Burn

[glorybound]

What is the difference between the frame buffer's highlight burn and a burn value in the Color Mapping? Other than burning it into the image using the Color Mapping?

[Jiri.Matys]

I think its mostly the same. But one difference I know, when you use burn in VFB, bloom and glare still use bright pixels and these effects work great. When you use burn in color mapping settings, bright pixels will be darker for bloom/glare too and this effects will be much harder/impossible to set up properly.

[glorybound]

Yes, I found that part out. I also found that things do render faster with Color Mapping Burn on, but not when using the VFB. I guess like anything, there are pros and cons.

[Neilg]

set the color mapping burn to a low value -.3 or so, and change mode to 'none' so it doesn't bake it in to get the best of both worlds.

We do our color mapping in post after applying glows, i set up a fusion macro which is a little like the VFB with a glow, color balance, highlight compression & curves - it works great and offers a lot more flexibility to tweak.

[glorybound]

I did an interior with a burn of .3 and it was really flat and I lost ability to change exposure in PS. I'll try setting it to none.

[Neilg]

Use the burn value in the vfb when you have it set to none, itll be burnt out otherwise. The render you save out will be as if the burn is at 1, but the sampling and AA will have been performed as if it is .3

[jacksc02]

Hey Neilg Any chance I could have a look at your fusion macro?

[Jiri.Matys]

When you change it in color settings, you cant change it interactively. This is why its much better in VFB.

[DanSHP]

set the color mapping burn to a low value -.3 or so, and change mode to 'none' so it doesn't bake it in to get the best of both worlds.

We do our color mapping in post after applying glows, i set up a fusion macro which is a little like the VFB with a glow, color balance, highlight compression & curves - it works great and offers a lot more flexibility to tweak.

Would love to have a gander at this, if you would be so kind?

[Ihno]

jep, i'd also be interested.

[DanSHP]

Whilst we are on the subject on burn, something that has been bothering me for quite some time, is how to target blown out highlights when working in lwf.

One thing that Camera Raw in PS is good at (was good should I say since they removed its 32 bit editing capabilities forcing you over to LR, spits), was specifically targeting the really bright highlights within an image and toning them down in 32 bit. I'm aware this question has been brought up a few times down the years on here (using search) but I still haven't quite figured out how to have some control over it all.

See attached images. Quick example.

So from left to right, we have the blown out beauty pass, the same beauty pass with an exposure reduction (to reveal texture the information is there), and an image with a reduction of the highlights using the VFB. Whilst the blow may be physically accurate, I'm sometimes asked by clients to tone this down so we can see the material/texture, as represented in the reduced exposure image I've attached. Highlight burn, just looks ugly. What I want, is to be able have a beauty pass, and target that blown out area, reduce the exposure of it, to reveal the information that is there in 32bit, without affecting the rest of the image too much. This was possible in camera raw (even with that annoying curve adjustment i throws onto an image when used).

At the moment I have to create two versions of the beauty pass in PS, and use masks etc to achieve this (ala the fourth image upload). This ok for the most part on a simple scene like this, but when they are everywhere it becomes a bit messy!

[glorybound]

When you change it in color settings, you cant change it interactively. This is why its much better in VFB.

If speed isn't a factor then it makes sense to stay in the VFB, however, when I use the Color Mapping burn is where I see speed savings.

[Neilg]

I am planning to make a post about the entire setup, but the most important part is the tonemapping tools - I have 3. I did not create them, I collected them from forums.

Edit "MacroOperator" to "GroupOperator" if you'd like to unpack them and fuck around with the non macro version.

Hit the post limit, so they're at links

Reinhard - https://paste2.org/jsZhjapH

Corona highlight compression (very simple, good results) - https://paste2.org/KKmpsMMz

Filming tonemapping (complex but powerful) - https://paste2.org/LChgB58b

And an exponential glow (put this before the tonemapping. it's not quick but it's beautiful) - https://paste2.org/F9994E8E

DanSHP - can you share the raw exr of your first image? i'll see if these can handle it.

edit2: here's a quick comparison on an old test. it's not great but should give an idea of what they do. The real benefit comes from making color and level adjustments to objects using multimatte masks before color mapping and glow is performed - gives a much more reliable result. The glow is a bit crap, i didn't edit any settings and it is catching on too many things.

[kosso_olli]

I'm so hoping that the addition of the new VFB in one of the service packs will also bring some new tonemapping options. This is an area where V-Ray is way behind Corona, and miles behind fStorm, which has some of the nicest color mapping options of the current renderers.These days I spend less and less time correcting images in PS, I tend to do everything with the VFB and applied Luts. This however never gets baked into the image when saved, so you have to use the nasty Clipboard-workaround, which doesn't work in animations...

[DanSHP]

I am planning to make a post about the entire setup, but the most important part is the tonemapping tools - I have 3. I did not create them, I collected them from forums.

Edit "MacroOperator" to "GroupOperator" if you'd like to unpack them and fuck around with the non macro version.

Hit the post limit, so they're at links

Reinhard - https://paste2.org/jsZhjapH

Corona highlight compression (very simple, good results) - https://paste2.org/KKmpsMMz

Filming tonemapping (complex but powerful) - https://paste2.org/LChgB58b

And an exponential glow (put this before the tonemapping. it's not quick but it's beautiful) - https://paste2.org/F9994E8E

DanSHP - can you share the raw exr of your first image? i'll see if these can handle it.

edit2: here's a quick comparison on an old test. it's not great but should give an idea of what they do. The real benefit comes from making color and level adjustments to objects using multimatte masks before color mapping and glow is performed - gives a much more reliable result. The glow is a bit crap, i didn't edit any settings and it is catching on too many things.

Sorry for the late reply, i was away from the office for a few days. See attached zipped .exr. Will this do?