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Analog to digital video conversion thread... - Printable Version

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Analog to digital video conversion thread... - Dylanear - 06-12-2019

I'm wondering if we can make a list of all the devices we've tried to convert video output to modern digital (HDMI/DVI/DisplayPort) signals. Which support Sync On Green/SOG and which have failed. 

I need to buy two. Ideally one would support SOG and 2048x1556 res. But if I'm not being picky one that supported SOG and 1920x1080 (For SGIs) and another that supported 2048x1556 (for my Altix blade servers) would work. I'd just like to find one video A/D to rule them all. 

There's SO many out there, and some support SOG, but I've never seen that listed in the specs, pretty much ever.

RE: Analog to digital video conversion thread... - vishnu - 06-14-2019

By video output do you mean like from VHS? Because NTSC VHS is roughly equivalent to 333×480 pixels and that's going to look really rinsed out if you try to expand it to 2048x1556. Maybe I'm missing the point...?

RE: Analog to digital video conversion thread... - Dylanear - 06-16-2019

(06-14-2019, 04:07 AM)vishnu Wrote:  By video output do you mean like from VHS? Because NTSC VHS is roughly equivalent to 333×480 pixels and that's going to look really rinsed out if you try to expand it to 2048x1556. Maybe I'm missing the point...?

I'm referring to the main video output from any given SGI which is typically 1280x1024 using Sync on Green. As in a VGA to DVI/HDMI/DisplayPort adapter I can plug into a 13W3 to VGA adapter plugged into an SGI.

Surely I'm not the only one on here who wants to run an SGI on a modern LCD monitor with no analog inputs? Smile

RE: Analog to digital video conversion thread... - Raion - 06-16-2019

You cannot run a SGI on a modern display unless it supports DVI-I. That's my experience. Most "converters" on the market cannot understand SOG signals.

RE: Analog to digital video conversion thread... - Dylanear - 06-18-2019

(06-16-2019, 03:15 AM)Raion Wrote:  You cannot run a SGI on a modern display unless it supports DVI-I. That's my experience. Most "converters" on the market cannot understand SOG signals.

Finding adapters/converters that do support sync on green and listing one's we've tried and know don't support sync on green is the precise purpose of this thread. 

I've got one cheap generic adapter I really doubt will use sync on green and a Tripp Lite converter on order that I hoping might. 

Worst comes to worst my understanding is there are sync on green to standard descrete sync signal converters.

RE: Analog to digital video conversion thread... - Raion - 06-18-2019

We may need to look into making our own. I would be down for that as I prefer modern panels tbh

RE: Analog to digital video conversion thread... - Dylanear - 06-18-2019

(06-18-2019, 06:56 PM)Raion Wrote:  We may need to look into making our own. I would be down for that as I prefer modern panels tbh

A nice, elegant little 13w3 to HMDI or DVI-D adapter would be pretty nice. But may be pretty involved. I'll buy one if someone makes a nice one at a reasonable price!

Here's a SOG to discrete sync converter. Not super expensive and at least it's small. 

https://si87.com/epages/3738123e-8b74-40b2-bd96-ddff0f19d352.sf/en_US/?ObjectPath=/Shops/3738123e-8b74-40b2-bd96-ddff0f19d352/Products/7053

RE: Analog to digital video conversion thread... - Jacques - 06-18-2019

(06-18-2019, 07:19 PM)Dylanear Wrote:  
(06-18-2019, 06:56 PM)Raion Wrote:  We may need to look into making our own. I would be down for that as I prefer modern panels tbh

A nice, elegant little 13w3 to HMDI or DVI-D adapter would be pretty nice. But may be pretty involved. I'll buy one if someone makes a nice one at a reasonable price!

Here's a SOG to discrete sync converter. Not super expensive and at least it's small. 

https://si87.com/epages/3738123e-8b74-40b2-bd96-ddff0f19d352.sf/en_US/?ObjectPath=/Shops/3738123e-8b74-40b2-bd96-ddff0f19d352/Products/7053

Anybody ever tried building the Instructables PS2 Sync on Green converter ? It seems like something like this should work...Still outputs to VGA though.

RE: Analog to digital video conversion thread... - jan-jaap - 06-18-2019

I've tried a few things myself.

First of all, if you want to get rid of SOG, look for an Extron 112xi distribution amplifier. It's been around for a long time and you can find them cheap.

I tried a small VGA-to-DVI converter with my Onyx2. It didn't deal with SOG. Fortunately, it isn't hard to program the Onyx2 to put out separate sync rather than SOG. What proved to be impossible in the end was to get a stable, clear picture. That's because monitors usually have buttons to either manually or automatically do the 'fine' adjust of sync. This adapter didn't have that. My attempts to adjust the refresh rate of the display output of the Onyx2 and get a sharp picture were not successful.

I have since bought a pair of Gefen VGA-to-DVI scalers. They have the adjustment buttons and many more options than the first adapter. They should be good up to 1920x1200.

I just haven't tried them out yet...

RE: Analog to digital video conversion thread... - Dylanear - 06-19-2019

Let us know how those Gefen scalers work!

I've tried a $15 one off Amazon on the VGA output of my Altix XE servers and that works ok to about 1600x900, but goes nuts when using a low rez signal, like a basic text console under linux. To be fair, it says it's resolution range is 800x600 to 1920x1080, but I've never gotten it working at 1920x1080. Really doubt it'd understand SOG.
This one. I can't recommend it, but at least it's not much money wasted.
https://www.amazon.ca/gp/product/B07C82R8PB/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1


I should have this to try later in the week and it supposedly does up 1920x1440. Says it scales up "VGA" to 720p, so we'll see how it handles low res linux displays.
https://www.tripplite.com/vga-with-audio-to-hdmi-converter-scaler~P116000HDSC1

Sadly I have no working SGI near me at the moment for SOG testing, but hopefully that'll change before long.