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Simplest way to create specular map

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danshewan polycounter lvl 8
Hey guys,

So there seems to be a myriad of ways to create a specular map, but I'm wondering what the simplest way is, inside Photoshop. I wasn't planning on creating it from the normal map - I thought the simplest way to generate the spec map would be to duplicate my Diffuse layer, and use an Adjustment layer to desaturate, then alter the brightness and contrast.

Is this right? Or is there a 'better', or more effective way of generating a specular map, without being overly complicated? I'm not much of a Photoshop ninja, so I'm trying to keep it simple. I guess I'm more of a Photoshop nightwatchman right now.

Thanks in advance.

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  • MoP
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    MoP polycounter lvl 18
    I tend to work on all my maps at once.

    If you think that the method of creating a specular map is to copy it from a "finished" diffuse map and tweak it, then you're probably wasting a lot of time - since the way specular can affect the look of diffuse really means you should work on both at the same time (along with gloss, normal and whatever else you're displaying on your model).

    So for example each "material type" (eg. wood, metal1, metal2, rubber, plastic, glass, whatever breaks down nicely in a structure) I will have one "base layer" with a layer mask, and all related layers to tweak that are in a clipping mask above the base layer.

    This means that I can ctrl+click on the layer mask to select it, and easily apply it to other layers - so once you've set up the "base materials" for your diffuse, you can copy the whole diffuse group and tweak the base levels before going on to add detail.

    It also sounds like you're thinking about it wrongly, you don't just want to copy the diffuse, desaturate it then tweak the levels/brightness/contrast - that won't necessarily get the results you need for something to look good. You may need to apply totally different colours, even more saturation, or sometimes completely different layers to get certain effects.

    That's just what I reckon anyway.
  • AlanSMitchell
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    AlanSMitchell polycounter lvl 14
    thats how I do it
    "simplest way to generate the spec map would be to duplicate my Diffuse layer, and use an Adjustment layer to desaturate, then alter the levels and then colorize it and give it a color of some type my fav is a dark blue. I also see people use dark blue on faces of characters.
  • AlanSMitchell
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    AlanSMitchell polycounter lvl 14
    my post just got pwned
  • Peris
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    Peris polycounter lvl 17
    desaturate diffuse, play a bit with levels and then sharpen it a few times!!
    //runs away
  • Rick Stirling
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    Rick Stirling polycounter lvl 18
    Taking a desaturated diffuse and slapping it on the model is NOT the way to go, but most people do start that way.

    If you are stating from a diffuse map then try the Filter> Other> Highpass rather that a straight desaturate.

    I've had success with desaturating a normal map and then selectively darkening areas of it.
  • danshewan
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    danshewan polycounter lvl 8
    Thanks for the reply, MoP.

    I'm not surprised that my approach is flawed - I'm still so new to texturing, I suspected I might be approaching it incorrectly, and one of my biggest concerns is either misinterpreting the intended use of various maps, but also of developing bad habits from the outset.

    I'd certainly appreciate any pointers to resources explaining the do's and don't of specular mapping, or anything else I should be reading.

    Thanks again.
  • shadows
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    shadows polycounter lvl 18
    You can use the diffuse and simply play with the levels in certain cases, but adding extra info in the specular that the diffuse doesn't have, will give you better results.

    An example would be shiny wood with a varnish finish on it.
    You'd never use the diffuse as the base for the specular or if you did, it would be barely visible. What you would have in this case as the specular, would be a texture that has a rather even color across it and with some darker tones/splotches to show the wear and tear.

    There isn't a simple way of doing the specular because the way you do it will vary depending on what the material is made of and how it reacts to light.

    What Id suggest though if you're not already doing it, is to work in a single "master" psd file and use groups to separate the diffuse, specular, normal etc maps.
    This way it is much easier to work on both textures at the same time, since you don't have to copy your diffuse over to the specular psd every time you make some changes to it.
  • danshewan
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    danshewan polycounter lvl 8
    Taking a desaturated diffuse and slapping it on the model is NOT the way to go, but most people do start that way.

    If you are stating from a diffuse map then try the Filter> Other> Highpass rather that a straight desaturate.

    I've had success with desaturating a normal map and then selectively darkening areas of it.

    Thanks for the input, Rick. Since my original approach is definitely not the way forward, and you mentioned that many people do start out that way, is there a reason for this? Seems like a good way to learn bad habits.

    Is it possible (or advisable, if it is) to render out a specular map using Max's RTT? So far I've only really rendered out AO, height, normal and diffuse maps.

    Thanks for the tips, guys. Keep 'em coming.
  • danshewan
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    danshewan polycounter lvl 8
    shadows wrote: »
    What Id suggest though if you're not already doing it, is to work in a single "master" psd file and use groups to separate the diffuse, specular, normal etc maps.
    This way it is much easier to work on both textures at the same time, since you don't have to copy your diffuse over to the specular psd every time you make some changes to it.

    Okay, so since it is possible to render out the specular from RTT in Max, I'm presuming that this is the way to proceed? Oh, and yeah, thanks shadows - I am using groups for the various maps within a single PSD, but I didn't render out a specular map yet.

    Thanks again for everyone's input and patience with a tiring beginner. :)
  • Ruz
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    Ruz polycount lvl 666
    well i just erm desaturate the diffuse then muck about with it a fair bit, often painting in to it.

    I don't think it matters long as you get what you are after.
  • shadows
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    shadows polycounter lvl 18
    Is it possible (or advisable, if it is) to render out a specular map using Max's RTT? So far I've only really rendered out AO, height, normal and diffuse maps.
    For skin some people like to do that as base or to have an overlay. But for props or other objects , I don't really see why you'd want to that , since it will affect how the light reacts with the surface. You usually don't want to have directional info from lights in your textures.

    But like what Ruz said only the end results matters, so if it looks good to you and your client/peers think it looks good too, then that's what matters.

    The first time I did a specular map for a character, I spent hours trying different approaches until I found something that was looking good to me. So just experiment, look at assets from other games. Like the assets from the UDK and those should give you good examples.
  • danshewan
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    danshewan polycounter lvl 8
    shadows wrote: »
    For skin some people like to do that as base or to have an overlay. But for props or other objects , I don't really see why you'd want to that , since it will affect how the light reacts with the surface. You usually don't want to have directional info from lights in your textures.

    Well, not wanting directional light information from the scene baked into a texture makes sense, but I have to admit to being a little confused - if I shouldn't render it out from the scene file in Max, or be desaturating the Diffuse layer in Photoshop, how should I be generating the specular map?

    I understand that the exact approach will vary depending on the material and the scene into which it needs to fit, but I'm more concerned primarily with actually generating the map to begin with, and less so with adjusting it to achieve suitable results.

    Thanks for the continued input, everyone.
  • shadows
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    shadows polycounter lvl 18
    Well you don't "generate" a specular map, you do it the same way you do the diffuse map. You paint it or use photos or a combination of both.
  • shadows
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    shadows polycounter lvl 18
    And if you want some extra help, from RTT. Just add a few lights to the scene and render out the completeMap or DiffuseMap. Or you can also use the red and green channel of the normal map too and experiment with those for overlays.
  • HAL
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    HAL polycounter lvl 13
    Well depends on the way which you used to create the diffuse.

    (at least thats the way I create my spec maps)

    I texture the diffuse in some 100-200 layer psd and use that psd as a base for the specular map in order to achive certain looks in it.
    By that I can adjust certain parts without effecting others and vise versa.

    Like shadows said, additional work in the diffuse gives it a certain bling bling that wont be there with just desaturating it.
    And with that method I for my part get quite good results...
    (and it works quick, too)

    And I agree with Ruz, too as long as it looks good...it should work out

    I dont know if the others agree with me here.
  • danshewan
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    danshewan polycounter lvl 8
    shadows wrote: »
    Well you don't "generate" a specular map, you do it the same way you do the diffuse map. You paint it or use photos or a combination of both.

    Okay, this makes a lot more sense to me now. Thanks for the advice, everybody.
  • martinszeme
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    martinszeme polycounter lvl 8
    I pretty much use the same technique as MoP.
    I've found that using one big psd file is easier than to use 5 or even more files. Also remember to name and if it helps color code your layers and groups. And start naming at the start so when you duplicate your base layers for spec, opacity etc purposes than you have atleast the base name correct.

    Also I like to create "save to this file" actions so I don't have to go to File - Save As - choose the right file name for this layer (head.spec) etc and assign a hotkey to it (F2, F3 …). The only thing is that it kinda doesn't work if you start to work on different texture - it just saves your new texture over the old one and that can be annoying but after a while you get used to checking it.

    Maybe someone knows of a better solution for that?
  • MoP
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    MoP polycounter lvl 18
    martinszeme: Yeah, HarlequiN released Volition's "vTools" Photoshop scripts which can save out multiple groups to separate TGAs based on naming conventions.

    I've written a more lightweight streamlined similar thing for work but I still need to figure out if I can get permission to release it publicly.
  • martinszeme
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    martinszeme polycounter lvl 8
    Thanks Mop! Will definitely check them out. Any other workflow/file management improving scripts worth checking out?

    One more thing about spec. A lot of people create specular maps just black and white and adjust levels but I would strongly suggest against this. Reason is that it makes the surface look bland and most of the time not realistic (although sometimes that's what you need). For example skin benefits if the spec color is a bit blueish or I like to add a bit of color (subtle though) for metals so they have that heat damaged look.
    This is a good example: http://www.cpsculpture.com/art/kelpbracelet.jpg You can see some reds, orange, yellowish tones in the inside of that bracelet.
    Wooden surfaces I usually make almost monochromatic with a slight tint of diffuse color.

    Of course this doesn't apply for all situations. Just some of guidelines I wanted to share.
  • helldiver
    Well here's the method I use for mass producing spec maps. For single stuff that I want to show off or for portfolio work, or if it was for an FPS game, I'd take a longer time. But if I need to mass produce a bunch of them I use my quick method.

    Step 1: keep my diffuse in layers.
    Step 2: grab each layer, go to hue-saturation and set hue to -180, saturation to -65 (work with this on each layer to establish the best desaturation suitable for you).
    Step 3: grab each layer and do brightness-contrast to -41 for brightness and +68 for contrast. Again you might need to tweak those numbers depending on what you want.
    Step 4: you might need to clean up some stuff that incorrectly gets darkened when you want it to highlight (or vice versa), thats when I just use regular photoshop tools to fix it.

    That might not be the best method. I've played tons of games particularly MMOs. I rarely spend more than 2 seconds seeing if a peice of armor, a weapon, or scenery have the right highlights in the right spots, or if the grime is in the right spots.

    Oh forgot to add the general rules of what a specular map does (others with more experience can correct me or chime in).

    A) More of the same color saturates that color more. So if you have red in your diffuse and you keep it red in the specular it will be a very strong bleeding red. If you desaturate the red in your specular then it won't be so strong. Don't want to desaturate to grey, then grey will be pushing the red. I use the negative hue method instead.
    B) Lighter it is the more it shines, darker the less it shines. This is why you might need to edit some things by hand. Others do, but I rarely keep skin in layers.
    C) The combination of A and B and the values inbetween give you a good Spec map.
    D) Keeping the Diffuse in layers is very good because there might be a peice on there that is metallic, while the rest might be skin, plastic, or some other material. The values for metallic will be different than for skin. You want the skin to be nearly matte, whilst the metallic to have highlights.
  • eld
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    eld polycounter lvl 18
    copy diffuse, grab diffuselayers, adjust specmap!


    ps. dont forget the glossmap!
  • danshewan
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    danshewan polycounter lvl 8
    Thanks again for everybody's replies - it's always great to have so much input on a topic.
  • System
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    System admin
    That's the old school method for me too, flatten diffuse and save as spec, adjust levels etc.

    Now the psd's are kept in layers, once a good diffuse is made it's saved as a specular and then every individual layer is adjusted (levels, contrast, curves, blending modes and opacity) Most layers are desaturated except those which have a good variety of colour information or if they look cool.

    There's a few things to watch out for: say you have a layer mask your happy with in diffuse as an overlay/multiply and in the specular you want to give it more oomph and change the blending mode to linear light/vivid light this may reveal parts of the mask that you don't want which means more painting to get rid. So it's always advisable to keep the original format psd's with all the layers present so you can revisit the textures as required. When your finished flatten and save the psd's as targa's but still keep them somewhere safe, unflattened!

    MoP: recently I had 70+ layers in the diffuse, don't think I could juggle 140 at the same time, that would be a major headache :(
    EDIT: reworking the generator textures and the diffuse has 117 layers so far...
  • 3DRyan
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    3DRyan polycounter lvl 8
    I'll have to agree with dudealan's method. The specular map always seems to take the least bit of time for me with my models. Color or diffuse maps take the most.
  • eld
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    eld polycounter lvl 18
    yep, since usually you already did most of the work with the diffuse, meaning, you've placed the materials, dirt, ao, and you know what kind of specular and gloss values you have,

    creating the spec/glossmap is just a matter of setting the right values for what you've already done.
  • Anuxinamoon
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    Anuxinamoon polycounter lvl 14
    Usually as I work I have a Spec folder, which houses alot of Layer Adjustments in it with masks for specific areas. Its good because it updates as your diffuse updates when your polishing.

    But when the diffuse is done I spend a few good hours on tidying up the spec map, making sure the right areas are specular and never to overpowering.

    Spec is just as important so its good to get it looking right. A bad spec will ruin your model.
  • Smash
    helldiver wrote: »
    Well here's the method I use for mass producing spec maps. For single stuff that I want to show off or for portfolio work, or if it was for an FPS game, I'd take a longer time. But if I need to mass produce a bunch of them I use my quick method.

    Step 1: keep my diffuse in layers.
    Step 2: grab each layer, go to hue-saturation and set hue to -180, saturation to -65 (work with this on each layer to establish the best desaturation suitable for you).
    Step 3: grab each layer and do brightness-contrast to -41 for brightness and +68 for contrast. Again you might need to tweak those numbers depending on what you want.
    Step 4: you might need to clean up some stuff that incorrectly gets darkened when you want it to highlight (or vice versa), thats when I just use regular photoshop tools to fix it.

    That might not be the best method. I've played tons of games particularly MMOs. I rarely spend more than 2 seconds seeing if a peice of armor, a weapon, or scenery have the right highlights in the right spots, or if the grime is in the right spots.

    Oh forgot to add the general rules of what a specular map does (others with more experience can correct me or chime in).

    A) More of the same color saturates that color more. So if you have red in your diffuse and you keep it red in the specular it will be a very strong bleeding red. If you desaturate the red in your specular then it won't be so strong. Don't want to desaturate to grey, then grey will be pushing the red. I use the negative hue method instead.
    B) Lighter it is the more it shines, darker the less it shines. This is why you might need to edit some things by hand. Others do, but I rarely keep skin in layers.
    C) The combination of A and B and the values inbetween give you a good Spec map.
    D) Keeping the Diffuse in layers is very good because there might be a peice on there that is metallic, while the rest might be skin, plastic, or some other material. The values for metallic will be different than for skin. You want the skin to be nearly matte, whilst the metallic to have highlights.


    This reallllllllllly really helped me!

    Im a noob when it comes to spec/diffuse/normals e.g. but I was looking for a good explanation because I wasnt entirely sure how to get the look I wanted and this really helped me..
  • joebount
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    joebount polycounter lvl 12
    This should help a bunch of people understanding what to do with spec maps :
    http://www.manufato.com/?p=902
  • Parkar
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    Parkar polycounter lvl 18
    If you want to go for the real quick and dirty desaturate diffuse for spec you might as well just reuse the difuse and adjust it's values in the shader. This way you aren't wasting a texture sample and graphics memory on a texture that esentially contains the same information as the diffuse.
  • tyddynroger
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    tyddynroger polycounter lvl 6
    i came across this which was really helpful

    [ame="http://www.youtube.com/watch?v=5Gqp4bNJ52M"]Specular Map Creation Tutorial - YouTube[/ame]
  • Computron
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    Computron polycounter lvl 7
    That video is great because it shows some practical examples of spec map usage, as well as filters and tricks that where used to derive them. Cool, I wish there where more like that.
  • ScudzAlmighty
    awesome video, thanks for sharing
  • r_fletch_r
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    r_fletch_r polycounter lvl 9
    i came across this which was really helpful

    Specular Map Creation Tutorial - YouTube

    I wouldn't really agree with this being all that insightful(the first bit). Its just a couple of steps above desaturate the diffuse. Also no mention of a gloss map which is equally as important.

    Making a specular map is not something you do as an after thought, you need to structure your diffuse correctly so that you can use it to derive the specular.

    Its really important to break up your texture into material based layers/groups.

    for my last model I had a layer stack like this:

    [WEAR]
    -[Scratches]
    -[Dirt]

    [METAL]
    -[Copper] Dark Copper Colour (Reflective materials have low diffuse contributions)
    -[Steel] Dark Grey metal texture

    [WOOD]
    -[Chipped] A Lighter desaturated version of the wood. (find reference!!)
    -[Varnished] What ever wood I was using

    Each layer a full image with its coverage being controlled by a layer mask.

    Once I have the Diffuse pretty much complete I Duplicate it twice. 1 for spec and 1 for gloss.

    I then either colour correct the texture, replace it with a suitable noise pattern, or fill it with a flat colour.

    [WEAR]
    -[Scratches] - > On the metal I fill this with a bright tone, on the wood a dark one.
    -[Dirt] - > Dirt isn't generally reflective unless its wet so I darken this alot.

    [METAL]
    -[Copper] -> Bright Copper coloured texture.
    -[Steel] - > Bright Slightly colour tinted.

    [WOOD]
    -[Chipped] - Worn wood is quite rough and unreflective so this is dark.
    -[Varnished] - Varnish reflects alot to I made this quite bright.


    For the gloss you need to do some research on the material.
    Think of glossyness as how mirror like the surface is.

    so if you can see clear crisp reflections in a material the its gloss is white, as the reflection gets blurrier the gloss is darkened.

    heres the textures

    DIFFUSE
    deringer_diff.jpg
    SPEC
    deringer_spec.jpg
    GLOSS
    deringer_gloss.jpg


    and the result:
    deringer_low_2.jpg



    Its a good idea to bake an ambient occlusion map and a concavity map as they make great masks for placing dirt/wear
  • Shuriken UK
    I just tend to do somtehing like this in PS:-

    Making a black & white version of the group of layers that make my normal map, then modifying it to my "predicted needs"

    it usually works just fine, and because I keep all my layers seperate, I can always make whatever readjustments I need, since your working non-destructively. Even if I find myself "backed into a corner", I can just grab one of the layers from another map like the "norm or diff", then add it to my spec.

    Just keep everything seperate. Each PS file can end up pretty big sometimes when you have so many layers (I usually have atleast 5 layers for each map in any 1 material), but its a price worth paying IMO.

    I've not been doing this for very long though, its just a method I discovered was easy and simple enough to roll with in most cases. Theres probably a FAR better way of doing it, used by people that have got proper experience in the field.
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