong

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The Decimator MX-HD Cross converter is similar. Seems to have an 'EDID Manager" built-in. Disconnect the output end, and Windows does not even blink an eye. Decimator is also about half the price of the DAC-70.

 

A friend/Watchout user recently did a latency test between the DAC-70 and the Decimator. If I recall right, the DAC-70 had 2 frames of delay from original, and the Decimator 3 frames.

 

Thomas Leong

 

The Decimator can also be used as a 1 to 4 distribution amplifier by the way.

 

Thomas - How did you or your friend connect the Watchout display PC to the Decimator?

Did you use an active DP to HDMI adapter?

 

In terms of latency, I wonder if this might cause an issue if more than one converter was used on a graphics card.

For example on a two screen edge blended projection you might put converters on Display Port output 1 and 2.

If the latency was slightly different on each converter the blend could be visually out of sync.

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I have a showSage built four output watch tower that uses display port to hdmi natively out of the card and then use Black magic hdmi to sdi boxes per out put

Works like a charm

The only thing I don't like is hdmi connectors don't lock. But the install is all rack mounted so less chance of movement.

Ben

 

Have you tried edge blending two or more outputs from this system?

Just wondering if there's any visual sync issue using multiple converters?

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The Decimator can also be used as a 1 to 4 distribution amplifier by the way.

 

Thomas - How did you or your friend connect the Watchout display PC to the Decimator?

Did you use an active DP to HDMI adapter?

 

In terms of latency, I wonder if this might cause an issue if more than one converter was used on a graphics card.

For example on a two screen edge blended projection you might put converters on Display Port output 1 and 2.

If the latency was slightly different on each converter the blend could be visually out of sync.

 

Sydney, for the latency test, my friend connected the Decimator direct to his laptop's HDMI output. Likewise with the DAC-70. Watchout was not involved.

 

If used in a blend setting, using different branded converters may introduce more problems than necessary. So we have not tried a blend scenario yet - don't have enough Decimators...yet. Looking into getting more.

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We have done a couple systems with DAC-70's in line. They do have an EDID manager, of a sorts, built-it as well.

 

I have done blended with them, and no issues. I also was not combining multiple different converters, but all the same, so I had no issues with tearing, sync, or anything.

 

One of these was a 4 output blend, with a backup system online. I could switch the DAC-70's in and out of the matrix switcher to the PJs with no breakup or loss of sync across all outputs.

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