1080p over VGA
Hello Izzie friends!
I am running a very simple video playback session with 1080p Pro Res files on a Mac running El Capitan and Isadora 2.5.2. I usually run to a native 1920x1080 projector over HDMI with predictable full HD 1920x1080 output from Isadora.
Now I am faced with touring a show where the theatre house projectors, although native 1920x1080, are running VGA cable due to long cable running distances.
My limited understanding is that I can run my 1080p files over VGA to about 50’-75’ with good results. However when I go out via VGA, the output resolution from Isadora is knocked down to 1280x1014 or 1024x768 and 4:3 aspect ratio, no matter the cable running length or other tested variables.
Is there a solution - can I run 1080p files over VGA?
You can do 1080 but there are some variables that you always have to deal with, and often, over long distances you'll get signal degradation.
. First issue your dealing with is EDID loss, which is monitor info that is being sent back from the Montour to the computer over the signal cable. If the cable is too long or the computer output is does not have a robust VGA port (meaning good RAMDAC and or voltage regulator ) Windows will default to xga resolution or similar.
For your setup try to
-use the built in DVI-I or VGA port if you have them. The built in ramdac is more capable to drive higher resolutions even more than 1080. (This is how you can drive a 3h2go at 1280x1024x3 or 2h2go at 3840x1080 over VGA. You'll notice that if you go through an DP or HDMI adapter your resolutions will be much limited and your signal prone to more interference.
-use a VGA amplifier/booster. It essentially rectifies the voltage and stabilizes the signal. The placement can vary, from near the source to near the output.
-get an EDID emulator. This will act as a display that you set at your intended resolution. It will pass through the signal regardless of what you connect further down the line.
At any rate, analog signal is becoming obsolete, and most places are now running SDI or fibre. Try to spec that in your rider, or provide your own 300ft SDI cable. Get a inexpensive HDMI to SDI as well and that's the best setup currently available.
mark_m last edited by mark_m
Laurel, in addition to what @LPmode has suggested I would suggest running your own cable. This is what I do when faced with this situation.
I go all precious artist and tell the theatre techs that analogue transmission via VGA is unacceptable in this day and age, and we need to stay in the digital realm. If the theatre house projectors are native 1080 then they will have an HDMI or at worst DVI input.
I have several HDMI over Cat5/6 extenders, some by Kramer, some by Extron, all of which can be picked up dirt cheap on eBay. They connect together with a *particular* shielded twisted pair ethernet cable. Once you get the cable right, they just work, up to 60m or so, and only need power at one end. Importantly, they transmit the EDID information, which some cheaper HDMI extenders do not.
So I bring my kit along and insist that the theatre techs run the cable from my control position to the projector, and attach the Kramer / Extron box at the projector end and hook that up to the HDMI / DVI port of the projector. I also provide the short link cable.
Example Kramer extender: PT-571/572+
Example Extron extender:DTP HDMI 4K 230 TX/RX
And then shielded twisted pair cable such as this which is what I use.
As I said, I bought all my extenders cheap off eBay or at auction.
ALSO I've been encountering more and more projectors which have an ethernet port which receives Video over Cat5 cable. Just in the middle of a job where we're using four Panasonic projectors equipped with what they call Digital Link connected via STP ethernet cable to four of the Kramer transmitters. Works a charm.
Mark (no, not that Mark!)
CitizenJoe last edited by
@mark_m, what are you using as the interface between the computer and the panasonic digital link? For example, do either of the extenders that you've listed above work, or do you have to use the Panasonic version?
mark_m last edited by
Hugh, we're using these TP-580T Kramer transmitters:
We have two ATI cards on the computer, each with four Display-port out. So we have DP-> HDMI patch cables into the TP-580Ts, then STP Ethernet cable straight into the Digital Link input of the projectors, which are Panasonic PT-EZ770ZL. The projectors are OK (best cost-effective short throw the budget could stretch to) aside from the fact that they're white.
Other projector companies seem to be adding this connectivity in: DigitalProjection for a start. HDbaseT seems to be another term for what Panasonic call Digital Link.
The fact that the Kramer extender works makes me think that the Extron one would as well, but I've not tried it. Might give it a go.... Anyhow, the Digital Link works great, and saves having the Receiver and an additional patch cable up in the roof with the projector.
CitizenJoe last edited by
@mark_m - thank you.
I have two of the PT-DW830's with Digital Link, but I've never even thought about trying it! I've been using VGA, simply because I own so much of it - thousands of feet. I'll look into it. I wonder if it would work with a TH2G?
For future reference, I've found a page listing compatible equipment: https://panasonic.net/cns/prod...