FS7: SMM SLog2 Vs Slog3

Doug Jensen said:
As for your attitude that anything goes "if it gets you where you want", that is total crappola and the lowest kind of argument in any discussion of techniques.
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No it is not an attitude it is my (possibly incorrect - im open to that) understanding of 32bit float image manipulation - certain tools are not more or less destructive to the image than other tools, nor the order (exluding LUTS) important.

PC from BMD took quite some time to convince me of that 'power'

Other processes in the video chain, for example taking a raw file, saving it as H264 then trying to alter the WB are clearly destructive.

Also there needs to be logic to workflow. In resolve for example I will keep 'art looks' and 'colour correction' on different nodes as that is efficient if the client does not like an 'art look'
 
morgan_moore said:
Offset vs Offset?

To be fair they are not identical.. I mull that :)

https://vimeo.com/227149321

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In that project you showed in video, create 2 serial nodes, apply any Log to R709 Lut on the last node (disregard what it does to the grey scale stripes image). Now select the first node and perform all the adjustments you showed in the video. Watch the WFM - can you see how differently everything behaves? Offset does not simply shift everything, it stretches the waveform. Now add a serial node after the last one with the LUT. Select it and do the same adjustments. To me it was eye opening.
 
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Assume 3 nodes, node two has a LUT.

I can clearly see the differences in working node 1 and node 3 - the changes in node one are 'pinned' by the LUT, while those in 3 are not..

what I cant clearly see is a difference between manipulating offset or log offset in node 1 (or three)

S
 
morgan_moore said:
Assume 3 nodes, node two has a LUT.

I can clearly see the differences in working node 1 and node 3 - the changes in node one are 'pinned' by the LUT, while those in 3 are not..

what I cant clearly see is a difference between manipulating offset or log offset in node 1 (or three)

S
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My understanding is that Offset wheel is exactly the same adjustment in Primary wheels/bars and Log wheels. Note that if you make changes to the Offset in Primary, then switch to LOG, the numerical values of this adjustment remain the same.
 
Im still lost.

Mainly Dougs assertion that I am (I paraphrase) a moron for using offset, not log offset.

I may well be a moron but Id like to know why so I can learn.

Seems like you are saying they are indeed the same?

I think my little video clearly shows exactly what each wheel/bar does unless Im missing something?
 
morgan_moore said:
Im still lost.

Mainly Dougs assertion that I am (I paraphrase) a moron for using offset, not log offset.

I may well be a moron but Id like to know why so I can learn.

Seems like you are saying they are indeed the same?

I think my little video clearly shows exactly what each wheel/bar does unless Im missing something?
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I don't think he was talking about Offset wheel / Offset master slider as it, in my understanding, does not strictly belong to either Primary or LOG, these are master adjustments. As noted before, if you change the setting of the offset wheel / offset slider, the numerical values remain the same regardless in which mode you are, unlike for the Lift/Gamma/Gain values which are separate for LOG and Primary, they remain specific to the chosen mode, you can see it by switching back and forth between modes. I may be wrong but I think he was referring to you using Lift bars adjustment in Primary mode on the firs node instead of LOG, and about your use of contrast and Curves adjustments in general.

You grey scale video does show what each wheel does but not in the right context. You have no node and no LUT applied, and you are not dealing with a LOG signal. As per my earlier comment, this as well as the order of nodes affects how the adjustments affect the signal.
 
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I have another greyscale which is 'faux' log and have played with that too.

AFAIK all the controls do what they do and in the 32 bit floating space they make no odds which is chosen.

For example changing contrast is no different from making a curve that changes the contrast

Using curves is no different from making a wheel adjustment that has the same effect.

--

Let us put it another way..

If you expose at 800 but your LUT is designed for 2000 how would you 'gain down' the image???
 
broughtonfilm said:
I don't think he was talking about Offset wheel / Offset master slider as it, in my understanding, does not strictly belong to either Primary or LOG, these are master adjustments. As noted before, if you change the setting of the offset wheel / offset slider, the numerical values remain the same regardless in which mode you are, unlike for the Lift/Gamma/Gain values which are separate for LOG and Primary, they remain specific to the chosen mode, you can see it by switching back and forth between modes. I may be wrong but I think he was referring to you using Lift bars adjustment in Primary mode on the firs node instead of LOG, and about your use of contrast and Curves adjustments in general.

You grey scale video does show what each wheel does but not in the right context. You have no node and no LUT applied, and you are not dealing with a LOG signal. As per my earlier comment, this as well as the order of nodes affects how the adjustments affect the signal.
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This is actually all wrong! Doug is right! The thing I wrote about Offset being the same is wrong! Primary offset overrides LOG offset when done on the same node. That's why it seems they are linked if you move Primary offset - the change is reflected on the LOG mode offset wheel. But it does not work both ways: change the Offset in LOG mode and switch to Primary mode - now the values are different, the Primary wheels Offset does not follow that in LOG. Makes sense as the Primary is a master offset and LOG, well... LOG offset!

This "children in a fog" struggle here confirms what I wrote in the other Slog vs Slog thread - not too many people know what they are doing grading Slog footage, and using Davinci in general!
 
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'I would consider offset to be my exposure tool' - Doug Jensen. (100.41)Doug Jensen's Guide to Grading Sony S-LOG & RAW in DaVinci

I just bought his resolve video - its always interesting to see other angles and I like Dougs formal approach to some things.

Less convinced by this thus far!
 
I have to say that I'm quite lost now. I thought I figured it out but again think these Offset adjustments are the same... A bit like "running in wheels" situation in my head now, or "my head spinning like a Davinci jog wheel"... Something about how LOG Offset and Primary Offset interact when used on one node which is probably something that does not make sense on one node.
 
Seems exactly as expected.

Lift gamma gain in Log are different from LGG in Primaries and Wheels

Offset is the same.

Thats what it says, thats what I say.
 
morgan_moore said:
Seems exactly as expected.

Lift gamma gain in Log are different from LGG in Primaries and Wheels

Offset is the same.

Thats what it says, thats what I say.
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Ok, got it. What confused me is the terminology. "Master wheel control" which I thought referred only to the wheel under the Offset balance wheel, but now I see it refers to every wheel under the Color Balance Wheels.
 
morgan_moore said:
Well what is right? Simple question how to get from the 2000 ISO overexposed look to 800 correctly exposed look?
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Is there a reason why you don't want to just create a 'set' of exposure-compensating LUTs using LUTcalc? I have a set that runs in 1/3rd stop increments from 1-under all the way up to 2-over, and simply toggle between them in DVR to correct intentional exposure compensations. This way you can even use the memory function to save shortcuts to a selection of nodes with, say, +1/3rd, +2/3rd, +1, +1 1/3rd stops and fly through your timeline de-logging and exposure-compensating all your clips via shortcuts before going back to start the grading proper.

-jason
 
Of course I might want those LUTs..

But how would you make them.. you still have to make the exposure compensation in resolve. (which you would then save/export as a LUT)

Simply Im happy with the offset wheel but others have suggested this was not the correct approach.
 
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