Introduction
Color matching is easier when your reference is visible directly on top of your render.
Instead of switching between windows, you can use PureRef as a small overlay above 3ds Max or the Corona VFB. This lets you compare your material color against the reference while you adjust it.
This workflow is simple, but very useful for archviz. It helps when you need to match wood tones, paint colors, fabrics, tiles, or any material where the color needs to be close to a reference image.
What PureRef Is Used For
PureRef is a lightweight reference board application.
In this workflow, it is used as an always-on-top image overlay. You place your reference image above your render, then adjust the material in 3ds Max and Corona Renderer until the color looks close.
Why This Helps
- You can compare the render and reference in real time.
- You do not need to constantly switch windows.
- You can sample colors directly from the reference.
- You can keep multiple reference images visible while working.
Tip: PureRef is not only useful for color matching. It is also helpful for collecting mood boards, material references, and design inspiration while working in 3ds Max.
Download and Install PureRef
Go to the PureRef website and download the version for your platform.
During the download process, you can choose to contribute to the development team. If you are only testing the software, you can enter a custom amount of 0.
After downloading, run the installer.
Installation Steps
- Accept the terms.
- Choose the destination folder.
- Select the components to install.
- Keep the default settings if you are not sure.
- Click Install.
- Run PureRef.
When PureRef opens, you will see a black rectangle on your screen. This is the empty PureRef canvas.
Basic PureRef Setup
Before using PureRef with 3ds Max, adjust a few simple settings.
Right-click the PureRef window and open Settings.
Turn Image Borders off.
This keeps the reference cleaner and removes unnecessary visual distractions around your images.
You can leave the other settings at their default values.
Keep PureRef Above 3ds Max
Right-click the PureRef window again.
Go to:
Mode → Always On Top
This is the most important setting for this workflow.
When Always On Top is enabled, PureRef stays visible above 3ds Max, Corona Renderer, and other applications, even when it is not selected.
Important: Without Always On Top, PureRef can disappear behind 3ds Max when you click back into your scene.
Moving the PureRef Window
PureRef uses a different navigation style than most applications.
To move the PureRef window:
- Press and hold right-click.
- Drag the window to the position you want.
This lets you place the reference directly beside or above the area you are matching in the render.
Add Reference Images
To add images to PureRef, simply drag and drop them into the PureRef window.
You can add one image or many images.
You can also run multiple PureRef windows if you want separate boards for different references.
Useful Examples
You could use separate PureRef windows for:
- Wall paint references
- Wood floor samples
- Fabric colors
- Tile references
- Furniture material references
For color matching, it is often best to keep the reference board small and focused. Too many images can make the comparison harder.
Move, Scale, and Rotate Images
After adding an image, select it first.
Then you can:
- Move it by pressing and holding left-click.
- Scale it using the blue dot on the edge of the image.
- Rotate it using the same control.
This is useful when you want to place the reference close to the rendered material or resize it so the comparison is easier.
Tip: Try to keep the reference image close to the area you are adjusting. Your eye can compare colors more accurately when they are near each other.
Useful PureRef Options
PureRef has many right-click options. You do not need to learn all of them immediately, but a few are useful for this workflow.
Right-click the PureRef window to access the main menu.
Window Options
The Window section includes tools for controlling the PureRef window itself.
Useful Window Tools
- Maximize
- Minimize
- Resize selected image
- Lock window
The Lock Window option is especially useful.
It prevents you from accidentally moving the PureRef window around. You can still move the images inside the window, but the window itself stays in place.
Tip: Lock the window once your reference is positioned over the render. This avoids accidentally dragging it while adjusting materials.
Image Options
The Image section contains tools for working with images inside the PureRef window.
Useful Image Tools
- Select all images
- Align left
- Align right
- Align top
- Align bottom
- Stack
- Normalize
The Normalize option can help match the size of selected images quickly.
You may not need it often, but it is useful when you have several reference images at different sizes and want them to feel more organized.
Use PureRef with 3ds Max and Corona Renderer
The main idea is simple:
Place your reference image in PureRef above your render, then adjust your material color while comparing both at the same time.
This works especially well with Corona Renderer because you can use the Corona color picker and interactive rendering while you make changes.
Use Region Render to Work Faster
Even if your computer is fast, it is a good idea to use region render while matching colors.
Instead of rendering the whole image, draw a region around the material you are adjusting.
Why Use Region Render?
- It updates faster.
- It focuses only on the material you are changing.
- It avoids wasting time rendering areas that do not matter.
- It makes color adjustments easier to judge.
For example, if you are matching a fabric color, render only the part of the sofa or chair where that material appears.
Pick a Sample Color from PureRef
With PureRef on top of your render, use the Corona improved color picker to sample a color from the reference image.
This gives you a quick starting point.
The first picked color may not be perfect in the render because lighting, reflections, and post-processing affect the final result. But it gives you a useful base to start from.
Good to know: A sampled color is only a starting point. You will usually need to adjust it after seeing it in the render.
Adjust the Material Color
In the example workflow, the material color is adjusted using a Corona Color map.
The color is refined with:
- Saturation
- Value
You can also use a Color Correction map or another color adjustment map if that fits your material setup better.
The goal is not only to match the flat color sample. The goal is to make the material look close to the reference inside your actual lighting and render setup.
Compare and Adjust in Small Steps
Color matching usually takes several small adjustments.
A practical workflow looks like this:
- Place the PureRef reference near the render region.
- Sample a color from the reference.
- Apply it to the material.
- Render a small region.
- Adjust saturation and value.
- Compare again.
- Repeat until the color feels close.
Small changes are safer than large changes.
If you push saturation or value too far, the material can quickly become unrealistic.
Match Colors After Lighting Is Close to Final
This is one of the most important parts of the workflow.
Try to match colors only after your lighting and post-processing are close to final.
If you change the lighting later, the material color may look different. Then you may need to repeat the color matching again.
Finish These First
Before final color matching, try to have these close to final:
- Main lighting direction
- Light intensity
- Camera exposure
- Post adjustments
- Overall render mood
Important: Do not spend too much time perfecting material colors before the lighting is established. Lighting changes can completely shift how colors appear.
Common Beginner Mistakes
Matching Too Early
If you match colors before the lighting is set, the result can change later.
Get the lighting and post adjustments close first, then refine the material color.
Comparing Images in Separate Windows
Switching between a reference image and the render makes color comparison harder.
Keep the reference visible with PureRef so your eye can compare both at the same time.
Rendering the Whole Image
Full-frame rendering is slower when you are only changing one material.
Use a region render around the area you are adjusting.
Expecting the Sampled Color to Be Final
A color picked from the reference may look different inside your scene.
Use it as a starting point, then adjust saturation and value while checking the render.
Practical Workflow Summary
PureRef Setup
- Install PureRef.
- Turn Image Borders off.
- Enable Always On Top.
- Drag and drop your reference images.
- Position the reference over or near your render.
3ds Max and Corona Workflow
- Use a region render for speed.
- Pick a sample color from PureRef with the Corona color picker.
- Adjust the material with a Corona Color map or color correction map.
- Refine saturation and value.
- Compare the result against the reference.
- Avoid final matching until lighting and post-processing are close.
Conclusion
PureRef is a simple tool, but it can make color matching in 3ds Max and Corona Renderer much easier.
By keeping your reference image directly above your render, you can judge colors faster and make better material decisions. Combined with region rendering and small color adjustments, it becomes a practical workflow for everyday archviz production.
Use it whenever you need to match materials to a reference image, especially when accuracy and consistency matter.
