Author Topic: dubcats secret little hideout  (Read 109998 times)

2017-04-03, 12:51:57
Reply #30

miaz3

  • Active Users
  • **
  • Posts: 10
    • View Profile
@dubcat :

I find it strange to use LUT that is not related to the digital depth of the image rendered ?!
If I open the LUT there is only 32,768 correction line (2 ^ 15). But if you work on a 16bit image it would take 65,536 (2 ^ 16) lines of corrections ...
So why lost the half data ?
you are not actually losing anything, this is resolution of the mapping function, not the input data - even low-res mapping function can be used to transform high-res input data with no quality loss.

As an example: Corona VFB uses 32bit color format. If you change exposure, you are applying a transformation that could be expressed as 1 line LUT. But the output image does not lose any information

I meant, losing half data of bit depth of the LUT, not the raw. This LUT is just like a "film look" ?!
Is not totaly matching to the raw data (eg 16 bit or 32 bit) soulder and foot curves too.
Which causes either the floor noise will be processed, or the high values will not be processed by the curve. (And vice versa).


2017-04-03, 13:33:07
Reply #31

Correntes

  • Active Users
  • **
  • Posts: 92
    • View Profile
    • PRESSRENDER

[/quote]

With white color at 240 I presume the render times have fallen of the charts (super high), right?
[/quote]

a little bit yeah :S

i'm still testing

2017-04-03, 21:47:45
Reply #32

nkilar

  • Active Users
  • **
  • Posts: 852
    • View Profile
    • My personal website


With white color at 240 I presume the render times have fallen of the charts (super high), right?
[/quote]

a little bit yeah :S

i'm still testing
[/quote]

Well if the contrast is bothering you that much maybe playing around with the filmic settings could do the trick. Then again it might not :)

2017-04-03, 22:32:20
Reply #33

ASaarnak

  • Active Users
  • **
  • Posts: 36
    • View Profile
    • The Highlight
Thank you for sharing the LUTs :)

2017-04-04, 01:12:27
Reply #34

dubcat

  • Active Users
  • **
  • Posts: 460
  • ฅ^•ﻌ•^ฅ meow
    • View Profile
I find it strange to use LUT that is not related to the digital depth of the image rendered ?!
Maybe I'll release 64 sliced versions in the future, 41+ should be enough for what you want.

What cameras are used for the extracted LUT ?
I went into my Canon/Nikon folders and selected 3 random LUTs. I got a lot of Canon 60D LUTs in there, so one of them might be 60D.

Canon cameras have this magenta Tint to them, sometimes -10 green. This happens even if you calibrate the camera as perfect as you can. We need to use the sexy Tint feature in CameraRAW to get a perfect white balance. Since I'm dumping the real deal, I left this error in there. If you notice a slight magenta shift, it's a Canon LUT 99%.

Canons best friend.



and a big thanks to everyone else that has responded!
             ___
    _] [__|OO|
   (____|___|     https://www.twitch.tv/dubca7 / https://soundcloud.com/dubca7 ( ͡° ͜ʖ ͡°)

2017-04-04, 11:23:47
Reply #35

Correntes

  • Active Users
  • **
  • Posts: 92
    • View Profile
    • PRESSRENDER
Update:

I got it working and quite like the results

The 01b is the version with the luts and 210w 34b sRGB

2017-04-04, 11:55:35
Reply #36

Rhodesy

  • Active Users
  • **
  • Posts: 461
    • View Profile
Looks cool. When you say 34b is that 34 the lowest/darkest you set a black material or have I misunderstood? I assume the 210 is the white wall level?

2017-04-04, 12:00:13
Reply #37

Correntes

  • Active Users
  • **
  • Posts: 92
    • View Profile
    • PRESSRENDER
yes

max white 210 sRGB
max black  34   sRGB

2017-04-04, 13:13:02
Reply #38

Rhodesy

  • Active Users
  • **
  • Posts: 461
    • View Profile
Thanks. Good to know.

2017-04-04, 14:47:47
Reply #39

agentdark45

  • Active Users
  • **
  • Posts: 477
    • View Profile
Update:

I got it working and quite like the results

The 01b is the version with the luts and 210w 34b sRGB

Wow that's some difference. Are you able to post any of the post processing settings that you used in conjunction with the LUTs?
Vray who?

2017-04-04, 14:49:50
Reply #40

Ondra

  • Administrator
  • Active Users
  • *****
  • Posts: 8904
  • Turning coffee to features since 2009
    • View Profile
good news, the new LUTs are now bundled with Corona installer
Rendering is magic.
Private scene uploader | How to get minidumps for crashed/frozen 3ds Max | Sorry for short replies, brief responses = more time to develop Corona ;)

2017-04-04, 16:49:03
Reply #41

Correntes

  • Active Users
  • **
  • Posts: 92
    • View Profile
    • PRESSRENDER
Update:

I got it working and quite like the results

The 01b is the version with the luts and 210w 34b sRGB

Wow that's some difference. Are you able to post any of the post processing settings that you used in conjunction with the LUTs?

That's the beauty of it, get the exposure right, highlight compress an then I just  applied the lut at 100%, vignette, chromatic aberration, tweaked the white balance and that's it.
I do the post outside of corona due our layer workflow .

good news, the new LUTs are now bundled with Corona installer

That's wonderful news Ondra



2017-04-04, 23:42:20
Reply #42

miaz3

  • Active Users
  • **
  • Posts: 10
    • View Profile
Quote
Maybe I'll release 64 sliced versions in the future, 41+ should be enough for what you want.
I don't understand ?!
You deliver a LUT that was generated from 3 random LUT Canon dslr ... There is nothing logical in it ?!
Canon LUT are created for mapping Canon sensors, like arri, red et cie...
So what do not tweak a curve and that it ?! (ed: i just plot your LUT_03).

So here we've got a LUT that not mapping the raw data ? i'm not talking about 32 bit float raw, but just for this exemple 16 bit is enough.

It's that simple.
I just want to understand the interest of mapping a LUT that does not match the RAW's digital depth. Like dslr, or camera manufacturer do.



2017-04-05, 00:27:31
Reply #43

dubcat

  • Active Users
  • **
  • Posts: 460
  • ฅ^•ﻌ•^ฅ meow
    • View Profile
When you take a picture with your dslr in jpg mode, the raw goes through ColorMatrix, ForwardMatrix, LookTable and ToneCurve. That's what these LUTs do.
These should be applied in a specific order, since we can only apply one LUT and not 4 LUTs after each other in order, we can't get 100% match, but it's damn close.

I always take a color checker reference picture. This way I can control if the linear raw + LUT will match the camera JPG.

Here is one of my older Canon control tests.

Linear RAW converted to sRGB.



JPG from Camera



RAW + LUT (When you use dcraw to make a proper linear raw, it does not denoise the picture, so you will see noise on some colors, like purple)



Hope that helps you understand whats going on with these LUTs :)
« Last Edit: 2017-04-05, 00:33:51 by dubcat »
             ___
    _] [__|OO|
   (____|___|     https://www.twitch.tv/dubca7 / https://soundcloud.com/dubca7 ( ͡° ͜ʖ ͡°)

2017-04-05, 07:48:10
Reply #44

Hamburger

  • Active Users
  • **
  • Posts: 84
    • View Profile
THe LUT looks great for interiors, but with harsh sun + sky system it really is too much contrast and shadows are massively crushed. Does it work for anyone else?
Maya 2016
Windows 10