2
$\begingroup$

I am attempting to make a red dot sight that is (relatively) physically-correct, but I would like to add a bloom/glare effect to the red dot. Basically, a face that emits red light reflects off a lens back to the camera, and the emitting face is not visible at all. Is there an easy way that I can filter out only that reflection and add glare to it in the compositor?

(diagram from Wikipedia):

enter image description here

$\endgroup$
1
$\begingroup$

You basically need to have some way to get only the reflection so that you can perform some effect on it (e.g., glare or blurring the reflection and adding it to the image). You could use color keying if you can't see anything else that is red, you could map an object to the screen of the red dot that was on a different layer only used for compositing, and you can also provide access to the glossy reflections in the compositor. Actually, all three techniques can be used to do this in a more universal manner, but depending on your situation, you will have to make the best choice.

Here is an example I just made:

  1. Enable glossy direct in render layers

enter image description here

  1. My compositor node setup (could be much improved...I just blur the bright parts of the reflection)

enter image description here

  1. Result

enter image description here

Blend file:

$\endgroup$
  • $\begingroup$ Grabbing the Indirect glossy pass and applying the glare on that worked for me. Thanks! $\endgroup$ – AlbinoPanther Apr 24 '18 at 2:09

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.