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I've an image with this properties: plane properties How can I do so that it's slowing disappearing?

Thanks in advance

SteZano
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    I think that you can use principled bsdf instead of those nodes and use alpha value... you give alpha value 1, set keyframe and set another keyframe with value 0 to make it disappear over span of those keyframes – MikoCG Oct 22 '21 at 06:57
  • Hi I need this nodes for other reasons ( https://blender.stackexchange.com/questions/234516/blender-how-can-i-render-true-color ) – SteZano Oct 22 '21 at 07:56

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Just use a Maths node to manipulate the Alpha channel. You can either set it to Add or Subtract and ensure you have the Clamp checkbox enabled (so you don't get out of range) or you can use it as a Multiply and change the value of the multiplication between 1.0 (for 'normal' alpha) down to zero (for completely transparent).

nodes

Rich Sedman
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  • It works for me! thanks – SteZano Oct 24 '21 at 07:18
  • @SteZano Great - glad to be able to help. You can mark this answer as the 'Accepted' one by clicking the 'tick' just below the voting buttons on the left of the answer. This will help othersto find the solution. – Rich Sedman Oct 24 '21 at 08:14
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Can you see the difference between these 2 pictures? enter image description here

One uses your setup, one uses principled BSDF

My setup for it is this: enter image description here

You can then animate it using this value: enter image description here

0 is visible, 1 is invisible

MikoCG
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    ok, thanks I'll try. But how can I add the "subtract" chart? enter image description here – SteZano Oct 22 '21 at 13:07
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    It is called "Math" node, you can then select Substract in the menu that you can open above the "clamp" button – MikoCG Oct 22 '21 at 13:09
  • Lighting conditions can overbrighten the Principled. With even light it will not be very noticeable, especially when seperated; I dare you to feed both into a Shader to RGB, then Vector Subtract followed by Absolute. – sybog64 Oct 22 '21 at 15:19
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    I don't think this is absolutely right... using the Principled BSDF for pure emission you shouldn't connect to the Base Colour and should instead set it to pure black - otherwise you'll get a surface response from incident light rather than pure emission as described in the original question. – Rich Sedman Oct 22 '21 at 21:59
  • I try your option @MikoGC but with value = 1 the transparent background becomes black and the image grey (see https://i.stack.imgur.com/BjC0S.png) - am I somehow wrong? – SteZano Oct 24 '21 at 06:59