How do I get rid of these spots in Iray Render?

dracorndracorn Posts: 1,814
edited January 1 in The Commons

What's causing these spots on the skin (most noticeable on the chest) and how do I get rid of them?

Marellian No red translucency Maps (Rylee).jpg
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Post edited by dracorn on

Comments

  • HanabiHanabi Posts: 344

    Render 2 times as large for half the time and scale down.

  • dragotxdragotx Posts: 669
    dracorn said:

    What's causing these spots on the skin (most noticeable on the chest) and how do I get rid of them?

    Make sure Draw Dome is enabled in your render settings, I've seen that before with a particular skin shader (doesnt' look like you're using that one, but it may be a related issue)

  • CatinBagCatinBag Posts: 35

    Since theres not that many of them, I think it might be faster to simply photoshop them out with a small healing brush.

    But rendering it again at higher res then scaling down will work too.

  • AlienRendersAlienRenders Posts: 609

    That may be the bug with SSS with certain colours. I've reported it. They still haven't fixed it as I just tried it again and it still does the same effect. You could try choosing a different colour for SSS colour or selecting mono. You could also try turning on draw dome, but not sure if that would affect the final render.

    Here's what it does with more extreme colours.

  • L'AdairL'Adair Posts: 5,112
    dragotx said:
    dracorn said:

    What's causing these spots on the skin (most noticeable on the chest) and how do I get rid of them?

    Make sure Draw Dome is enabled in your render settings, I've seen that before with a particular skin shader (doesnt' look like you're using that one, but it may be a related issue)

    I'm not sure what is the cause, (AlienRenders appears to, though,) but I do know what is happening. Those "spots" are actually transparent pixels. Whatever background the image is on is the color you'll see. And the longer you let the image render, the more of those "spots" you'll get. I recently figured out turning Draw Dome to On gets rid of those, as Dragotx mentioned above.

    A quick fix for images that you've already rendered is to render another copy of the scene with Draw Dome on, and then layer that image under the original in your graphics program. Because it won't be your final image, you don't have to render it for long, maybe 100 to 1000 iterations, (depending on your system, the size of the original image, how complex the image, etc.) And if the spots are concentrated in a single area, you can use the Spot Render tool, open Tool Settings and set the option to New Window, and just render the problem area, (with Draw Dome On, of course.)

    @AlienRenders, I hope Daz fixes the issue, and it's good to know what causes the problem. Draw Dome set to On doesn't work in situations where you want the transparency, and rendering twice, (my quick fix above,) shouldn't be necessary. But I admit, I now use Draw Dome On unless I need the background to be transparent.

  • dracorndracorn Posts: 1,814

    OK, I have turned Draw Dome on, and have a render cooking.  I'll let you know how it looks.

  • dracorndracorn Posts: 1,814

    It's working!  Thanks!

  • dragotxdragotx Posts: 669
    dracorn said:

    It's working!  Thanks!

    Awesome!  Glad we could help

  • dragotxdragotx Posts: 669
    L'Adair said:
    dragotx said:
    dracorn said:

    What's causing these spots on the skin (most noticeable on the chest) and how do I get rid of them?

    Make sure Draw Dome is enabled in your render settings, I've seen that before with a particular skin shader (doesnt' look like you're using that one, but it may be a related issue)

    I'm not sure what is the cause, (AlienRenders appears to, though,) but I do know what is happening. Those "spots" are actually transparent pixels. Whatever background the image is on is the color you'll see. And the longer you let the image render, the more of those "spots" you'll get. I recently figured out turning Draw Dome to On gets rid of those, as Dragotx mentioned above.

    A quick fix for images that you've already rendered is to render another copy of the scene with Draw Dome on, and then layer that image under the original in your graphics program. Because it won't be your final image, you don't have to render it for long, maybe 100 to 1000 iterations, (depending on your system, the size of the original image, how complex the image, etc.) And if the spots are concentrated in a single area, you can use the Spot Render tool, open Tool Settings and set the option to New Window, and just render the problem area, (with Draw Dome On, of course.)

    @AlienRenders, I hope Daz fixes the issue, and it's good to know what causes the problem. Draw Dome set to On doesn't work in situations where you want the transparency, and rendering twice, (my quick fix above,) shouldn't be necessary. But I admit, I now use Draw Dome On unless I need the background to be transparent.

    That's interesting to know if affects other things as well, I've only ever run into it using Echvo's pale skin shader for g8, but I still haven't gotten adventurous with trying new materials and such.

  • L'AdairL'Adair Posts: 5,112
    dragotx said:
    dracorn said:

    It's working!  Thanks!

    Awesome!  Glad we could help

    +1 yes

    dragotx said:

    That's interesting to know if affects other things as well, I've only ever run into it using Echvo's pale skin shader for g8, but I still haven't gotten adventurous with trying new materials and such.

    For 2017's Christmas Card, I rendered a room scene, then used it for the background of the window scene, which I rendered with transparency so the background image would show through the windows. I ended up having to rerender the window scene with Draw Dome on to fill in empty pixels on the nutcrackers. That's when I finally realized I needed Draw Dome to get rid of those. I still liked the original render better, so I used the second image under the original and used the outline of the original to mask the second render and let the room show through.

  • dragotxdragotx Posts: 669
    L'Adair said:
    dragotx said:
    dracorn said:

    It's working!  Thanks!

    Awesome!  Glad we could help

    +1 yes

    dragotx said:

    That's interesting to know if affects other things as well, I've only ever run into it using Echvo's pale skin shader for g8, but I still haven't gotten adventurous with trying new materials and such.

    For 2017's Christmas Card, I rendered a room scene, then used it for the background of the window scene, which I rendered with transparency so the background image would show through the windows. I ended up having to rerender the window scene with Draw Dome on to fill in empty pixels on the nutcrackers. That's when I finally realized I needed Draw Dome to get rid of those. I still liked the original render better, so I used the second image under the original and used the outline of the original to mask the second render and let the room show through.

    It came out loking good.  I'll have to keep that trick in mind, I've never even thought about doing something like that

  • L'AdairL'Adair Posts: 5,112

    Thank you, @dragotx. Spot renders work really well too, especially if your graphics program will automatically stack multiple images into one, like my old Photoshop CS6 does. I do my main render, and if there are any issues I didn't catch before hand, I can make the correction, do a spot render to new window, and when I'm ready, load them all up in PS with the original on the bottom layer. Sometimes I need to mask a layer and only allow specific parts to show up, other times it's just load and flatten. Either way, I love the spot render tool. So much easier than rerendering an entire image. to fix a bit of poke-though or the like.

  • dragotxdragotx Posts: 669
    L'Adair said:

    Thank you, @dragotx. Spot renders work really well too, especially if your graphics program will automatically stack multiple images into one, like my old Photoshop CS6 does. I do my main render, and if there are any issues I didn't catch before hand, I can make the correction, do a spot render to new window, and when I'm ready, load them all up in PS with the original on the bottom layer. Sometimes I need to mask a layer and only allow specific parts to show up, other times it's just load and flatten. Either way, I love the spot render tool. So much easier than rerendering an entire image. to fix a bit of poke-though or the like.

    I really need to try that, so far all I've used PS for is the clone/spot healing tools to fix minor pokethrough.  Anything that those two can't handle I wind up just leaving, or re-rendering the entire image

  • AllenArtAllenArt Posts: 2,780

    This is the main reason I don't like the chromatic SSS shader and go back to mono a lot of the time. I hope they can fix it. It's horrible.

    Laurie

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