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Noise grain in my Max Normal Bake

polycounter lvl 12
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alexk polycounter lvl 12
It's been a while since I baked a normal map in Max, so I'm not sure what's going on here. I'm baking just a normal map from a highpoly and my output file looks like it has a noise filter applied. Anyone know how to get rid of that? It also shows up in my diffuse base. I'm only going off of memory for the settings in projection and renderer setups

bakingproblem01.jpg

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  • Mark Dygert
    Toggle on or off Global Super Sampling?

    You might want to straighten out those edges...
  • alexk
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    alexk polycounter lvl 12
    Thanks Mark... gave it a shot but still giving me that noise :( ugh, frustrating!
  • PixelGoat
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    PixelGoat polycounter lvl 12
    Having this problem aswell since a few weeks back... highly annoying, haven´t found a solution to it yet. If I send the exact same scene to a colleague and have him bake it, it comes out fine...
  • [HP]
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    [HP] polycounter lvl 13
    What version you guys using?
  • Ace-Angel
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    Ace-Angel polycounter lvl 12
    If it's happening in the diffuse, are you rendering with Mental Ray? Also, did you try merging the files in a new scene?
  • ShadowFox
    Found I was having issues when using Mental ray to bake the normal map, switched to scanline sorted it out.
  • EarthQuake
    You might want to straighten out those edges...

    The edges are there most likely because of triangle distortion on the uvs, straightening the image content would be counter productive. So no, don't straighten those lines, as it will break the look on the model. =)

    Relax the uvs maybe.
  • Mark Dygert
    It really depends on the model, but there are some areas on that normal map that will disappear and leave pretty bad seams if it gets down res'ed. He's barely getting enough pixels together as it is and it's probably 4x larger than it should be...

    It's easier to maintain a straight line of pixels than it is an aliased diagonal line. The line on the left side and the top could be straightened with very little effect to the final result.

    Typically if you're baking a little UV distortion on your low is fine because the distortion is compensated for when the material is baked. Again I would need to know more about the model to say for certain if this is a good course of action, but typically when baking it can be better to favor a straight line rather than an angled aliased line, especially when your sheet is 4x too big.

    On second thought, the speckle might be the format that he's saving it as, maybe its a compressed format? He should try outputting TGA's or some other lossless format and see if it still shows up.
  • EarthQuake
    The circular type shape he's using would likely be a bad candidate for clamping the edges down, too much distortion. A better solution to the mipping etc issue would be to simply have nice fat bevels in the high that would read well even when sized down.

    But that wasn't really my point, the point I was making is that you should not go around straightening up edges because they look weird in the normal map, the edges there are exactly how they should be to match the mesh/uvs. Even if that isn't what you were suggesting, it could easily have been read as such, and there is enough bad type "oh just paint it out in photoshop" advice floating around polycount already.
  • Mark Dygert
    I totally agree and I should of been more clear about which edges to straighten and why. I was talking about straightening the UV edges so it bakes straighter lines instead of painting straight lines. It might be a bad idea to straighten every line, but straightening the left side and the top edge shouldn't be much of an issue.

    Any idiot who's tried painting straight lines on a distorted map knows painting a distortion free image on a distorted image is next to pointless when trying to counteract distortion.

    Which is why I brought up the whole if you straighten the UV's, the stretching gets compensated for (to some degree) by the bake, which is what the person painting the straight line can't do without a high degree of difficulty..

    I'll use the example of a belt around a fat organic character the belt mesh isn't straight and if you relax it and leave it all loosey goosey it will baked aliased lines all over the place (like above), but if you square off the UV's you get crisp lines. Of course introducing too much stretching on the wrong kinds of shapes can thwart the positive effects of straightening a few lines but that's where experience, trail and error come into play.
  • EarthQuake
    Yeah absolutely, doing minor straightening(ie: where its not going to cause any/much distortion) is also a really good way to save UV space, often when you do a straight up relax on a shape that is slightly tapered, you'll get this weird curve shape instead of a nice rectangle, clamping your edges down can be a great wait to maximize space.
  • r_fletch_r
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    r_fletch_r polycounter lvl 9
    are you rendering as compressed TGA? i get this noise when im using TGA.
  • cupsster
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    cupsster polycounter lvl 11
    The tragedy is that max uses TGA as by default.. Having same issue, can't find solution yet. Sorry for bringing this out of grave.
  • cw
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    cw polycounter lvl 17
    in the rendering section of the preferences there is a dithering section - worth a look? Mine has both tickboxes ticked on 2011 64bit and I don't get these shenanigans happening.
  • cupsster
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    cupsster polycounter lvl 11
    Yeah I got that checked. Both of them. Can issue be that I use as source maps Jpegs? I'm just re-baking for unique unwrap with shadows. Doing same for source normal maps as well for diffuse. Is there any workaround I could use to transfer original diffuse to merged mesh with lighting?

    My main problem is that there is color noise in both diffuse and normal re-bake in 3DS Max. I pulled half of my hairs already. Deadline is in 5 hours for me.
  • Bad Spleen
    Have you attempted the bake on a different PC? It could be a problem with your PC setup, rather than an issue with your baking process.
  • Mark Dygert
    When was the last time you updated your video card drivers? What kind of video card do you have? Have you tried baking in scanline, mental ray or Vray? What about baking in xNormal?

    In general I would say try to stick to TGA it is an uncompressed format while working.
    Using a compressed format like jpeg will lead to a loss of quality because it is being compressed. I'm not sure a jpeg would cause noise (without looking at it and possibly running some tests myself) but in general most engines compress whatever you feed them so you really don't want to feed a compressed image to an engine that is going to compress it again. Which is why a lot of pipelines rely on TGA's.

    They might be large, slightly annoying to work with and might even slow down some slower video cards, but they offer the best chance of getting your work through the process as unmolested as possible.
  • EarthQuake
    Just as a general note: To deal with precision issues of 8bit file formats and the often extremely subtle information that needs to be stored in a normal map, you basically have two options:
    A. Noise or "dithering" which is what Max does by default
    B. Stepping, which is what Maya does by default.

    I personally prefer Max's dithering, but in practical use neither will really show up once your mesh is fully textured.

    Not sure if the noise people are getting in max is from dithering, or if its a file format specific thing. I've always used TGA in Max, Maya and most game engines use TGA as well, I've never noticed an excessive amount of noise from TGAs.

    Color noise in your diffuse bakes seems like there may be a deeper problem though. You could try saving out your maps as 16bit per channel(tiff?), which should negate any bit depth issues.
  • cupsster
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    cupsster polycounter lvl 11
    OK guys thank you all for reply. I figured it out. Problem of that colored noise which looked like mosaic filter in photoshop was that scene that was passed to me had materials which were glossy so it picked up a lot of color from nearby geometry. Same apply for normalmap re-bake. Standard color bleeding.
    To address texture formats, I personally using TIFF/PSD whenever I can cause I got thumbs and it can store layers. As for source files that I obtained in loosy formats, these weren't mine product so I must go with them. (Need to educate our 3D graphics a bit tho ;) ) I never use loosy formats for any graphic work! :) I'm using mainly Unity on daily basis so for me exit format is either PSD [for ease of adjustment] or mentioned TIFF.

    Thank you again dear polycounters! Great community.
  • lloyd
    r_fletch_r wrote: »
    are you rendering as compressed TGA? i get this noise when im using TGA.


    OH MY DAYS, I've had this issue for YEARS and just left it as I couldn't fix it.

    Tried again today and came across this thread. THANK YOU!

    Saved it as a png and all the noise went away, you notice it more if you start overlaying normals over themselves.
  • Neox
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    Neox veteran polycounter
    why are you compressing your tga?
  • Eric Chadwick
    TGA uses lossless RLE compression, so it's a good idea to use it IMHO, as it saves hard drive space. Sometimes I've had tools that don't support RLE, but that's rare.
  • marul
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    marul polycounter lvl 7
    I ran across a similar issue, and couldn't get rid of the grain no matter what I tried. After reading this thread I tried switching TGA bit depth from 16 to 24 and that solved my problem.
  • Eric Chadwick
    Ah, yes.

    16bit TGA refers to 16 BPP (bits per pixel) which means you only get 65,536 colors. This can cause banding, noise, etc. because there aren't enough colors to represent fine gradations, like in a normal map.

    24 bpp means you get 16 million colors, so it's better at avoiding banding, but still not quite the best. Normal maps have fine gradations of color, and rely on each pixel storing an exact value, so the map can recreate vectors for precise lighting.

    Programs like nDo, dDo, Handplane, etc. prefer working in 16 BPC (bits per channel) which means you get 281.5 trillion colors. No noise, no banding!
  • Eric Chadwick
    Just checked what they tell you in the 3ds Max save dialogs. Yuck.

    For the best results, and as long as you're going out to tools that support 16 bpc color (dDo, nDo, Photoshop, Handplane, etc.), I'd suggest saving in TIF format. The save dialog offers "8-bit Color" which means 8 bits per channel (bpc) which also means 24 bits per pixel (bpp) or 16 million colors. I'd choose "16-bit Color" which is your 16 bpc, 281 trillion colors.

    3ds Max's TGA plugin only supports 16 or 24 bpp. When it says 32 bpp, that just means you can save an alpha channel too. But it's still just 16 million colors.

    Hope that makes sense.
  • ElleKitty
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    ElleKitty polycounter lvl 3
    Highly agreed with Eric here; just save as TIFF. Set 8bit or 16bit, then compress with packbits.

    If you are saving from Photoshop, use TIFF instead of PSD; TIFF can hold everything that PSD can, and I do mean everything, even things like "smart objects" which seem like a PSD-specific feature. It compresses losslessly to about half the size. In addition to that, when you use TIFF, you can finally set the texture "Alpha Source" to "Image Alpha".

    When saving TIFF in Photoshop, use these settings for max compression that 3ds Max can still read.
    SaveTIFF.png?dl=1
    Make sure to also include layers.
    And of course, if there is any transparency in your image, the savebox will un-grey as well.
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