underpainting in 3D space

[Ernest Burden III]

Something I've often used in my CG rendering is the classic watercolor technique called underpainting, where you paint a color wash on your paper before putting on any other paint. The tones read through transparent WC washes and provide a nice sense of unity to the rendering.

 

The same can be done in CG by putting a colorfade OVER your picture in linearburn mode, set to a very low strength, like 5% - 20% depending on taste. This has the effect of darkening the picture which is both desirable and a bad side-effect. By using a copy of the colorwash layer set to 'color' mode and a very small strength, you can pull the tones without darkening. It is a technique based on the picture being a 2D image. Remember--renderings are not 3D environments anymore. They are pictures, and must work as pictures.

 

Here's a color wash I used on an aerial exterior, but seen by itself at 100%:

 

 

 

You can do something similar in 3D, and that's what I'm writing about.

 

When you have a scene, either interior or exterior, and you know how you want to show it, you have the opportunity to think about what areas will be darker, bluer, warmer. This should be part of your overall planning. Sure CG software can do near-perfect photorealism with everything everywhere the perfect tone. But that's so boring. Colors change with distance and color carries emotional cues. Use them to your artistic advantage. Color is fun.

 

Putting an underpainting in 3D is done by using lights that don't cast shadows. Put a color gradient in the falloff of a light, set it to not cast shadows and you're on your way. You will want to experiment with both diffuse and ambient-only lights to see what you like. Start with high-strength to see the effect, then tone it way down to just add that bit of extra life. If you want to push back the far corner of a room, shine some deep blue-purple on it, while the center of the room gets a near-white (no added color) fading into some yellows to warm up near-ground. I will put a light above a scene, often another shining up from beneath. One set to ambient (adds color without any gourand-like shading--like a flat wash) and the other to diffuse to begin to define some shapes within the colors. Both set to low strength.

 

Here's a project I just handed in, its a bar in Florida. These first images show preliminaries with no lighting but the color washes. I kept them to the end, but once the actual lighting is in, its not so noticeable.

 

 

The client wanted to show a 'low-light' setting, and I was determined to not lose color in the darkness. The whole place was black and dark materials, with brown-glass mirrors and panels of shiny metals arranged in random rectangles.

 

Another advantage to this was having even my early images to the client have the 'feel' I wanted rather than a bland gourand screengrab.

 

Another idea for bringing in color in 3D is to use an ambient occlusion shader set to a gradient and a very wide effect so that tight corners are dark cools, then ramps to light warms. It looks great, even for a simple, early model before you have ANY actual lighting in place.

[Ernest Burden III]

These are my finals for the bar, I'm really pleased with the result. So was my client:

 

 

 

 

Using light-cast colors works well for exteriors, too. These are animation frames:

 

[kippu]

i read about this in your site ..... very pleased that you are expanding it further from there ... do you use the same color washes ,, or you change it according to the settings ( am sure you change it ) .... let me experiment on it .... thanks again ernest

[STRAT]

i was interested in this when i downloaded this whole section from your site a few months back for lunch time swatting

 

i gave it a bash, but it obviously suits the freer watercolor style imagery you knock out rather than the conventional stuff i do.

 

Although, when i have the time, i'm so interested in modeling up my subject in wire frame, running a couple of water colour style filters over the lines, printing out on heavy knot water colour paper and physically painting the bulk over the top.

[Ernest Burden III]

lunch time swatting

 

I'm to be swatted, then? Is that a good thing?

 

Frankly, I didn't expect this technique to be of much interest to you since you've always said you prefer straight realism to my take on things. But if you want to follow along please keep up, we're in 3D now with the color washes. (I'm just joking around). In practice, the 2D Photoshop color wash is what I would use most of the time because it addresses a rendering as a picture removed from the 3D model environment. And that it's about the last task before calling the thing done, so you make your decisions with the most information in front of you.

 

But I'm liking the fact that I am incorporating color movement right into the model, and seeing it all the time while putting the scene together.

 

Where it get interesting, and this becomes an artistic choice, is that when adding color in 3D you are bringing tonal values UP, as in removing black by whatever strength you are projecting. This is especially true with an ambient-only light, but also with a diffuse one. The result is lowered contrast. Using Photoshop to add an underpainting offers either going sideways (color mode) by simply pulling the color towards your wash but leaving the luminance value the same, or darkening the result with linearburn. A little darkening towards the corners of a picture is an old and pleasing visual technique which I quite like, but your likes may vary.

[STRAT]

swatting must be an english term

 

it means intelligent reading. what students do before exams.

 

and yes, it's definately of interest to me as i like all forms of digital art. even if it doesn't suit my work regime. i plan on brushing up (no pun intended) my skills by taking my travel water colour paint set with me to NewZealand this Christmas whilst on vacation so i can log the views and sights on paper and paint rather than just photographs.

[Chad Warner]

It would be interesting to see Ernest's technique applied to a realistic style rendering, only to see if the same methods can be used with the desired results.

[Ernest Burden III]

It would be interesting to see Ernest's technique applied to a realistic style rendering, only to see if the same methods can be used with the desired results.

 

As you wish. I'll give it a try, post the result.

[Justin Hunt]

It is fantastic for bringing in a sence of mood and emotion to your images. Colour composition is an oft overlooked element in 3D renderings, resulting in sterile, boring images.

 

JHV

[Chad Warner]

As you wish. I'll give it a try, post the result.

 

Excellent! No one better to try it than the creator.

[landrvr1]

Ernest, great technique. Your work is truly refreshing and totally unique.

[Crazy Homeless Guy]

this is good. i have tried this a few times in the past, but i don't think i really understood what i was doing with it. ...or maybe i want to make sure i am understanding this right.

 

in the past i have just made large streak of either blues, purples or warm hues. i didn't respect the image much. meaning, i was not concerned with using the technique to control the eye. i might through some large diagonal streaks across a horizontal image.

 

i was just doing a wash for the sake of doing a wash. i was not thinking in the terms that an artist would set up a wash knowing what composition of the final image would be. the way i was thinking of underpainting had more to do with the way HDRI files work, than how the eye and the mind interpret space and focus....

 

..but in reality it is all about controlling space, focus, and center of interest? if this is true, then it has everything to do with those who do photorealistic images.

 

....i also wonder how this relates to studio lighting for movies or theater lighting.

 

....and also, what could be done with this when rendering an animation.

[Justin Hunt]

After reading the thread this morning I had a little play. Its a different methode but the results are interesting.

 

By changing the two colours of a Distance Blend, Fall Off map changes the focus and depth if the image.

 

Its subtle but effective

 

JHV

[Ernest Burden III]

By changing the two colours of a Distance Blend, Fall Off map changes the focus and depth if the image.

 

There are probably many ways to add color into a 3D scene, in 3D.

 

My problem with using ambient lights/no shadows is that FinalRender cannot render them while C4D does just fine. So I thought up another way. I'm using a gradient of my colors in the 'environment' channel, set it to not cause reflections on everything. Like the lights, it kills black, but it adds color the way I want. Unfortunately, I cannot get it to act like a light set to ambient, meaning it ADDS to light in the render while ambient-only works in multiply-like mode. Oh, well. This works in both C4D and FR2, though the scale of the 3D world-coords. gradient changes a bit, forcing me to change the values to switch between C4D and FR2.

 

Here's an example of a prelim with color pumped up:

 

[anvaraziz]

yup, its a good trick,

i used this mostly at the time of post work..

[eksg]

It not just the rendering that I loved but also the design.Can you please tell me how are you planning to do the wall mosaic and that nice thing on the ceiling?what type of material are you putting,lighting, etch.Im really impressed with the overall composition.It looks so retro but contemporary.

[Ernest Burden III]

how are you planning to do the wall mosaic and that nice thing on the ceiling?

 

Ah, the interiors.

 

All of your comments go to the design, which is done by my client. I cannot take any credit for that. All I did was show it well. The materials are shiny metals in a number of tones arranged in a pattern of random rectangles. The rest of the space uses either dark mirrors of black fabric. Lighting will be low, probably small spots but only enough to get away with claiming there is any light at all. Dark space.

[Ernest Burden III]

My finals for the exterior high-rise I posted my prelim of:

 

 

 

 

 

I pulled back the 3D-space color from what was in the prelim, but its still there and pretty strong still. I like the way the color paints up the client's towers.

 

I rendered these with C4D but did the GI pass with FinalRender-St2.

[eksg]

Thanks for that.

 

I would like to ask for some pointers on how i can adopt this method in 3ds MAX,if its ok to share your technique.its just sometimes that i get bored on looking at my renders,and most of the time due to my real nature of work as a contractor,i dont have time to go on the details.this always lead to clients being confused on what it really looks like.but if i tried to make it in a watercolor effect,they would appreciate the presentation and wont be asking some stupid questions(pardon me on that).i tried to make a watercolor effect using photoshop on my previous renders,but its not very convinsing.ived attached the original render and the edited one,i hope you could comment on it.thanks.

[Ernest Burden III]

I would like to ask for some pointers on how i can adopt this method in 3ds MAX,if its ok to share your technique.

 

 

You are asking a more general question than I'm dealing with in this thread. Adding linework is one way to bring your work away from strict realism, but I'm talking about using color in 3D space to push attention or mood. This can be used with photo-real work if applied with subtlety and no-one will notice, but you may find they respond better to the work because of it.

[Ernest Burden III]

Having a little time off between projects, I wanted to show the effect by animating it. I put the 3D-space color at 100% and turned everything else off. It exaggerates the point, but notice how you can tell the form a little just by the changes in color.

 

The cars have their own 3D color effect which I left on but mixed with the global effect. Given more time it might be good to alter the position or scale of color shapes on different buildings which would provide a break at the groundplane, for exapmle. I just didn't have time to tweek anything.

 

Pass one is just the colors, pass two turns on reflections on glass to add a hint of realism.

 

 

http://www.oreally.com/temp/3Dcolor.mov

[Brian Cassil]

Old thread I know, but just watched your little .mov. Pretty cool. By coincidence I recently started coloring z-depth and other channels to try and color tweak my images in more interesting and cohesive ways. Although I've been using monochome schemes to try and bring harmony to everything.

[Ernest Burden III]

I recently started coloring z-depth and other channels to try and color tweak my images in more interesting and cohesive ways.

 

Would you post some images? I'd love see how others are applying color or tone in 3D space.

[Brian Cassil]

Would you post some images? I'd love see how others are applying color or tone in 3D space.

 

Next image I do I will.

[Guest mercy]

The visuals are indeed great and I simply love it don't know how much time it took you do it.