Film-Tech Forum ARCHIVE: HDSDI Inputs

This is topic HDSDI Inputs in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Harold Hallikainen (Member # 5405) on 01-04-2017, 03:56 PM:

Many internal servers include a dual HD-SDI input. Is anyone using these? What for?

Thanks!

Harold

Posted by Steve Guttag (Member # 268) on 01-04-2017, 04:26 PM:

HDCAM/HDCAM-SR come to mind but in general terms, anytime broadcast or civilized video is to be connected. My guess, just like the LTC outputs, 99.9% of the people pay no attention to them.

Posted by Jim Cassedy (Member # 4115) on 01-04-2017, 04:51 PM:

One of the venues I work at uses the HD-SDI inputs for HD-CAM, as Steve says.
That particular location does a lot of Asian-themed screenings and festival
work, and we still seem to get a lot of HDCAM content from Japan, so we've
got a macro on the projector for it and use it fairly often.

Same place also has a mac-pro occasionally used for playback of Pro-Res
and other computer format files, and they've actually got a card in that
computer that outputs SDI, so we've got an SDI switcher to route either
the computer output or the HDCAM deck into the SDI input on the projector.

Posted by Harold Hallikainen (Member # 5405) on 01-04-2017, 07:22 PM:

I'm not familiar with HD-CAM. Can HDMI serve that purpose?

Harold

Posted by Leo Enticknap (Member # 534) on 01-04-2017, 08:15 PM:

All the broadcast standard HDCAM and HDCAM SR VTRs I've used have HD-SDI as the only digital video output. If you need to hook one up to an HDMI input (e.g. on a cat745), you'd need to go through either a scaler or an SDI to HDMI converter box.

We use the dual-link HD-SDI inputs on our Barco Alchemy to take the input from an Aja FS-2 scaler, to which all our alternative content sources are connected.

Posted by Scott Norwood (Member # 30) on 01-04-2017, 09:34 PM:

Pretty much every "film" festival needs the HD-SDI input. As others have said, it gets used by videotape decks, computers, hard-disk and/or solid-state playback devices (AJA Ki-Pro, Sound Devices Pix series), and digital signage players.

The nice thing about HD-SDI is that, unlike DVI/HDMI, it can be run for great distances without worry (especially important if the projector is not located in the booth) using relatively inexpensive cables and is very reliable.

Since Steve mentioned it: what is the LTC output? Linear timecode? Something else? I have never seen it used, although I could see timecode being useful for automation purposes.

Posted by Carsten Kurz (Member # 5396) on 01-05-2017, 08:35 AM:

SMPTE LTC, for various purposes. Some servers have it per default, some as an option. As Steve says, it is not used very often. Aside from these server supplied LTC sources, there is also a new standard for Sync-Tracks on the DCP audio channels, Harold knows about it.

ATMOS and d-box so far use proprietary sync formats on some DCP channels. Some of them suffer from the watermarking that usually had to be active on all audio channels. That is solved now by the use of special KDMs that allow to disable watermarking for specific channels, leaving their digital TC data untouched.

The trouble with the IMB and IMS systems is, for good reasons, they leave out the expensive option for an HD-SDI input with Enigma based decryption. But having HDMI is not enough (although HD-SDI->HDMI converters can deal with some applications). Some IMB systems also use(d) combined HD-SDI output/input for stacking applications.

- Carsten

Posted by Kristo Nalo (Member # 9748) on 01-05-2017, 11:36 PM:

I encounter the same situations too. My friends help me to fixed it and until now I never encounter that again.