ISO vs FLUT

[Mikael Lubtchansky]

Well, there you go Graeme. That is what I'm talking about. Why can't you or Red just come out and clearly state, that FLUT and ISO are exactly same thing, except FLUT has finer ISO control and it has nothing to do with changing the curve? Hasn't it been over a year for FLUT and people are still confused...

FWIW from the REDCINE-X PRO manual :

FLUT CONTROL
Once the preferred ISO is set, the FLUT level allows fine-tuning of the ISO level. FLUT control units are in stops, so +1 FLUT Control is the equivalent of brightening the image by one stop or doubling the ISO value.
Range -8.0 to 8.0, Default is 0.0

 

[BigLu]

From the very beginning I was not confused on FLUT, nor were the REDucation alum.
When we asked
It was always stated and made clear to all of us that Flut was a refined way of adjusting the inbetween ISO.

If going from one ISO to another was not quite what one was looking for, just went a touch to far.
Adjusting the flut a touch often did the trick inbetween ISOs.

Works wonderfully.

 

[jake blackstone]

FWIW from the REDCINE-X PRO manual :

FLUT CONTROL
Once the preferred ISO is set, the FLUT level allows fine-tuning of the ISO level. FLUT control units are in stops, so +1 FLUT Control is the equivalent of brightening the image by one stop or doubling the ISO value.
Range -8.0 to 8.0, Default is 0.0

Fine. So it is in the RCX manual. Although I don't think that it is nearly enough nor is it a best venue in explaining ALL of the Red metadata settings, like FLUT , Alchemy or how RedColor differs from RedColor2 or RedColor 3, I'll leave it at that. And BTW, how does it all jive with ACES? Will we need to use different ACES profiles for RED?
I had never needed to use FLUT, as I always felt it was created as a solution to a problem, that never existed. All FLUT succeeded is in creation of a lot of confusion. A third of a stop of ISO adjustments are plenty fine...

 

[N_Villers]

Jake, what exactly is your problem here? Are you really asking a question or just trying to make an issue where there isn't one. I think most of us who use redcine often have known what flut is and I for one find it quite useful as a quick way to control the brightness of the midtones. Can one do the same thing other ways? Of course. But its quick and simple which if you are grading dailies on set is good. Please remove yourself from your high horse or get lost. There is adifference between helpful criticism and just nagging.

 

[Rob Ruffo]

Yes of coarse it is better to use RedLogFilm instead of RedColor2 or upcoming RedColor3 for highlight protection. But what does it have to do with question at hand, that after all this time, since FLUT was introduced, there is still huge number of people, that are confused by what FLUT is?

Redlogfilm is a gamma, Redcolor is a color science. You can use Redlogfilm and Redgcolor 1, 2 or 3 together.

And Jake - setting Flut/ISO as precisely as possible via RAW settings is the best idea for Max richness of data sent to Davinci RGB system.

I agree with you on Alchemy - I'm not sure what it is and it seems to have no purpose if you are doing serious grading later in the chain. I also dislike the "try and it and see" explanations. I have no time to waste playing around without understanding what I am doing, and do not feel that this is a professional approach to workflow, which should be more oriented toward mindful and deliberate planning based on real knowledge.

 

[jake blackstone]

I for one find it quite useful as a quick way to control the brightness of the midtones. Please remove yourself from your high horse or get lost. There is adifference between helpful criticism and just nagging.

Your post, N-Villers is another display, that users are still confused. FLUT has nothing to do with mid tones. NONE. If you want to adjust midtones, just move ISO down and adjust your midtones. That is what midtones control is designed for. And a third of a stop for dailies is not enough precision for you?
I will ignore the obnoxious tone of your post and I'll address the underlying question. I'm choosing to address it, because, it is coming from someone, that lives in a country, that had long suffered under the oppression of Communism and where the uprising in 1968 was brutally put down. You, my friend, should know better, that you should always question authority and allow the opposite point of view. Blindly following the party line never ends well. So, I suggest you need start thinking on your own and learn some manners.

 

[jake blackstone]

Redlogfilm is a gamma, Redcolor is a color science. You can use Redlogfilm and Redgcolor 1, 2 or 3 together.

And Jake - setting Flut/ISO as precisely as possible via RAW settings is the best idea for Max richness of data sent to Davinci RGB system.

Yes, I know Rob.
That wasn't the question. Have you ever seen what kind of gamma curve RedLogFilm is. All I know, that it is close to Cineon. And, if that the case, why do i always need to bump the saturation for the image to match RedGamma2?
Like it or not, but whenever Kodak (yes, that Kodak, that just went bankrupt) released a new film emulsion, they would provide white papers and every imaginable information on it, so all manufacturers and users will be on the same page with no surprises and confusion. I'd like to see Red starting do that too. RedColor 3 is coming out soon. Do you want to start taking bets as to how much info we will get on that?

 

[paulherrin]

we love you jake.

thanks for clearing that up graeme. it makes sense now, that the adjustments are just following along the curve whether you take big or small steps. i think with the hype surrounding it when it came up, there may have been a little confusion about such technical details. kind of like alchemy... i am with you, jake - i would like to see some spiffy graphs and stuff. i feel like, as red becomes more established against competitors, they will play their cards a little more openly in the technical realm. i'm sure they have their reasons for lack of transparency in such areas.

 

[jake blackstone]

we love you jake.

thanks for clearing that up graeme. it makes sense now, that the adjustments are just following along the curve whether you take big or small steps. i think with the hype surrounding it when it came up, there may have been a little confusion about such technical details. kind of like alchemy... i am with you, jake - i would like to see some spiffy graphs and stuff. i feel like, as red becomes more established against competitors, they will play their cards a little more openly in the technical realm. i'm sure they have their reasons for lack of transparency in such areas.

Well, that was most unexpected, Paul. I was just getting ready to crawl back under the rock))

 

[Graeme Nattress]

Where info is necessary we're incredibly open. For instance "Have you ever seen what kind of gamma curve RedLogFilm is. All I know, that it is close to Cineon." - yes, it's precisely to Cineon spec thus:

const float cinGamma = 0.6f;
const float cinBlackPoint = 95.0f;
const float cinWhitePoint = 685.0f;

And is hence linearizable via the default settings in Nuke, for instance if you need linear light data from a REDLogFilm file, and thus will precisely match an EXR export from our tools. Similarly after VFX you want to match your linear light back to RLF for grading you just apply a standard lin2log node in Nuke.

"why do i always need to bump the saturation for the image to match RedGamma2" - you don't. You can match RG2 to RLF precisely via a single 1D LUT because that curve was designed with such a use-case in mind.

We're always happy to help any production with technical enquiries and supply this kind of information when asked. We do this all the time for productions big and productions small.

Jake - there's a vast difference from you not using something "I had never needed to use FLUT, as I always felt it was created as a solution to a problem, that never existed." - to nobody needing it. Locking ISO to 1/3 stop increments is like locking gain in traditional Lift / Gamma / Gain to 0.1 increments - it's an arbitrary and unnecessary limitation. There are tools in RC-X for those that want to do raw development to produce a pleasing image, and there's tools for those that want an image to go onto further grading in a dedicated app. That you don't see the need or use for a tool doesn't mean it's useless to other RED users. RED users are more than just traditional film or video users, so we cater to a rather broad church.

Graeme

 

[jake blackstone]

Where info is necessary we're incredibly open. For instance "Have you ever seen what kind of gamma curve RedLogFilm is. All I know, that it is close to Cineon." - yes, it's precisely to Cineon spec thus:

const float cinGamma = 0.6f;
const float cinBlackPoint = 95.0f;
const float cinWhitePoint = 685.0f;

And is hence linearizable via the default settings in Nuke, for instance if you need linear light data from a REDLogFilm file, and thus will precisely match an EXR export from our tools. Similarly after VFX you want to match your linear light back to RLF for grading you just apply a standard lin2log node in Nuke.

"why do i always need to bump the saturation for the image to match RedGamma2" - you don't. You can match RG2 to RLF precisely via a single 1D LUT because that curve was designed with such a use-case in mind.

We're always happy to help any production with technical enquiries and supply this kind of information when asked. We do this all the time for productions big and productions small.

Jake - there's a vast difference from you not using something "I had never needed to use FLUT, as I always felt it was created as a solution to a problem, that never existed." - to nobody needing it. Locking ISO to 1/3 stop increments is like locking gain in traditional Lift / Gamma / Gain to 0.1 increments - it's an arbitrary and unnecessary limitation. There are tools in RC-X for those that want to do raw development to produce a pleasing image, and there's tools for those that want an image to go onto further grading in a dedicated app. That you don't see the need or use for a tool doesn't mean it's useless to other RED users. RED users are more than just traditional film or video users, so we cater to a rather broad church.

Graeme

Graeme.
Sometimes I feel that we're talking past each other.
If people find the need for finer control, than 1/3 of a stop, fine. Personally, I don't. But that is not the point I'm trying to make.
There is a clear need for a centralized location, where all answers to these these questions can be found without scattering RedUser or RCX manual or calling Red. I understand, that in todays competitive environment there is a need to keep certain cards close to the vest. But the controls definitions, certain technical specs, curves, graphs, sizes etc should all be published and disseminated in concise way, where they can be easily found.
Just look at he way Kodak does it. It really is not that difficult.
http://motion.kodak.com/motion/Products/Production/index.htm
I know, I'm not supposed to bring up ARRI, but look at all info they provide:
http://www.arri.com/camera/digital_...nloads&cHash=234fb5a4a82bc3300222f5d4bf75c009
It really as simple as that

 

[Graeme Nattress]

Well, I think for controls in RC-X that the RC-X manual is quite the appropriate place.... For the more complex questions a real person beats a static pdf. I understand your desire for documentation for certain things. I will be soon writing a document detailing the temperature storage requirements for REDGamma3.

Graeme

 

[jake blackstone]

For the more complex questions a real person beats a static pdf. I understand your desire for documentation for certain things. I will be soon writing a document detailing the temperature storage requirements for REDGamma3.

Graeme

I'm not talking about complex questions. For those types of questions RedUser had been wonderful venue and will continue to be. I'm talking about fundamentals, that shouldn't require asking on a public forum and then wading through many answers not quite knowing, if they are correct. From very start of this topic, my point was, people are confused about FLUT and as such, I'd like a definitive explanation on it. Yes, you had answered it, repeatedly, for which I'm thankful. But the problem still remains. There is a need for a centralized library of Red knowledge, where users will be able to find the appropriate temperature storage requirements for REDGamma3

 

[jake blackstone]

Well, I think for controls in RC-X that the RC-X manual is quite the appropriate place....

Not if you're operating, say, Resolve. Here is the Resolve's explanation of FLUT:
"The Floating Point Look-Up Table controls operate within the new color space to give cleaner and finer ISO and mid grey variation without introducing clipping. Use in conjunction with ISO"
I believe, BM implies, that FLUT affects only or mostly mid tones , while preserving highlight. If BM is confused, then what about the rest of Red users? And is FLUT really a "Floating Point Look-Up Table"? Nowhere do BM mentions, that FLUT and ISO are exactly the same thing, only with FLUT having finer controls.
I think I made my point...

 

[Graeme Nattress]

Well, seriously Jake. I didn't write the Resolve manual.

Graeme

 

[Michael Millichamp]

Jake, I think your questions are confusing more people.

 

[jake blackstone]

Well, seriously Jake. I didn't write the Resolve manual.

Graeme

As I said, for some reason we're talking past each other. I'm going to cease now...

 

[N_Villers]

Your post, N-Villers is another display, that users are still confused. FLUT has nothing to do with mid tones. NONE. If you want to adjust midtones, just move ISO down and adjust your midtones. That is what midtones control is designed for. And a third of a stop for dailies is not enough precision for you?*
I will ignore the obnoxious tone of your post and I'll address the underlying question. I'm choosing to address it, because, it is coming from someone, that lives in a country, that had long suffered under the oppression of Communism and where the uprising in 1968 was brutally put down. You, my friend, should know better, that you should always question authority and allow the opposite point of view. Blindly following the party line never ends well. So, I suggest you need start thinking on your own and learn some manners.

Well... Jake thanks for escalating what I admit was on my part a sharp response. However, you are wrong on several points.*

First: changing your ISO affects your mids in the same way flut does without the fine control it has. And yes I do like finer control than 1/3 stop and often dial in .01 changes to get it right where I want it.*
Second: I live in a country that revolted against the Soviets in 1956 not 68.
Third: I am much more worried about the current political situation with the present right wing goverment here than trying to relive the situation of over 20 years ago. I am very vocal in supporting democracy which is facing with the present goverment perhaps the greatest threat to basic rights of any country in europe.*
Fourth: I responded much more to the tone of your posts than the content. I have never nor would I ever criticise someone for questioning authority. I don't think that is what you are doing. You have highjacked a thread that was based on a question regarding the difference between iso and flut that was answered in a quick and descriptive manner. If you don't like the tools then don't use them but again it is the tone that says "I'm the authority here" that bothers me. In all the energy you spent writing the above posts actually what meaningful info or criticism have you added? Honestly, do you really believe that this is productive?

 

[jake blackstone]

Well... Jake thanks for escalating what I admit was on my part a sharp response. However, you are wrong on several points.

First: changing your ISO affects your mids in the same way flut does without the fine control it has. And yes I do like finer control than 1/3 stop and often dial in .01 changes to get it right where I want it.
Second: I live in a country that revolted against the Soviets in 1956 not 68.
Third: I am much more worried about the current political situation here with the present right wing goverment than trying to relive the situation of 20 years ago and longer. I am very vocal in supporting democracy here which is facing with the present goverment perhaps the greatest threat to basic rights of any country in europe.
Fourth: I respinded much more to the tone of your posts than the content. I have never nor would I ever criticise someone for questioning authority. I don't think that is what you are doing. You have highjacked a thread that was based on a question regarding the difference between iso and flut that was answered in a quick and descroptive manner. If you don't like the tools then don't use them but agsin it is the tone that says "I'm the authority here" that bothers me. In all the energy you spent writing the posts above actually what meaningful info or. Criticism have you added? Honestly, do you really believe that this is productive?

Well, actually, believe it or not, originally I wrote 1956, but then for some reason, I changed the date to the date of Prague Spring of 1968. So, forgive me for not keeping up with Eastern European uprising dates
I guess you so hellbent on calling me out, that you couldn't be even bothered to read my earlier post, that showed, that even BM is confused about FLUT. But I guess, to you it doesn't matter. You just keep doing your goostepping and call yourself a democrat, while not allowing a dissenting view. If you're a democrat, I have very little hope for a future of democratic Hungary. Just look a bit farther back in Hungary's history around, oh say, 1940 or so. History has funny way of repeating itself
And this is absolutely my last post on this subject...

 

[jake blackstone]

And yes I do like finer control than 1/3 stop and often dial in .01 changes to get it right where I want it.*

I know, I know. I did say it was my last post, but I just noticed you said you dial FLUT in .01 increments? So I had to ask
.01? Or did you mean .1? It's got to be a mistake, right? Can you even see the change of .01 of a stop?