OT: HDMI vs. HD-SDI

Jay Gladwell wrote on 10/29/2008, 7:37 AM

Still trying to make certain I invest in the proper production monitor, so I've done some basic research on the differences between HDMI and HD-SDI.

In a nutshell:

HDMI - "the previous maximum pixel clock rate of HDMI interface was 165 MHz which was sufficient for supporting 1080p at 60 Hz and WUXGA (1920x1200) at 60 Hz."

HD-SDI (SMPTE 292M) - operating at 1.485 Gbit/s and 1.485/1.001 Gbit/s supports 720p,
1080i.

Therefore, if I'm understanding this correctly (and I may not be), it appears that HDMI is the better choice for viewing/grading video at 1080p in full resolution. Is that an accurate presumption?


Comments

rmack350 wrote on 10/29/2008, 8:57 AM
I think if your only concern is whether you can output 1080p then a current rev of HDMI would do the trick.

HD SDI gets you into a professional technology level that might be better for grading and so I'd be looking at monitors that at least have the possibility of HD SDI, even if you don't plan on using it. For example, we just ordered a 52" panasonic plasma monitor that accepts modules for things like HD-SDI. (I wasn't involved in the purchase, this thing isn't for grading but it's still going to accept output from a Kona card and it'll get some use with SF film festival committees, otherwise it's just a home TV.)

Rob
Bill Ravens wrote on 10/29/2008, 9:32 AM
Jay...

Can you go somewhere to look at a production monitor with HD-SDI. Once you've seen the difference, you'll be sold. Unfortunately, a production HD monitor is pretty expensive. Part of the reason for the cost is because production monitors are very carefully controlled to meet very stringent standards. HDMI is a consumer version of HD-SDI. So, while HDMI is digital, it's, quite simply, not the professional level of HD-SDI. In the film school I attended over the summer, it is not uncommon for an edit bay to have at least two HD-SDI monitors, with color timing set to the "average" of the two. I should add that the NLE of choice, in school, was an Avid mojo system. No one would dream of going to film with something like Vegas. The very ultimate setup is a monitor with built in waveform display. Now, were really talking bucks.

Having said that, if your customer base is viewing on HDTV, I would question whether a production monitor is worth the expense. If your intent is to go to film, don't scrimp, get that production studio monitor.
Jay Gladwell wrote on 10/29/2008, 10:04 AM

Rob, thanks for your input!

Bill, I have no 'grand delusion' of going to film, I'm just wanting to make certain I'm outputting a decent, consistent image.

Frankly, at this level, I can't afford not scrimping. My clientele thus far cannot support it financially. I'm certainly not getting rich doing this!


Grazie wrote on 10/29/2008, 10:19 AM
I'm certainly not getting rich doing this!

Ah, but your soul is?

And what was it? "Enjoy yourself in the art . .and not . ." how does it go Jay??

Grazie
Grazie wrote on 10/29/2008, 10:21 AM
Bill, great explanation, thank you - I even understood what you said. Esp liked the 2 monitors being set to the average!

Grazie
rmack350 wrote on 10/29/2008, 12:55 PM
Bill said more forcefully what I was thinking. The big question isn't HDMI or HD-SDI, it's how good the monitor is. For the most part, a monitor with at least the possibility of HD-SDI is more likely to be in the ballpark you want to play in, even if you don't buy the HD-SDI option. Still, it's an expensive playing field.

The thing with HD-SDI is that it fit in with pro gear like a Xena card, Decks and cameras with SDI, waveform monitors with SDI, etc,etc. And SDI cable runs can be very long, if you need that.

Rob
farss wrote on 10/29/2008, 2:10 PM
I'll second what Rob is saying. The SDI interface is as flexible as composite video. You can run it a long way and daisy chain it. Actually being digital it's more flexible than composite video, you don't have to worry about signal degradation.
For Jay who has an EX3 I'd think having a HD SDI monitor would be a bit of a no brainer. SIngle coax from the camera is all you need to hook up a monitor. We recenlty bought the 9" TV Logic and a couple of Panasonic 17" for this purpose. All of these monitors can be run from battery, have pixel to pixel mode, waveform and vectorscope displays etc. The 9" costs almost as much as the 17". All this kit does get expensive. Then again if you own an EX3 you're obviously thinking to buy a nice W.A. zoom. At the cost of one of those you might get the dealer to throw in a monitor for free.

Bob.
ushere wrote on 10/29/2008, 3:30 PM
i love these discussions....

don't get me wrong, i'm all for monitoring at the best possible level - but having just visited a few people who've recently acquired lcd / plasma tv's, i have to say that i feel all my cc tweaking and attention to scopes, etc., is wasted. nearly every one of them had either the colour way up, and the contrast set to hard, or everything was somehow soft.

as for 'theatre look', lets not go there!

leslie
John_Cline wrote on 10/29/2008, 4:07 PM
I've always operated by making sure my monitors are calibrated and what I'm doing looks good to me compared to the commercial and broadcast material that I watch on the same monitor. It's all a matter of referencing a wide variety of sources and aiming for the happy medium.

Since I can't go to each persons house and calibrate their televisions, what happens after it leaves here is completely out of my hands and I don't worry about it. If their TVs are too saturated, for example, my stuff won't look any better or worse than everything else they watch.

There was one long departed individual here on the forums that insisted on compensating for the lowest common denominator by making his stuff look "good" on a cheap Walmart TV, which probably made it look like crap on a TV that was owned by someone that took the time to calibrate it. At the very least, his stuff looked different than what they were used to seeing.

As far as HDMI vs SDI, BlackMagic Design has a reasonably priced HD/SD SDI to HDMI or DVI converter that works really well.

http://www.blackmagic-design.com/products/hdlink/
GlennChan wrote on 10/29/2008, 4:25 PM
Can you go somewhere to look at a production monitor with HD-SDI. Once you've seen the difference, you'll be sold.

I've seen a wide range of production monitors... HD-SDI doesn't really make a big difference to image quality. Even at NAB, some of the manufacturers don't show the greatest material on their displays (e.g. visible compression artifacts). It mostly comes down to the quality of the display, and the display not doing consumer image enhancement tricks.
Though then again, some "professional" broadcast HD monitors aren't that great.

2- From a quality control point of view, you want to monitor your deliverable. If you are making Blurays, then get a monitor with HDMI and double check your final disc. There's no point in going HD-SDI in that situation.

If you are making broadcast masters and deal with VTRs, then you really really should get a (HD-)SDI monitor so you can monitor the SDI output off the VTR and watch the confidence heads. The monitor should also handle deinterlacing, which the Decklink I believe won't do (24p masters generally are delivered as 60i). But this gets into some esoteric stuff.

3- IMO, you'd be doing a professional job if you can encode blurays + HD-DVDs with less compression artifacts. I was at the JVC booth at NAB and they were showing Planet Earth (sorry: don't know if it was bluray or HD-DVD)... you could obviously see compression artifacts in the source.

- If the monitor is really expensive, then there isn't much point in getting built-in scopes. You can get the scopes separately and on another display.

it is not uncommon for an edit bay to have at least two HD-SDI monitors, with color timing set to the "average" of the two
From my experiences, this is not a common practice.
Jay Gladwell wrote on 10/29/2008, 7:56 PM
Thanks to everyone for their input!

I know what I would need in a perfect world, but here in Miami, things ain't perfect.

It's not a matter of it being a no-brainer, it boils down to be a no-monier.

And yes, Grazie, I love what I'm doing and having a ball every step of the way. In fact, I just got back from shooting test footage in the Everglades--the weather *was* perfect.

"Love the art in yourself, not yourself in the art." -- K. Stanislavsky