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I have an object that emits light and I would like to apply the in-build modifier for a sine curve to create blinking lights in my object. However I can't figure out a way to not just work with the primary 3 colours (RBG) but a mix of those to create a unique shade. (I worked based on this tutorial: https://www.youtube.com/watch?v=FXaoXcJJquo) When I replace the keyframe with my chosen colourshade and then apply the modifier it does it automatically on red (first in list). Since the other 2 colours have their values but not the sine curve, my object blinks in different shades. If I then apply the same modifier settings to the other 2 colours, it goes through the blinking but only in grey/white and black. is there a way to join the colours or fix them somehow to then apply the sine curve modifier? or any other suggestions how I can let the object emit light once and then stay on (blink once)? but I'd like it to emit slowly and not like an on-switch. Thank you for any help!

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In the additive RGB color model you create different colors by adding different intensities of the primary colors red, green and blue together.

If you maintain some ratio of red, green and blue but change their values you'll generally end up with darker and lighter shades of the same “color”. The ratio R:G:B = 1:1:1 – i.e. the same value for red, green and blue – is noteworthy as it creates shades of grey.

However, if you also change the ratio of the primary colors then you will end up with different hues.

Let's say you want to create an LED which blinks by cycling from black to some bright orange tone and back to black. For the color orange let's use the RGB ratio of 2:1:0 [1]. This means you need no blue and twice as much red as you have green. If you use sine wave modifiers you have to set amplitude and value offset accordingly.

orange f-curve orange led

When the ratio of the primary colors is changed, e.g. by using a different phase offset for each primary color, you'll receive a LED which cycles between different hues.

cycle f-curve cycle led

Edit:
In situations in which you're only interested in single color LEDs, LEDs which cycle between two colors or LEDs which cycle in a set of predefined colors it's worth to consider animating the Emission Strength, the Mix Factor of a MixRGB node and/or the Factor of a ColorRamp node instead of working with three modifiers for the RGB components. This will minimize the work should you later decide to change the color of your LED.

mix, color ramp

[1] Color values, except for colors entered in the Hex field, are not gamma corrected. Entering an RGB value of 1, 0.5, 0 in Blender will not result in RGB values of 1, 0.5, 0 (or 255, 128, 0) in the final image.

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  • $\begingroup$ Thank you so much! I think I got it to work. will also try out the nodes, but not proficient at it yet! $\endgroup$ – cr1618 Feb 17 '17 at 10:02

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