I have written before about creating star spikes, or the star diffraction effect, but that method was not very reliable.

This new method produces a nice effect on your stars and is relatively easy to do using Photopea.com.

Result

Here is an image of NGC 3195 with three stars that have the diffraction effect applied to them:

The spikes on each star match the color of the star, which improves the image. The rest of the image is unchanged and only the stars involved in the effect have been affected.

Adding A Diffraction Effect or Star Spikes To Your Stars

Do the following:

  1. Make a backup of your original image
  2. Point your browser to Photopea.com
  3. From the menu, select File – Open and open the image to which you want to add the diffraction effect
  4. Long-click on the rectangular selection tool at the top-left of Photopea until the menu pops-out as shown:


  5. Select the Ellopse Select tool
  6. Press CTRL + Plus a couple of times to zoom into your image
  7. From the menu, select Window – Navigator to bring up the navigation window
  8. Navigate around your image using the navigator window (drag the red rectangle around), and find a star to which you want to add the diffraction effect, or star spike
  9. Click and drag from the upper-left to lower-right of the star to select just the star as shown:


  10. Press CTRL+C to copy the star, followed by CTRL+V to paste it (you’ll see a new layer in the Layers panel on the right side of the screen)
  11. Press and hold the CTRL key on your keyboard and click the checkered window next to Layer 1 on the right side of the screen, as shown:


  12. From the menu, select Edit – Free Transform
  13. Press and hold the ALT key on your keyboard and click and drag at the lower edge of the star so that the star stretches vertically, as shown:



    You want to stretch the star to the length you want the star spike to be. Pressing ALT causes your change to be symetrical in the upper and lower part of the star.
  14. Put your pointer over one of the markers on the edge of the box, press and hold ALT, and then drag to reduce the width as shown:



  15. Press Enter on your keyboard to commit the changes
  16. From the menu, select Select – Deselect
  17. From the menu, select Layer – Duplicate Layer
  18. From the menu, select Image – Transform – Rotate 90
  19. From the bottom right, where it says Normal, open the drop-down menu and select Screen as shown:



  20. Click the layer above the Background layer, as shown in the screenshot below:


  21. Where it says Normal, open the drop-down menu and select Screen
  22. From the menu, select Layer – Flatten Image

You have now created a star spike, or the diffraction effect.

Save your file by using the File menu, or export it to whatever format you like.

Conclusion

In this article, you learned how to create a star diffraction effect, or star spikes, using a reliable method. You learned about selections in Photopea and learned how to transform the selections, plus you learned about layers and how to edit them.