Creating car light trails using "Stroke path with brush"

[victor93rs]

Hi! I want to create some car light trails for a matte painting scene.

I'm using a "Stroke path with brush", applying Shape Dynamics so the brush size is reduced as it approaches the vanishing point of the scene (1st image).

However, when I use a Round Blunt tip (to produce a more realistic effect simulating the light trails of several cars, 2nd image), I'm not able to apply Shape Dynamics for the brush size (3rd image).

Do you know any other brush tip that could produce a realistic effect (such as in the 4th image), while also being able to reduce its size via Shape Dynamics?

Or what any other way could I achieve a similar result?

Thank you!

 

[agentmoeller]

I would use a solid, thin stroke (100% opacity and 100% hardness) and continue to use the "Stroke path with brush" function. Once you have a stroke, try adding an outer-glow layer style and playing with the settings, and then use a soft, low-opacity eraser to make the lines "disappear" as the red lines do in the bottom photo. (or better yet, erase them away with a layer mask and a black paint brush!!!) Since the lines are more or less parallel, you can get one just right, then copy it and adjust the settings slightly on subsequent lines.

 

[Rich54]

Here's a fairly easy three-step process:

1) Using the normal brush tool, create vertical red and white lines, all on them on one separate layer. Make the lines slightly narrower than what you want them to be when you're all done. If you like, apply a bevel & emboss to give them some dimensionality.



2) Select Edit>Transform>Perspective. Widen the bottom and narrow the top, as shown here.



3) Now apply the warp tool (Edit>Transform>Warp) to give the lines the appropriate curves. As an optional step, you can blur all or part of the lines to give it the desired effect.

 

[victor93rs]

I would use a solid, thin stroke (100% opacity and 100% hardness) and continue to use the "Stroke path with brush" function. Once you have a stroke, try adding an outer-glow layer style and playing with the settings, and then use a soft, low-opacity eraser to make the lines "disappear" as the red lines do in the bottom photo. (or better yet, erase them away with a layer mask and a black paint brush!!!) Since the lines are more or less parallel, you can get one just right, then copy it and adjust the settings slightly on subsequent lines.

Thanks agentmoeller and Rich54!

agentmoeller's procedure was the best way to achieve a realistic result. I ended copying and pasting a path like 15 times, and using the Pen Tool to move the vertex points to produce perspective-correct light trails. Also, I was greatly benefited by using the Warp command.


After having the paths ready, I used "Stroke Path with Brush", with different Brush diameters. Then, I reduced the stroke paths' layer opacity and applied some Outer Glow to the Layer Style.


Here you can see how it looks now, thanks for your help!

 

[agentmoeller]

Looks awesome. Glad we could help.