1. Open a new document, the size of ur choice ( black background) 2. Use the Line Tool (U) and while holding shift draw a 15 px (or the size u want) WHITE line. 3.Rasterize layer. 4. Duplicate the layer 3 times. 5. CTRL+CLICK on one of the layer then go to Select > Modify > Contract > 2 pixel ( more if ur line is bigger ). Then Create a new layer, name it "light" and fill the selection with white. 6.On the first layer (probably named Shape 1) go to Filter>Blur>Gaussian Blur> radius 20 to 30 ( i used 20 for the 15px line). 7. Select the second layer (probably named Shape 1 Copy) and pres CTRL+F. 8. Select the third layer (probably named Shape 1 Copy 2) and go to Filter > Blur > Gaussian Blur > Radius 5 to 10 ( i used 5) 9.Select the fourth layer Select the second layer (probably named Shape 1 Copy 3) nd go to Filter > Blur > Gaussian Blur > Radius 2 to 4 ( i used 2) 10. Merge down ur four blured layers ( Shape 1, Shape 1 copy, Shape 1 copy 2, Shape 1 copy 3) and name it saber. 11. Now there's several ways to color ur lightsaber, ill show u the one that i like the most. First way : Duplicate the layer named saber. On one of the two "saber" layer Go to the Blending options by double clicking on ur layer. Go to Color Overlay and choose the color u want. On the other one press CTRL+U and check the "COLORIZE" box. Lower the luminosity ( about -57) and, according to the color u chose in color overlay, put the good Saturation/Hue. Then put the blending mode to "OVERLAY". 12. Now on your layer named "light" go to Filter > Blur > Blur more and repeat it 'till it looks great or Filter > Blur >Gaussian Blur > Radius 1 or so depending on the size of ur layer. 13. to make it more realistic you can erase the corner of the white line. Final Result (you can also look at my Star Wars Render, I made all the lightsabers with this technique):
Yep, look at my star wars render, i did the lightsabers with that technique. Maybe tweaked up a little bit but, i tried with this tut and it looks pretty cool.
