Tech Pack
Geoff Notes
Spinning off a separate chain to not muddy the waters of the main. I thinned out the copy list a little; please add folks back if I accidentally removed someone who needs vis here.
Attached is our tech pack. This doesn’t reflect the expansion of columns we just did, but everything here still applies to the conversation. I won’t be able to get all the paperwork updated before you’re on the volume and wanted to make sure you had some talking points.
Michael and Emily can speak to processor/render node layout and talk through the expansion we just did.
Some general notes on the system:
Some stages use a video switcher between their render nodes and LED processors. We do not, for two main reasons. Video switchers can introduce additional frames of latency Many video switchers don’t accept custom resolutions, and all of our slices are custom Custom resolutions - these were picked to maximize LED processor/render capability. If we’d used standard resolutions we would have had to (approximately) double our render nodes and processors. (See also: twice as expensive for processing and rendering).
We can also use custom mapping to pick up tiles that would normally not fit in a raster. Emily can show you our one ceiling column that has a different mapping, so the shape works but the mapping is a bit stange.
There are two main cabling considerations for the LED tiles - power and data Power - columns on the main wall are cabled so one column (13 tiles) is one circuit. If we need to power cycle, we only lose one column at a time. Data - Data is cabled in columns of 6 or 7 tiles depending on where in the system they are. Cabling this way allows data throughput of up to 30 fps with frame doubling, or up to 60 FPS without, assuming 12bpc The LED tiles have 1Gbps NIC on their receiver cards; real world throughout is estimated at 756Mb.
Refresh rate correlates to shooting frame rate. Ex, 24 FPS would use wall refresh rate of 24 hz. 48 Hz with frame doubling. (24 fps content being refreshed twice). 30 fps would use a refresh rate of 30 Hz, or 60 with frame doubling.
Our tiles have a 2.3mm pitch; 216px wide by 216px high in a 500mm x 500mm cabinet. 46,656px per cabinet.
LED processor (SX40) to switch (Xd) is 10Gb fiber. XD to LED tiles is 1Gb Cat6a.
Bandwidth formula (bits) is: Bit Depth (bpc) * Refreh (Hz) * X (diodes per pixel) * px per tile * tiles
12 bpc * 60 Hz * 3 (RGB) * 46656 * 7 = 705,438,720 bits = approx 705Mb
In this example 8 tiles = approx 806 Mb, too much for the receiver cards, so we default back to 7 as our max tiles in a data chain.
Hope that helps! Please let me know if I can clarify anything.
Best,