How to improve your 3D render: Quick post processing in 5 simple steps

The art of 3D rendering provides the ability to make images look larger than life. You have total control over the look and feel of your image. You can take ages to tweak the look to your desire. But you do not always have the time to go all out. That is why in this article I want to share some secrets from my own workflow. I will share how I go from my initial base 3D render and edit this 3D render in Photoshop, to quickly make my renders pop.

My workflow exists out of 5 basic steps. I will quickly explain what I do and how I do things in each step. My renders originate from Keyshot, and my editing is done in Photoshop. So let’s get started.

1. Correct Base Image

The first thing is to start with the correct form for the base image. What I mean with this is to make sure that your base render does not have over blown highlights or underexposed shadows. It is important to take this in consideration and get this correct from the beginning. For example I use Keyshot and often when I save one of my images I will save it in a Low contrast photographic color setting. Instead of the Basic color settings. This isn’t always necessary. But in the cases when it is necessary, this will provide me the option to properly color correct my image without worsening over blown highlights that were there from the beginning.

A sort of equivalent of this aspect for film editors is to shoot in a Log color format. Or with rendering, to render in a 32 bit color space for even more color control (I won’t be covering these topics more in depth in this article, but I do suggest to look more into this yourself).

So below is the base 3D render I start with. It is straight out of Keyshot:

Base 3D render – Low Contrast Photographic color space

2. Color correcting with Camera Raw

So the next step would be to color correct the image. What this means is to properly distribute the colors form blackest blacks (the shadows), to whitest whites (the highlights), and all the colors in-between. The way I do this is by using the Camera Raw filter in Photoshop. You can find this at Filter>Camera Raw Filter. I would normally just click on the Auto option to automatically let the Camera Raw Filter distribute the colors. If I do not like the result, I would jump in to change some of the values of the Camera Raw Filter to my liking. For example change the Exposure, Contrast, Vibrance etc. But like I said, 99 out of a 100 times, using the auto function is more than enough for a quick edit.

Below you can see the comparison between the base 3D render (before) and applying the Camera Raw Filter (after).

3. Increase Contrast

Using the Curves Adjustment Layer

So the next thing I like to do is increase the tonal contrast of the whole image. I do this to make the colors pop even more. There are several ways to do this. A basic way to do this in Photoshop is with the Curves Adjustment Layer. Which you can find at the bottom of the Layer panel. Under The Create Adjustment Layers button. And ever so slightly editing the curves adjustment layers curve into an S-shape. So as to increase contrast between shadows and highlights like this:

What the curves adjustment layer basically is, is the following: On the x-axis you have the color space distribution from the image itself. Left being black/dark colors, to right being white/bright colors. On the y-axis you also have this distribution. but by picking a point on the line in the graph you can move the point up and brightening the colors from the x-axis, or moving the point down and darkening the colors from the x-axis. So selecting a point to the left (dark colors in the image) and moving that point down on the y-axis, darkens the dark colors in the image. Vice versa, selecting a point on the far right on the x-axis, and moving that point up, brightens the bright colors in the images. Thus increasing the contrast.

Below you can see the comparison between the Camera Raw Filter edited image, and adding the Curves Adjustment Layer over it.

Using NIK Collection: Color Efex Pro – Tonal Contrast

Another option that I like to use is with a third party plugin called NIK collection. And then specifically the Tonal contrast filter in their Color Efex Pro tool. I know that not everybody will have access to this. It used to be a free plugin collection. But nowadays if you didn’t already have it before, you will need to pay for it. That is why I also shared the first option using the Curves Adjustment Layer.

But using the NIK Collection’s Color Efex Pro tool, I like to use the Tonal contrast filter with the following settings: Highlight 25%, Midtones 50%, Shadows 25%, Saturation 20%. This filter makes the contrasting colors just pop a little better. Sometimes it even pops things too much. In that case I will just turn the opacity of the layer down to my liking.

Below you can see the comparison between the Camera Raw Filter edited image and The Tonal Contrast edited one.

4. Sharpen

So with the previous steps all the color correcting and color grading is done. The next thing I like to do is add a sharpening layer over the image. But the way I do this, is with a neat little Photoshop trick that goes as follows:

Step 1: Copy your Camera Raw edited layer and drag this layer to the top.

Step 2: Turn the copied layer into grayscale. Easiest way to do this is with the hotkey Ctrl+Shift+U

Step 3: Go to Filter>Other>High Pass and put in a value of 2,0 for the Radius. If you then press enter you get a picture looking something like this:

High Pass Filtered Grayscale Image

Step 4: Now change the blending mode of this layer to Overlay. This will create a sharpening layer. Sometimes it even sharpens things to much. In that case I will just decrease the layer’s opacity to my liking.

Below you can see a comparison of the Tonal Contrasted image with and without the sharpening layer over it. The change is just ever so subtle (for high resolution images, and better quality images than images in a browser window, the differences will become way more apparent).

5. Ambient Occlusion

The final thing I like to add is an Ambient Occlusion Pass. If you would like to know more about Ambient Occlusion and how to make an Ambient Occlusion Pass in Keyshot, I suggest you have a look at my previous post about Ambient Occlusion here. Or have a look at the Ambient Occlusion chapter from my Keyshot for Beginners course on YouTube here. For now you can see the Ambient Occlusion Pass I created in Keyshot down below.

Ambient Occlusion Pass

I take this Ambient Occlusion Pass and put it at the top of all the layers. Then I set its blending mode to Mutiply. You can see the added effect in the comparison below. In this case I turned down the opacity of the Ambient Occlusion layer to 50%. To make the effect more subtle.

Final Result Comparison

So those are the 5 simple steps I take, to make my 3D renders look even better. Below you can see the before and after between the starting 3D render and the fully edited one. A night and day difference if you ask me.

And for your information: If you would like to see a more thorough post processing workflow. I recommend you to have a look at the below YouTube video from my Keyshot for beginners course. In it I explain all the below steps and more, to create a stunning final edit for a 3D render.

If you have any questions or remarks, you can always leave a comment below.

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