Why use "don't affect colors" when you lose all color mapping control?

V-Ray for 3ds Max V-Ray for 3ds Max :: General
1

I have gone both ways using a linear workflow (max gamma settings to typical 2.2 settings)…

1) Linear mapping with “don’t affect colors” enabled, sRGB in VFB enabled, and not being able to adjust vray color mapping settings and;

2) “Don’t affect colors” disabled, sRGB disabled in VFB, and having many more color mapping options and control (while still maintaining a 2.2 gamma workflow)

I have yet to have someone tell me how losing color mapping options, being stuck with linear mapping and having no control of multiplier and burn values, is really an advantage.
Is there that much more, if any, noise in the shadows caused by “dont affect colors” being disabled, even if your other settings stick to the LW rules?

I prefer to leave it disabled, leave the sRGB button off in the VFB, and have color mapping control. Am I totally wrong doing this??

Any insights??

2

You can do it any way you want…and any way that fits your needs best. The point of going linear is to have a linear image. Which you don’t have if you bake in any color mapping or color correction.

Regards,
Thorsten

3

ok…so let me ask this…What does it really mean to have your mapping baked in? In other words, if I use linear mapping in both cases (set to 1,1,2.2), and, in one instance, enable “don’t effect colors” and enable sRGB in VFB, and, in the second instance, disable “don’t effect colors” and disable sRGB in VFB, I end up with exactly the same image on my screen. Now, in the first instance, I have to override my output gamma (which is 1) and set it to 2.2. In instance 2, I can leave my output gamma at 1. Now I end up with exactly the same image in Photoshop. Isn’t that baking gamma in as well?

What am I missing here?

dont affect color offdefaultoutput gamma 1.jpg
dont affect color offdefaultoutput gamma 1.jpg1280×720 140 KB

dont affect color ondefault output gamma 1.jpg
dont affect color ondefault output gamma 1.jpg1280×720 118 KB

dont affect color onoverride gamma to 2.2.jpg
dont affect color onoverride gamma to 2.2.jpg1280×720 146 KB

4

Well i guess it depends on the workflow and what kind of tools you work with. Photoshop can not work linearly. That sucks for many things. When using nuke you can work fully linear end to end. That’s great for many things, but not necessarily needed for everything. As a side note the images are not identical at all. The second one is darker then the third :wink:

5

I use photoshop not Nuke, AE or the others. I primarily focus on stills.

Because of that, perhaps I should keep my color mapping options available and not affect colors.

I’m probably placing too much importance on this subject anyway.

6

If your image editing software is Photoshop , it is best to avoid “Don’t affect color” option and work with sRGB data instead of Linear.

7

The reason I started using the first method you mention (as well as setting input/output gamma of bitmaps to 2.2), is that you can do batch rendering with various render elements using the max frame buffer. Can’t use Vfb with batch rendering - please read further…- because the render elements gets overwritten, although the RGB beauty passes are saved correctly.
If you use the second method (disable sRGB in VFB) and you render to MFB, you’ll get a double gamma (washed out image).

If you don’t worry about batch rendering of render elements, the look of the 2 methods will only differ in the shadows - vray calculates differently when enabling “don’t affect colors (adaption only)”.

When using other types of color mapping it’s a personal/artistic choice - Using linear workflow allows you to have less variables to set and being physically correct in terms of light intensity,distribution, etc.

8

Could you please inform us why do you have troubles with rendering in batch rendering with VFB - I just did a quick test and all render elements + beauty pass are saved separately - there are no overwritten images.

You can avoid this if you disable 3DSMax Gamma settings , and use Vray Gamma instead.

9

Well I setup my render elements, save my file in render output, click on save separate render channels.
Then I close the render setup dialog box and open up the batchrender dialog box to setup my different cameras.
When I hit batchrender, the rgb views gets rendered, but the render elements gets overwritten..

How did you do it - I saved my renders as tga/jpegs, not exr.

10

Could you please give more information about what “batchrender” are you using?
I have used Backburner in my tests - and it worked correctly (JPG file-type).

11

The default max batch render (located under the “Rendering” toolbar in Max) - There I setup x amount views and render out..

12

You are actually rendering different Cameras - not animation right ?
Are you using different names for the output files for each camera ?
A step by step instruction how to reproduce the issue will be very helpful.

13

Leaving the office now for a long weekend but will give a run through asap.

14

Step by step:
1.Setup x amount still cameras and render elements - save output tga., jpg. etc in render output
2.Close render output dialog box and open the max batch render dialog box - add various cams
3.Disable Vfb - using max frame buffer for final renders - max automatically numbers and name every camera’s view and render elements

If I use VFB and I set up the render elements to render out separately, I can’t use the batch render method as each cams render elements gets overwritten by the next cam’s render elements - have to then wait for each render to finish, rename the render elements for the next cam and render.

Hope this clarifies the problem.

15

Thank you very much for your feedback.
I managed to reproduce the issue , and I am going to report it in our bug-tracking system.
I’ll inform you as soon as we have a fix for it.

16

Thanks Svetlozar - glad you could reproduce this issue! To be honest I’m surprised I haven’t seen other posts relating to this problem?
Looking forward to a fix.

17

To continue with the “Dont affect colors” discussion, this is something I’ve been looking into today.

Like Daniel, I’ve been looking into the controlling the dark and bright multipliers, and colour mapping types, to give control the images. So to do this, using a workflow where Dont affect colours is unticked is the only way, right?

For me, the set-up is -

3Ds Max - Gamma 2.2, Input Gamma 2.2

A) Vray Color Mapping - Linear Multiply, Gamma 1, Dont affect colors un-ticked, SRGB on in VFB, exr files saved through VFB.

So from what I’ve read, this burns in the color mapping to the images.

The alternative to stop color being burned in is to use these settings -

B) Vray Color Mapping - Linear Multiply, Gamma 2.2, Dont affect colors ticked, SRGB on in VFB, exr files saved through VFB.

Both images render the same as in terms of colour and passes, so I’m slightly confused as to the differences with color mapping.

However the really interesting part that I’ve noticed is that with settings B, there is far less noise in the render, but the render times are longer. If I adjust the noise threshold of settings A to match the render time of setting B, the noise levels are very close, so there isn’t any advantage in render times, or noise, for either setting.

Can anyone explain which colour mapping method is best, and why? And also why the noise is calculated differently?

Thanks,
Dean

18

Well that’s the whole point of “Don’t affect colors”: To make color mapping not affect color. It DOES affect the sampler still tho, which is why you are seeing less noise.

If you plan to burn in color mapping because you actually use color mapping it does not really make much sense to use don’t affect colors. It makes sense if you want to render out LINEAR non-color-mapped images and still get proper sampling (It would be less efficient to just turn up the settings because linear vs. sRGB is a non-linear transformation obviously).

Regards,
Thorsten

Edit: In regards to the first settings burning in color mapping: Yes these settings do. But your color mapping settings are linear, so nothing gets changed or baked and only sampling is the only difference left for the two versions.

19

Dean…as for your option A…it should be "linear multiply (or any other color mapping your prefer), gamma 2.2, don’t affect color “un-checked” and sRGB “un-checked” on VFB.

I like to use the aforementioned settings because I can switch to Reinhard mapping and adjust my burn value to get rid of hot spots etc. I, personally, like to have the additional flexibility.

20

Dan, with your “linear multiply (or any other color mapping your prefer), gamma 2.2, don’t affect color “un-checked” and sRGB “un-checked” on VFB” settings, the exr files render with gamma applied (too bright), so can’t see how your set-up would work.

Thorsten, I think I’m starting to kind of understand the concept behind using “Don’t affect colors”. When this is ticked, the adjustments to the color mapping have no influence over the final rendered image, instead vray uses these adjutments to sample from, right?

So adjusting the dark multiplier (say I drop this to 0) would affect the samples in the dark areas? And adjusting the bright multiplier (increasing) would affect the light areas?
So is there an advantage in doing this instead of controlling noise through the noise threshold settings?

Sorry for all the questions, I’m just trying to see the advantages of using “dont affect colors”, almost ignoring the burn issue, but instead looking at noise, render quality and render time.

Thanks,
Dean