[Texturing] – Balancing light on a texture plus sharpening the texture
Let’s say we have this texture metal taken from CGtextures website:
It is possible to perceive the difference of light across the texture and that becomes even more noticeable when an Offset filter is applied:
There are at least two options to remove or attenuate this difference of brightness.
1st technique – Average/High Pass to remove highlights
- Open the texture in Photoshop and duplicate the layer. Rename the layer to Average.
- Apply the Average filter to this layer. Filter>Blur>Average
- Duplicate the initial layer again and rename it to Linear Light 50%
- Place this layer on top of the Average layer
- Change the Blending mode to Linear Light and reduce the opacity to 50%
- To the Linear Light 50% layer apply the High Pass filter. Filter>Other>High Pass…
- For this image a radius of 100% worked quite well, but each texture will require a different radius. A useful tip is starting with the maximum radius and going down until the highlights aren’t noticeable.
2nd technique – Gaussian/High Pass to remove highlights
- Open the texture in Photoshop and duplicate the layer. Rename the layer to Gaussian.
- Apply the Gaussian filter to this layer. Filter>Blur>Gaussian
- With the Gaussian filter we want to keep some detail of the image
- Duplicate the initial layer again and rename it to High Pass
- Place this layer on top of the Gaussian layer
- Before applying the High Pass to this layer change the blending mode to Luminosity
- To the High Pass layer apply the High Pass filter. Filter>Other>High Pass…
- It is the same principle that we used on the previous technique. Tweak the radius until the highlights are removed.
In both techniques, it may be necessary some colour adjustment to return to the original colour.
3rd technique – High Pass to sharpening images
- Open the texture in Photoshop and duplicate the layer
- On the duplicated layer change the blending mode to Vivid Light and set the Opacity to 50%. This value of 50% is not mandatory and it will depend on the texture. You can use a value of 100% if needed.
- Apply the High Pass filter to this layer and tweak the radius to something around 0.8 to 1.5 Pixels. The main goal here is to get the very fine detail.
- Here is a comparison at 100% view:
- The image without the sharpening:
- And with the sharpening technique applied:
Let me know if you find this useful.