How to Convert an Image to PBR Textures: A Step-by-Step Guide

This tutorial will show you how to capture photos for texture creation, including how to set up your camera, how to calibrate colors, and how to post process raw images. Note that it includes two alternative steps for calibrating an image’s color: Step 2a is more for enthusiasts using tools that everyone has at home, and Step 2b is more for professionals.

Step 1: Choosing an Image

Choosing a good image to turn into a texture might seem to be an easy process; however, it can be tricky, and there are a few things to keep in mind.

First, you need to find an image that you can make seamless, without visible tiling. This means finding surfaces that are consistent in terms of color and structure, and that maintain a good balance between being appealing and being repetitive. It’s important to avoid surfaces with distinct focal points that will draw attention after the texture is created. For instance, when capturing images of walls, remember to check the part of the wall that meets the floor — usually it has some dirt and wear and is a darker color, and this could make things tricky in postproduction. I’d suggest going for a part of the wall that’s a bit off the ground.

The best way to capture a photo for a texture is to keep the camera parallel to the surface you’re capturing, because this will give you undistorted data. Try to look for the spots where you can put your camera in front of the surface. This is pretty easy when it comes to walls, but it can be a bit tricky when you’re photographing roofs or the ground from above, so in those cases I suggest using a drone. You can also try a long monopod and remote controller for your camera shutter.

This tutorial will focus on using natural light, because that gives the best results with minimal effort. However, when you’re using natural light, you have to consider weather conditions. The best weather for capturing any data for postproduction is a cloudy day, because it provides the most neutral lighting conditions, without hard shadows and overexposed areas. I always try to plan my shoots for cloudy days. This isn’t always possible; however, there’s a workaround. Instead of waiting for cloudy weather, you can wait for a moment when the surface you want to photograph is all in shadow. This does work, but you need to capture more light with your camera, so a tripod will sometimes be necessary.

Step 2a: Color Correction for Enthusiasts

For the simpler color-correction workflow, I’m going to use a picture taken with my smartphone camera — and the best camera is always the one that you have with you. If you’d rather follow the professional workflow, skip to Step 2b.

Image 1: Image of the chosen surface.

The photo above was taken with the Camera Raw option selected in my camera app.

We need to calibrate colors, so we’ll use a piece of white paper to set the image’s white balance.

We also need to download darktable; it’s a pretty powerful postproduction program, and it’s totally free.

1. When darktable is installed, we can import our images by adding them to the library (as shown in Image 2).

Image 2: The primary interface of darktable; Add To Library is at the top left of this window.

1. Double-click on your image to open it in the Darkroom.

Image 3: First steps in darktable.

1. We need to open the original version of our image; by default, darktable opens images with some built in presets, to make pictures look more vivid, but we need to use raw data to keep our image as close to the real world as possible.
2. Simply type “white balance” in the text field, and open the settings.
3. Use the detection tool and move the box to your pure white area.

Image 4: White balance calibration.

Now we need to adjust exposure, so just type in “exposure” and open those options.

1. Move the exposure slider.
2. Aim to get the curves more or less in the middle.

Image 5. Exposure adjustment.

Now your picture is calibrated, and you can skip the next section and go right to Step 3.

Step 2b: Color Correction for Professionals

For the professional color-correction workflow, we’re going to need a digital camera, preferably one with a high Mpix sensor. A lens in the 20mm–50mm range will do the job. For the best results, try to use prime lenses, because they are usually sharper. The amount of detail will have a major influence on the final result. We’ll also need a tripod and a color checker. I would recommend using the X-Rite color checker because it’s an industry standard, and many color correcting programs have a preset for it.

Image 6: Image of the chosen surface.

Here is a preview of a picture I took for this tutorial. It has a color checker in it. If you’d like to shoot something from close range, you can just shoot two pictures — one with the color checker and one without — and then you can calibrate the one with the color checker and copy and paste settings to the other image.

When we have everything ready at the location, we need to set up our camera. We’re concerned with three major settings: ISO, aperture, and shutter speed.

• ISO: I’m suggesting an ISO lower than 200 because we should try to capture images with as little noise as possible.
• Aperture: For photos taken from a distance, like the one above, you should use the aperture setting that will give you the sharpest image. Usually it’s something in the middle range, but you can just search online and check your lens specification. If you’re shooting closeups and the surface is very bumpy, try to consider depth of field. Sometimes the middle value is not enough, and some of the details that are far from the camera are already blurred. In such cases, just close your aperture a bit more. This will result in a wider depth of field, but it also affects the amount of light that hits the camera sensor, so tripod usage will be necessary for a longer exposure.
• Shutter speed: This is the setting we need to tweak every time, but it’s pretty easy. Just turn on curves in your camera settings, and tweak the value until your curves look like the ones in the image below. This means that your photo doesn't have any underexposed or overexposed areas.

Image 7: Camera settings.

When our picture is ready, it's time to upload our files and color correct them. I’m using the darktable application; it works pretty fast, it has all necessary options, and it’s free.

1. We’re uploading images and then adding them to the library (as shown in Image 8).
2. Then go to the Darkroom.

Image 8: The primary interface of darktable.

1. We need to open the original version of our image; by default, darktable opens images with some built in presets.

Image 9: Opening files in their original form.

1. Then we type “color calibration” in the bar on the right, and select Calibrate With A Color Checker.

Image 10: Choosing options from the menu bar.

1. We need to choose the color checker we used, and align it properly on our image.
2. Next, go through three options on the bottom right of the interface.

Image 11: Color calibration with the color checker.

1. Then we’ll open another menu for exposure.
2. And we’ll take values from it to correct exposure and black offset.

Image 12: Exposure calibration.

1. Finally, lens correction from metadata.

Image 13: Lens correction.

Step 3: Cropping the Image

And now we need to crop our image to be square. Sometimes we need to adjust rotation a bit to keep the pattern consistent.

Image 14: Cropping the image.

1. Then we export our image as a JPG or PNG file.

Image 15: The Export window.

And now our texture is ready to be used in Poly.

Step 4: Creating a PBR Material from an Image

1. We need to open Poly, choose Create A Texture, and select Upload Image.

Image 16: The Poly Create Texture tool.

1. When our image is uploaded, the next step is to make it seamless with Poly’s Make Seamless tool; sometimes, you’ll need to try a few times to get a perfect result. For this texture, I found that 100% and the prompt shown in the image below worked best.

Image 17: Poly’s Make Seamless tool.

1. Now we can see how our tiling looks.

Image 18: The Tiling viewport.

The final step is making a PBR material from our seamless texture; we’ll need to try different presets for different textures — for this one, choosing “Diverse” as PBR Material Type should work perfectly.

Image 19: The Finished PBR material.