Welcome to our community

Be a part of something great, join today!

Log in
  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Live Grading on Dragon

J

Jesse Korosi

Well-known member
Joined
Jul 30, 2009
Messages
172
Reaction score
0
Points
0
Location
Los Angeles, CA
Website
www.jessekorosi.com
Hello all,

I am curious whether or not anyone has done live grading with the Dragon.

As it has been a little while since I have last ran a proper test checking the SDI signal out the back of a RED camera, I am curious if this now matches the actual recorded file. Therefore allowing users to live grade with Truelight, LiveGrade, or even using a Pluto box or something of the like...

I am hoping to have my hands on a camera within a week or two to test this myself, but figured it would be nice to hear if anyone has actually done this already in the field.

The first thing that I would love to hear if anyone has done would be to:
http://www.mediafire.com/view/yj8j3m5ya14a678/Testing_ColorFlow_From_Camera.jpeg

Thanks!
Jesse
 
A wide variety of workflows that coordinate the SDI feed with the RAW R3Ds can be created. The real question, at least at the moment, is just how many steps it would require.

You ask a key question about the fidelity of the SDI feed to the recorded file with the Dragon hardware. A new Dragon FW build is imminent, once we have that, then a proper round of testing is the only way to determine if your plan is viable. The issue has always been that in order to avoid problematic latency, the in camera decode was compromised a bit. With the ever increasing compute power on board, and a few years to refine things, perhaps the variation between the SDI "quick and dirty" decode and a full off-board decode has been narrowed sufficiently to support your intended pipeline.

In theory you could create an offset LUT on either side to facilitate matching, but I wouldn't count on being able to eliminate all the variables. Another potential issue is that AFAIK, the live SDI taps are 8bpc, so in order to "match" you would have to knock the off board decode down to an 8bpc iteration, at which point the color precision might be insufficient to support your color management goals.

Cheers - #19
 
Copy that. So in short; no, it is not possible. Maybe it will be when the new firmware and SDK are out. But the bottom line is: No...

I will update this thread in case anyone is curious to hear where this goes after some further testing.

Thanks!
Jesse
 
From the beginning, the SDI output of the RED cameras has been a "video tap" rather than a full on recordable live output.

Best case, the SDI signal is close enough to allow for a live grading workflow that offers a rough look at how various choices would impact the image. You could generate settings/LUTs that might be a nice starting point for final color and be close enough to the DPs intent to support a dailies look for 8bpc media assets.

IF you are rec 709 end to end then I think a workable kludge is possible. If you need to support a P3 emulation scenario I would expect an uphill battle.

FWIW, the strategy I typically employ, is to shuttle RedMags back to the workstation for review. In many cases I am able to roll 30 seconds of the lit set (with talent or crew on marks if possible) and run that through a quick grade/review step before the first real take. I haven't tried it yet with the newest builds, but you should be able to take that a step further and generate an RMD in RCX-Pro then load that into the camera as a monitor look. Not exactly "live" grading, and no ASC CDL support AFAIK, but for some shows it works quite nicely.

Cheers - #19
 
In regards to the video tap note, understood and that is how I have understood it thus far as well.

Some DP's however need to work in live grading scenarios. Rolling a clip, ejecting the card, walking it over to your DIT, downloading the mag, calling the DP over, dialing in a look, saving the RMD ... and then asking the camera assistants to step aside while you load it back in to the camera....for every setup... is not something pretty much any of the DPs I have worked with (that request live grading) are going to wait on. If this is the way you end up going, in my opinion, you should just monitor redcolor/redgamma out of the camera and deal with color after the whole mag's been downloaded. However for the DPs that use their DIT as a live interactive tool, while they are setting up lights, judging exposure and pushing or pulling things a certain way depending on the grade... downloading isn't something they are into waiting on.

Cheers,
Jesse
 
Live Grading feature in Resolve 10 works pretty well. I once did a test with Epic MX to check recorded image as displayed in RCX vs SDI output from camera. Shot a clip of a static scene, walked it to workstation- SDI feed out of RCX (with Rocket) on A side of monitor and Live SDI out of Epic on B side. They were identical to the eye and on waveform. (This was NOT the case with the Red One!) Sure there may be some 8 bit vs 10 bit difference etc but for many applications it is totally workable.

I suggest Resolve 10 with live grading and programming a key on the camera to switch the gamma to Redlogfilm. Want to live grade? Press RLF button and do a grade in Resolve. You can save grades and later apply them (automatically based on timecode if you want) when you interpret the RAW files as Redlogfilm which is always a nice place to start grading... There are lots of varieties of this approach but it can be really effective....
 
YES you can live grade on Dragon. Several different ways. We are doing it right now on a pilot.

You can pretty much do anything with a 3D LUT.

And let me just say - I roll my eyes when DITs claim "RED's SDI's" output is "inferior" and then the next day on a different shoot you run the SDI signal from an Alexa through a BlackMgaic HDLink - which is one of the most flawed screaming pieces of shit hardware ever made.

RED does need to step up to plate and understand the needs of CDL and 3D LUT workflows - and I am confident the wheels are in motion.

Having FULL RANGE out would be nice :)

But anyway - anyone who tells you that you can't do it - tell 'em they should hire me :)
 
Blair S. Paulsen said:
The issue has always been that in order to avoid problematic latency, the in camera decode was compromised a bit. With the ever increasing compute power on board, and a few years to refine things, perhaps the variation between the SDI "quick and dirty" decode and a full off-board decode has been narrowed sufficiently to support your intended pipeline.
Click to expand...

For the record the Dragon (and Epic & Scarlet) do a full debayer to SDI live - so not sure what you are talking about. They only do a "quick and dirty" 1/2 debayer is on playback.

Blair S. Paulsen said:
In theory you could create an offset LUT on either side to facilitate matching, but I wouldn't count on being able to eliminate all the variables. Another potential issue is that AFAIK, the live SDI taps are 8bpc, so in order to "match" you would have to knock the off board decode down to an 8bpc iteration, at which point the color precision might be insufficient to support your color management goals.

Cheers - #19
Click to expand...
Not in "theory" - in reality - you CAN create a 3D LUT to facilitate matching or film emulation or pretty much whatever you wanna do. It's done every day. And if you wanna talk about 8 vs 10 bit color precision on an SDI stream - well ... then we go down a long, silly road of talking about the processing boards behind monitors, etc.

My iPad retina is 8 bits of LOVE. That said - I like more bits. More pixels. More red wine. More Scotch. More pizza. But's more bits isn't always the answer.

Color management is often like a good cook making food for the starving. Yes it's perfect. And yes they love it.

The question is ... do they even actually know what they are appreciating beyond the obvious "this is great"?

I should stop posting tonight - the scotch is kickin' in ....
 
This may not be what you are looking for, but I recently came across an interesting solution.

I took the SDI feed out of my Epic MX into the BMD Ultrastudio Mini Recorder on my Retina Mac Book Pro. Using foolcontrol software I connected to my Epic MX wirelessly via the new REDLink. I was able to preview the live image and control metadata settings. These metadata settings are then saved to the clip that is rolled after the adjustments are made. This allows you to grade the image via the red raw metada controls before the clip is rolled and have those settings saved in the R3D's as metadata. If you added a wireless HDMI or SDI transmitter such as a Parralynx Arrow you could have this "live grading" setup totally wireless. All the metada settings you change via foolcontrol will show up immediately on the live SDI feed that DP and Director/Clients are seeing.

http://foolcolor.net/
 
Danai Chutinaton said:
This may not be what you are looking for, but I recently came across an interesting solution.

I took the SDI feed out of my Epic MX into the BMD Ultrastudio Mini Recorder on my Retina Mac Book Pro. Using foolcontrol software I connected to my Epic MX wirelessly via the new REDLink. I was able to preview the live image and control metadata settings. These metadata settings are then saved to the clip that is rolled after the adjustments are made. This allows you to grade the image via the red raw metada controls before the clip is rolled and have those settings saved in the R3D's as metadata. If you added a wireless HDMI or SDI transmitter such as a Parralynx Arrow you could have this "live grading" setup totally wireless. All the metada settings you change via foolcontrol will show up immediately on the live SDI feed that DP and Director/Clients are seeing.

http://foolcolor.net/
Click to expand...

Beware the HDMI out on the Epic. I am fairly certain that the signal out of HDMI is more crushed than SDI. At least that has been what I have found through my testing. If anyone else has an HMDI/SDI monitor they can A/B with the HDMI and SDI signal to confirm I have always been curious if it is the case with all Epics.

Eric
 
I have used Pomfort livegrade in the following way to great success in conjunction with Davinci Resolve.

Set Dragon to Redlogfilm Gamma
feed SDI into Blackmagic HDLink Pro being driven by Pomfort Livegrade.

Export CDL LUT.

Load Lut into Davinci Resolve.

Apply LUT to Dragon Material

Generate Dailies.

Done.

Works great. Really great with Dragon.
 
I should add that the results I get doing this with dragon "feel" better than when I had done this previously with an MX. Is it because the tap quality is better? I think that's at least part of it.
 
Hey guys,
Appreciate all of the passionate responses. haha

In regards to foolcolor, I was just looking at this in my prep bay actually. I am curious to run some more tests with this...

I go back to a very very simple question. DOES THE VIDEO OUT MATCH THE RECORDED FILE. Whether you like the HD Link or not Mark, the video when looking at it on a scope through this device vs the master file recorded in ARRI RAW...still matches. So if the Dragons recorded file can match the video out on the camera, we can dial in a CDL live and push this on to editorial, provide it as meta data for FX and then provide it as meta data for the final colorist. I am avoiding working with LUTs because I want every department working with the negative to be able to read the files and have the process automated. I understand that coloring after the fact would obviously make post easier, but the goal here is to ensure that the way the DP likes to work can still be maintained.

Cheers,
Jesse
 
Dan Kanes said:
I have used Pomfort livegrade in the following way to great success in conjunction with Davinci Resolve.

Set Dragon to Redlogfilm Gamma
feed SDI into Blackmagic HDLink Pro being driven by Pomfort Livegrade.

Export CDL LUT.

Load Lut into Davinci Resolve.

Apply LUT to Dragon Material

Generate Dailies.

Done.

Works great. Really great with Dragon.
Click to expand...

This is the preferred method however the issue is that at the camera there is only one gamma space. If I get RLF at my cart and the operator gets it in the EVF which is not great, not to mention a guaranteed complaint from the dolly! End running around it with metadata control onboard is workable but kind of aggravating. There hasn't been a truly perfect solution to this type of workflow yet. The ALEXA works so well in this regard because of its ability to output different gamma spaces on each tap but even it runs out of steam if you record ProRes in 2K - it mirrors the monitor path out the REC taps.
 
So Mark, when you were live grading I am assuming that means you were not seeing the same image live on your monitors that you would have been rendering for dailies... I assume you considered what you had delivered as a look (CDL) for dailies processing, a "starting point" for your colorist or DIT? This kind of defeats the purpose of live grading if you ask me.

I just ran the original test I had drawn a diagram of in my original post and it is definitely different. Which means that even if I were to use FoolControl, live grade, truelight...or anything for that matter if monitoring out of the cameras SDI....we would not be seeing an accurate portrayal of how the dailies will be rendered, how FX see's the color, how final color will see there reference, yadda, yadda...

I am curious if this will ever be fixed?

Cheers,
Jesse
 
You must log in or register to reply here.
Back
Top