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Im getting this weird halo in my reflection when rendering. Does anyone have any suggestions to help with the node setup I have going on here for reflections to help get rid of this.

Top is showing the halo effect, bottom half has the node setup for the reflection

It was recommended to me that I have my mix shader at 0.5, but if I do that this happens I imagine due to the environment lighting:

enter image description here

So I guess where I am at now is is there a way to get the reflection of only the object which I have on a separate render layer, and not get the reflection of the environment lighting.

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  • $\begingroup$ maybe you could try using 'multiple importance samples' for your lights as for the node setup I suggest you put the mix value to 0.5 (0 is original image, 1 is second image only) $\endgroup$ – Yvain Mar 26 '16 at 20:01
  • $\begingroup$ Made an update to the original question. $\endgroup$ – CSSmitty Mar 26 '16 at 21:02
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    $\begingroup$ Without looking at your file is hard to figure out what kind of elements you are dealing with and how they are laid out. Can you upload your file? you can use blend-exchange.giantcowfilms.com and edit the resulting link into your question. $\endgroup$ – cegaton Mar 26 '16 at 21:39
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Activate the Clamp Checkbox in your Mix node. This should solve the problem.

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    $\begingroup$ Could you also say why it solves the problem? Your answer helps solving this particular problem but it would be good to know why it solves it for future problems. $\endgroup$ – palkonimo Apr 24 '17 at 21:01
  • $\begingroup$ Yes ofc. Sorry that I didn't give an explanation, but I was concerned it might look confusing while some might overlook the actual solution. As we all know, digital colors are represented by the three values R, G and B where the minimum is 0 and the maximum is 255. If you mix two images, these values has to be somehow processed. "Somehow" means, you can actually choose how. There are different ways. Some are based on pure mathematical algorithms (add, multiply, substract e.g.), while others are discribed by their visual behaviour (soften, harden etc.). They are called "blend-modes". $\endgroup$ – Monchichi69 Apr 26 '17 at 10:40
  • $\begingroup$ However - as we can only have 256 values for each channel, it can happen, that some opperation can't be done precisely as there are no float numbers. To solve this problem some programs are using values from 0 to 1 instead. Where 1 stands for 100% (256). All other values will be floats (0.x) then. But if you now add lets say two valules of 0.6 each, it becomes 1.2, which can not be represented by the normal RGB values. $\endgroup$ – Monchichi69 Apr 26 '17 at 10:41
  • $\begingroup$ So what the program then does, is up to the user. If you need the color-behaviour (surface-color), you can do two things: either just cut everhing above 1 or recalc all the other values, to make it right percentage-wise. None of the results will be the correct result of the actual operation (addition), but both prevent you from getting strange behaviour - just like the halos mentioned in this thread. But if you wanna use the value lets say for microdisplacement, values above 1.0 can come handy! Therefore you have the option to choose either to "clamp" or ... not. :-D $\endgroup$ – Monchichi69 Apr 26 '17 at 10:41
  • $\begingroup$ If my explanation sounds complicated or wrong - its just because of the explanation itself. Im not good in this. But I hope it helps anyways. $\endgroup$ – Monchichi69 Apr 26 '17 at 10:42

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