Resolve Grade: 10 mins of life gone...

[paulherrin]

If you target digital cinema, you can work in that space natively, in which case you wouldn't use an output LUT other than for projector or monitor calibration.

apparently folks are using these luts as presets for a 'film-look'

 

[Patrick O'Sullivan]

As I said in the warning before the little clip please don't take anything seen as the right way to do things. Yes this LUT and the others in the pack are designed as film emulation LUTs and as many have pointed out in this thread (the majority with more experience than myself...at least I think....maybe just being optimistic) it would have originally been designed to be plopped on the end of the tree and then flicked off before output.

Wow. Edit. Please see latest post for update. hehehe

If you aren't doing a film out or calibrating something a LUT is a pre-defined look. Use it however you want. I wanted to mix things up and switched from using an Arri LogC LUT to using this to get into a REC709 sort of feel. I did that because I'm used to grading Rec709 footage. I'm comfortable there and thats what my set up is desogned for. Yea I could do it by creating my own S curve and adjusting the saturation of each color but at what cost? Just because it is called a film emulation LUT means nothing. If I renamed it something like Log2HD_Rec709_Official_RED and re-posted it here as my own perfect REDlog starter LUT no one would ever know it was a film emulation LUT. My point is you can't tell from applying it. It is just like any other transform. Apply it and if you like what it does or if it saves you some time run with it.

If you are outputting for a DCP or broadcast and you are getting these things and have no idea what they were actually meant for then you may want to dig a little deeper. Or ask some more questions. Or hire someone who may know a little bit more.

I can't speak for anyone else but I don't try and get a 'film look' out of using these. I'm just lazy and can't be bothered making my own up or doing a shot by shot curve and adjustment. I think it looks better with the LUT than without. That is as simple as it gets. Makes my job easier.


I'm glad to see that people have their opinions. As I said everyone is right and everyone is wrong.

 

[Patrick O'Sullivan]

PS - if you want the real film look I've got a tip:

Go into iTunes. Find the 'film' look amongst the trailers you like and download the clip. Bring it into Resolve and match your shots accordingly. There is no secret sauce. The scopes dont lie. They are like source code view for web designers. You can't hide anything. It is all there. If you can't get there then you know one of two things:

Either you need to practice your grading skills

or

you need to practice your lighting/shooting/set design/wardrobe/the hundred other jobs in your average 'film' look piece.

 

[Juan Melara]

Great video. It's always good to see different grading workflows, I always pick up something new.

The problem with applying the LUT on the first node is you're losing a lot (if not all) of the benefits of grading in log. And with regards to the print LUTs you're losing the way the LUTs treat the rolloff into the highlights and shadows.

Although not evident in the example in the video, you'll also be losing a fair bit of information in the highs and lows due to the way the LUTs roll off both, which can be difficult if not impossible to bring back in subsequent nodes.

Same thing is happening to the colours. The LUTs tint the shadows green/blue and remove a fair bit of the saturation. No matter what you do to your shadows, those colours are gone. Apply the LUT at the end and all you need to do is increase the saturation and those colours can push through the green/blue tint.

Here is an example of this with regards to the highlights. Left image is the print LUT applied on the first node, right image is the print LUT applied at the end. The top images look identical. But bring down the gamma on both you can see a huge difference. As you can see the detail/colours you crush in the first node never come back. Not a problem when the LUT is applied at the end. I don't think anyone would say the prefer the left result over the right!

Ok so you could make sure that nothing is being crushed in the first node by adjusting the footage in the raw tab. But this is actually happening to all your detail/colours at every luminance level not just in the highs (or lows) - which is definitely not what you want!

Try grading and putting this LUT on the end. See what happens. You will have to double LUT because pulling a key off of the Log file is going to be fun. And what is the other LUT? You guessed it, a pre-defined look. Try not using a LUT and normalizing the image in the first node. You see what has just happened? You had to apply a look to normalize your image in the first node. Catch 22.

Qualifying a secondary from a log image is only slightly different to doing it with a REC709 image. It's not really anymore difficult. And in fact applying these Print LUTs on the first node can actually make keying harder as you lose a lot of colour contrast. 2 hues that are very different can be unified into almost the same hue making it difficult to key one from the other. Apply the LUT last, and the contrast between the two hues is kept intact.

Now if these LUTs were emulations of negative stocks you would want to use them on your first node (or load them as the input LUT). As you would want to work with your digital footage as if it had been shot on negative film. In this case, that makes a lot of sense. Of course this is assuming the LUTs are only performing a colour transform. If they are also converting your footage from log to video gamma, then applying them on your first node is still a bad idea.

 

[Joel Arvidsson]

Looking forward to se a version with the lut at the end, but keep it on and dont turnit off. Enjoyed your posts as usal. Thanks mate.

 

[Patrick O'Sullivan]

Juan you make some good points there regarding saturation levels and tints coming through downstream. I understand what your saying and agree in terms of image data being impeded later on. But then again that is what creative color grading is. We are suppresing what we don't want more of and pumping up what we do.

The photos show a case where the LUT is more effective if you were doing a single node grade and wanted that effect. I am trying to get across that these are presets. They are now used for looks if they aren't used for calibration. Like you said you get some tint and some sat loss. If you are educated and understand the ramifications of that then you can grade away with that knowledge. If you aren't aware of the offsets then you are in trouble.

These LUTs add to the quiver of creative possibilities.

As you mentioned these LUTs do have a heavy hand on rolloff and shadow tint. Armed with that knowledge you can either use it to your creative advantage or not. If I put the LUT at the end I would have had to preform other operations upstream to make my image match identically to what I left it at in the original. It is a push pull and no matter where you push you are eventually going to have to pull.

PS - good tip on the specular highlights. I was using a luminance key before but wasn't employing the log range manoeuvre. Thanks.

 

[Patrick O'Sullivan]

Looking forward to se a version with the lut at the end, but keep it on and dont turnit off. Enjoyed your posts as usal. Thanks mate.

I'll post up the shot of a post LUT application when I get in the office.

It will obviously look different so no real point in comparing because I would have graded it to look like I already graded it. It just would have taken different steps upstream. Does that make sense? I am not going to like the change because I am going to try and then change it back to the way it ended up because that is the look I wanted.

The true test would be quickly redoing the grade to what I wanted it to look like using the post LUT and seeing which is more appealing. I may give that a go if I get some time and let you decide.

 

[Björn Benckert]

Patric, for the frame in your demo I would probably done something similar as you did since the shot was not to much of a challenge. But when the conditions are more harsh, bright light into the camera, burned out sky, harsh shadows, sharp highlights etc then you will benefit from going the other way around. Basically stay in log as long as possible and push the colors and contrast around while keeping these print emulsion LOGtoLIN LUT's in the end of your batch, then you get to do your grade in log and more important you will take fully benefit from all the Kodak or Fuji print color science. Off course it's totally possible to tweak the colors even after you flop the image over to lin, but there are some very delicate highlight and contrast protection built into these lut's that you then just leave behind.


This tip is even more valid if you have a lot of shots to grade, as these lut's use dynamic rounding for you highlight they will (if used at the end of a log tree) keep all your shots more even just as a film print would.

So basically when you are putting the LUT on the input node you miss the beauty of applying your color tweaks in log color space. Instead you get to do your Color adjustments to a color crunched image in linear colorspace.
Further more you then bypass most of the fantastic color science that took Kodak hundred years plus to develop for their print stock.

Again I do not know much about resolve, but I guess it's like Flame where some toolsets are not built to work in LOG, some of the keyers etc, but then it is absolutely worth while to use some straight log/lin and lin/log transfer nodes before and after each of those steps. to make the keyer and such kick as they should but still staying in LOG for the rest of the processing.

Edit: Did not read Juan's post before I wrote the above. Listen to him, he explains these things very clearly. And more important he actually uses the program in question. LOL.

 

[Patrick O'Sullivan]

Thanks Björn. For the LUTs and the outline on the workflow.

As I said to Juan you are right on the money with the log aspect.

For the sake of completely inaccurate science I ran through the grade with the LUT on the end. So you tell me which you prefer.

I didn't save the first DaVinci file so I was just going off memory.

Not meant to be matching. I'm going to remove the images in the first post and then I'll post the 4 different images (one redlog flat, one LUT-pre node tree, one LUT post-node tree, and then one personal LUT (aka Log2lin_HD_RED_Unofficial). You tell me which one you like the best and we will have unscientifically made things even more confusing.

Here we go:

A.

B.

C.

 

[Joel Arvidsson]

I like a the most but im not looking at a good monitor. The others looks little more muted if you like.

 

[Björn Benckert]

I like the one that cuts best to the clip before.
Not to joke. They all look good. I would definitely not be able to tell whats what, to do so you need something thats shot with greater challenges involved.

I'm not trying to force any standards upon you or any one else. But to me grading from RAW in LOG is a wonderful thing, then that first node flipping it over in LIN kind of kills all the good stuff for me. How the result looks on a given frame going one way or the other does not mean much.
As a comparison you could probably reach the same looking result even if your source frame was dipped into 8 bit jpg before entering the batch, but that does not prove 8bit jpg to be the best source to start from.

 

[Patrick O'Sullivan]

Sorry for the confusion folks. Just came across a little tidbit. In all my testing I was always running the LUT last. hehehe. I was using the LUT tab in the setup menu and was always sticking it in the Output tray. It was only in the little video where I wanted to show people where to find the LUT that I put it first. I misunderstood where the OUtput tab was placing the LUT in the tree.

I'll have to add a note on the video.

Cheers

 

[Patrick O'Sullivan]

As a comparison you could probably reach the same looking result even if your source frame was dipped into 8 bit jpg before entering the batch, but that does not prove 8bit jpg to be the best source to start from.

Haha. very true. hence my sarcasm referring to how unscientific it all is.

Thanks again for making me go back and double check my settings. That is what these forums are all about.

 

[Eric Z]

Patrick,

Option A looks best to me.

 

[Joel Arvidsson]

Since there is many flavors of say the kodak luts. Do you flip throw them to find the most pleasent for that scene or is it any good advice you could give?
Edit: I know I seen the answer before and just found it.

Rob - ConstLclip, ConstLMap, CUSPClip refer to how the LUT treats colours that are out of gamut. For a detailed explanation read page 9 of this document.

 

[luigivaltulini]

thanks Patrick for tutorial...

 

[paulherrin]

didn't mean to say anything against your grade, patrick - it looks good (i like the fourth image myself - out of context) - and i'm personally less concerned with how someone gets a final image as what it actually looks like and why i'm seeing it. and that being said i have a long way to go technically and artistically myself: 'be the change you want to see', right?if anybody wants to use luts as presets or in any other way wants to emulate film for whatever reason that's fine by me.

i will note (and encourage everyone to explore) other grading philosophies that are not meant to 'look like film' - and one way i think about these is in allegory to movements of visual art like romanticism (film-look/photorealism), futurism (video-look/pseudorealism), and other words like surrealism, hyper-realism, magical-realism and other ways of attempting to capture the essence of 'truth' in the relationship of reflected light and shadow. appropriate sub-forum and software... check out davinci

 

[Jon MIchael Puntervold]

[FONT=Tahoma, Calibri, Verdana, Geneva, sans-serif]Patrick, thank you for a very nice informative tutorial. Nice introduction to colour grading on Resovle![/FONT]

 

[Christopher Barrett]

Would this be the appropriate Resolve LUT workflow?

In Project Settings

Camera Raw Tab: Decode using Project and set Gamma to RedLogFilm
LUT Tab: set 3D Output Lookup Table to preferred film LUT?

This seems to apply the same look as doing it in a node but as I reason would be at the end of the pipeline and you could change LUTs project wide with a couple clicks.

First time I've ever tried this workflow, so corrections appreciated.

CB

 

[Shane Daly DP]

Nice job Patrick, thanks for the demo. Can you talk a little bit about tracking windows? My auto tracker seems to have a mind of it's own!

Thanks.