How to monitor a custom LUT with IPP2 RedWideGamutRGB and Log3G10?

[Alexander Sutton-Hough]

I have a custom LUT I like to use a lot for my narrative work and would like to be able to monitor it on my RED touch screen monitor but it can only be apply it on top of the Rec709 or Rec2020 display preset. The lut is built on IPP2 RedWideGamutRGB and Log3G10. I am using a DMSC2 Gemini Firmware Version 7.3.0

The only way I can monitor it is sending out a clean feed of RedWideGamutRGB and Log3G10 to my production monitor where I have the LUT installed to properly view it.

I called RED last summer and they said in IPP2 pipeline you can not apply a Lut for monitoring unless its on top of Rec709 and Rec2020 display. This is really is odd since even my little GH5S and black magic video assist and lots of cameras and monitors give you this option to apply a lut over the log mode for monitoring.

Does anyone know a way around this in Resolve or setting I am not aware of? I was hopping by now Red would come out with a updated to allow this since they have had bunch of people call and ask how to do this very basic task.

I just want to be able to properly build a LUT for IPP2 and view it correctly on RED.

 

[Alex Lubensky]

My guess is what you're asking is conflicting with the whole idea of IPP2. You don't need IPP2, IF you're going to place a LUT over LOG. It's done INSTEAD of IPP2 transform. On post you just pop-up your image with camera settings and apply your LUT, and work from there on.

 

[Bob Gundu]

Just go to Legacy Mode and switch on RedWideGamutRGB and Log3G10 and then apply the LUT to LCD Monitor and SDI.

 

[Alexander Sutton-Hough]

When I talked to Red the guy on the phone said I could do that using legacy. But also said recording in IPP2 has better processing with noise reduction and color vs recording in legacy in RedWideGamutRGB and Log3G10. Even if I shot it in legacy and switched the Raw to IPP2 in post.

 

[Bob Gundu]

When I talked to Red the guy on the phone said I could do that using legacy. But also said recording in IPP2 has better processing with noise reduction and color vs recording in legacy in RedWideGamutRGB and Log3G10. Even if I shot it in legacy and switched the Raw to IPP2 in post.

100% no difference in image quality if you record in legacy or IPP2. I confirmed this with Graeme Natress.

 

[Aaron Lochert]

When I talked to Red the guy on the phone said I could do that using legacy. But also said recording in IPP2 has better processing with noise reduction and color vs recording in legacy in RedWideGamutRGB and Log3G10. Even if I shot it in legacy and switched the Raw to IPP2 in post.

Bob's right. It shouldn't make a difference. You can always re-process material flagged with Legacy metadata to go through IPP2 and get all those benefits.

In fact, even recording to ProRes internally with IPP2 versus Legacy, you still won't see those benefits. The new noise reduction, the new debayer, and the new highlight extension algorithms are all left to the computer when you process the .r3d files with the latest software.

To the core of your issue: It sounds like you're developing a LUT with it's own gamma curve/transform to Rec709 built into it. Which by definition means it's not not quite IPP2. Remember, the full IPP2 pipeline includes the display output transforms (rec709 or rec2020 as the guy on the phone told you), so if you're designing your LUT to work in camera as an IPP2-specific LUT, it needs to be designed to be pre-output transform. If you're wanting to just work from scratch off the base Log3g10/RWG material and build in your own curve, then you've got Legacy mode or the workaround that you've found by applying LUTs on the external monitors.

 

[Mike P.]

When IPP2 launched I questioned why applying "none" to gamma output and roll-off does not look the exact same as RWG/Log3G10 in Legacy, as it logically should (instead the highlights go off the charts and it's even flatter)... Never got an clear answer/response. Had that been the case, these kinds of questions/concerns would have been easily avoided, without having people worry that their losing the benefits of IPP2 (it certainly would have been easier/all encompassing). Sure, it's easy enough to come on the RU and ask, but I doubt the majority of DoPs/camops are gonna do that (nor should they have to).

Conversely, pretty sure Panavision's DXL/DXL2 still defaults to Legacy pipeline to avoid these issues (or at least they used to). That's what the LiColour LUTs are expecting. Not saying that Panny knows better than RED, but they do support some pretty high-end productions with professional crew, so if they still see the need to simplify the process further that seems telling.