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enter image description here

The actual rendered png shows nothing at this pixel(white circle), because alpha is 0.

But Render result window still has some color visible(white circle).You can see its alpha value as well in this picture above which indicate this pixel should be total transparent.

My color management setting are basically SRGB and Standard.

Is there a way making render result showing exact the same thing png does?

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  • $\begingroup$ if you don't want that question closed again, you should add a blend file so we can check it out. You nearly gave us any useful information what you did. And "normally" you should edit/improve your old question - not ask the same again. Duarte will love you for that... :D $\endgroup$
    – Chris
    May 16 at 8:33
  • $\begingroup$ @Chris A file will not save this question from closing... it's the same problem asked over and over again, why a saved png with transparency looks different than a full dynamic range render result. $\endgroup$ May 16 at 9:50
  • $\begingroup$ You are totally right. But a file will hopefully (including me) make people wanna help and answer this question and will make sure that it is the „right“ answer because we can test it. That’s what I like about blend files. And as you know as very experienced Blender user - there can nearly always be several reasons for most of the questions. $\endgroup$
    – Chris
    May 16 at 9:53
  • $\begingroup$ And of course I wanna „save“ people from the bad experience here that questions are closed before they got any answer - which I experienced myself a lot in my beginning here - which is very frustrating. $\endgroup$
    – Chris
    May 16 at 9:54

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Alpha channel is used differently in different types of software. Then you save this image in PNG, alpha will be converted from premultiplied to straight and this pixel will be transparent. It is an actual headache for newcomers, these are just a couple of questions:

Glare Transparency Correct in Render, but lost in save to PNG

EXR color difference to PNG

Why are transparent colours desaturated when exported?

How do I get the Glare node to output transparent instead of Black background

Glow effect invisible on transparent background

Straight Alpha

Method where RGBA channels are stored as (R, G, B, A) channels, with the RGB channels unaffected by the alpha channel. This is the alpha type used by paint programs such as Photoshop or Gimp, and used in common file formats like PNG, BMP or Targa. So, image textures or output for the web are usually straight alpha.

Premultiplied Alpha

Method where RGBA channels are stored as (R × A, G × A, B × A, A), with the alpha multiplied into the RGB channel.

This is the natural output of render engines, with the RGB channels representing the amount of light that comes toward the viewer, and alpha representing how much of the light from the background is blocked. The OpenEXR file format uses this alpha type. So, intermediate files for rendering and compositing are often stored as premultiplied alpha.

Info from blender manual

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