HD-SDI, what is it for?

[Alexander Alexandrov]

i'm moving up to red one and future models from DSLR video world (d90, 5dII).
I'm used to shooting with using a small field monitor with HDMI feed and doing some color correction in post.

overall, moving up from amateur to pro.

can anyone explain what are the ways to use HD-SDI and needs/benefits of it?

I'm planning to record to CF cards or Red drive in the field and using a RED 5+inch LCD.

what is the talk about HD-SDI, what is it for, and how does the workflow of it work?

i vaguely think it is used for real time proper monitoring in the field? (but cant this be done with an HDMI output / monitor as well)? and perhaps used for capturing and better color correcting?

if someone could clarify this topic for me or put me in the proper direction to learn more, i'd appreciate it. this part of the workflow process in unknown to me.

thank u.

 

[ericyoung]

If you google HDMI and HD-SDI I'm sure you'll find out far more technical information than you ever wanted to know!

From a practical point of view both HDMI and HD-SDI allow for high definition monitoring from the Red.

The first is a consumer standard and the second a professional one. Professional monitors by and large have more stable, colour calibratable, colour standard pictures with any number of professionally useful features like waveform displays, but do not have HDMI inputs. Consumer TVs and monitors don't have HD-SDI but are readily available at many locations and are a lot cheaper.

HD-SDI has much more robust and reliable locking BNC type connectors and is the standard in all high definition installations. HDMI is useful for connecting to readily available and cheaper consumer displays. HDMI may exhibit more lag as consumer TVs often have signal processing to allegedly improve picture quality.

Theoretically you could capture either signal for editing, but would negate the point of shooting with a $17500+ camera recording 4K raw data!

 

[Alexander Alexandrov]

thank you! that's what i needed, without getting into too much tech details.
with me not interested in capturing anywhere but onto the red, the major benefit of hd-sdi is proper monitoring.

how does red LCD compare in its motoring capabilities to HD-SDI screens.

 

[ericyoung]

Long HD-SDI cables and connectors are also significantly cheaper than long HDMI cables. The main reason why consumer kit doesn't use it is that it doesn't allow for HDCP copy protection.

I wouldn't worry too much about whether to use HD-SDI or HMDI screens on set for monitoring unless you are shooting feature films with the budget for a video village. Chances are the displays you can afford when you're starting out will not be top end colour calibrated ones anyway. The more important factor is whether the monitor can display the full resolution of the HD-SDI or HDMI output (or zoom for 1:1 pixels) so that you can use it for focus, and also whether it will display the camera status displays and menus. Various displays and whether they work with Red have been discussed on this forum. Use the Google search option in the drop down forum search menu.

[ EDIT: Rereading my post I realise I left out a couple of very important points. One - The HD-SDI outputs don't show all the menus and status displays as HD-SDI is 720p output and so only shows the centre 720lines of the picture. Ie the menus, status displays and so on are partially or completely cropped off and so can't be viewed on HD-SDI monitors! To see the menus and status displays you must either use RED LCDs or EVFs, or use HDMI (or DVI with adaptor) monitors. Second - not all HDMI monitors will display the full 848 lines required to see the menus and status displays whether by native resolution or scaling the image. Build 18 camera firmware apparently fixes some of the HDMI incompatibilities but only testing your actual intended monitor guarantees it will work. Some models have already been tested with Build 17 and discussed before in these links:
http://www.reduser.net/forum/showthread.php?t=22689
http://www.red.com/faq/will-any-hdmi-monitor-or-tv-work-for-monitoring-output/
http://www.reduser.net/forum/showthread.php?t=28816
but not all have been retested with Build 18.]

The Red Pro LCD 7" is pretty high resolution by small LCD standards and is much better then the Red LCD 5.6" in terms of viewing angle, brightness and resolution. It can be successfully used as your only monitoring and although not as high resolution as the EVF it is possible to focus off it. It also has one User Assignable button which can be used for controlling a selectable camera function.

Still if you have a bigger full HD resolution HD-SDI/HDMI onset monitor, it will certainly be useful. And an HDMI one will ideally also display the menus and status information,

One caveat, even with a top end monitor it's important to remember it's not truly WYSIWYG when used with the Red as it is not displaying the full information in the R3D file, so it can only be a limited guide as far as colour and exposure goes.

 

[Alexander Alexandrov]

thank you sincerely for the update.
i'm getting a used red one kit and it comes with 5+ inc red lcd. i also have a manhattan lcd HDMI monitor; so i will test both, but for efficiency i prefer to just stick with the smaller red lcd if it works out for focusing
if not, will perhaps look more into smallhd.com

 

[ericyoung]

The smaller 5.6" Red LCD will work fine, but it has a very tight viewing angle. Fine for a single operator, but not great for anyone to the side. Good luck!

 

[ericyoung]

Seems from this thread:
http://reduser.net/forum/showthread.php?t=29954

that the current Manhattan model won't show the menus and status displays, whereas the SmallHD thread implies theirs will.

 

[Alexander Alexandrov]

yep, looks like it.
i have a MLCD A model, will see how it performs, perhaps will update it to their C model if possible or sell it.

 

[Alexander Alexandrov]

what is the difference between single channel and dual channel HD-SDI?

 

[MichaelP]

Dual Link is usually used to carry HD RGB as 4:4:4 or can use used to carry left and right eyes in 4:2:2 stereo 3D capture and playback.

Michael