Weird results when baking textures in Blender Cycles, help!

[LisaMarie McWinnie]

Hello! I'm having an issue with baking materials in Blender Cycles. It only happens with certain materials, I'm not sure why. I'm using Blender 2.75, what am I doing wrong here?

This is my material setup:

 

 

 

 

 

 

This is how the model and material look in render view:

 

 

 

And finally, how it looks when I baked it at 500 samples (very similar to my 100 samples test):

 

 

 

 

[Drongle McMahon]

I don't know whether this will help. I am assuming your complaint is that the intense highlights of the rendered image do not appear in the baked texture. Depending on the details of the lighting, this may be predominantly a result of something that is often overlooked, that baking does no use a fixed camera position. In a rendered image, specular highlights are very dependent on the camera angle, as well as the incident lighting. When an image is baked, there is no camera, and so there is no fixed camera angle. Instead the lighting at each pixel is effectively rendered as if the camera was pointing along the normal at the coddesponding point in the mesh surface. Except in the rare case that that happens to coincide with the camera angle in the rendered view, this means that specular reflections will not match what you see in the rtendered image. So setting up the lighting and camera to give desired specular effects in the rendered view will not, in general, yield the desired highlighting in the baked image. I'm not sure there is a general solution to this problem. I guess you have to arrangle the lighting with this restraint in mind, in some way that I don't know.

[Chic Aeon]

I can't actually tell either what the issue is. The absence of shine or the black areas in the lace?  I have a big monitor and your photos are way too small for me to see and when enlarged just get blurry. So I can't actually tell much about your node set up.

I can verify that you CAN get lots and lots of shine in Cycles (and I never ever change the camera so have no idea what Drongle's message means LOL). I pretend the camera isn't even there.  You basically want an overall even lighting which in most cases for me included four equidistant lights and a sun.

 

 

 

This gets a nice bright shine inworld when needed with few cast shadows (which "I" try to avoid anyway). 

 

 

 

I will say that "lighting is everything" and so adjusting your lights might be the issue.  I can remember when I first started out that things looked SO good in render view and did NOT shine inworld. I am guessing that is your issue maybe.  It is also more difficult to get shine on "bumping" surfaces so if you have a  some displacement going on that might hamper your efforts.

 

 

If you can explain more and take some close ups of the area in BIG form (for me anyway) then we might be able to figure out the exact issue. 

[Drongle McMahon]

"...so have no idea what Drongle's message means LOL). I pretend the camera isn't even there."

Exactly. The camerat isn't anywhere. Or, it's actually at a different place fo each pixel in the bake. That's why the all-round lighting you describe works well to give you lot's of shininess - there's usually a light source in the right sort of place for most of the pixels. But, it will never give you the same distribution of shininess that you get with a render from a particular camera angle.

[Chic Aeon]

Ahhh. Well I found that out from trial and error I guess LOL.     

 

[Klytyna]

Ok, I'm seeing 3 classic mistakes here that apply across multiple rendering platforms over the last 10-15 years.

 

1. The "Use Ambient Occlusion" option is NOT an automatic no work involved add photo realism button.

2. People who make mistake 1 almost invariably leave the AO strength/opacity turned up way way to high, leading to the AO shadows being way way way too dark for for where they are and what lighing they are supposed to be in.

3. People who make mistakes 1 and 2 almost invariably leave the AO range way way too large, leading to the too dark shadows spreading too far, leaving you with that "she carried a bucket of spilled ink in a fold of her dress" look.

 

AO systems frequently default to the idea that you are a pro 3d artist who knows how it all works, doing architectual previz renders of new office buildings in a virtual summer afternoon in Death Valley, so you want really dense shadows between the building and the sports car parked a yard away.

 

*IF* you were going to use AO on that dress in that lighting, you'd want max occlusion range set to 1/2 an inch or LESS, and strength/opacity down to maybe 5 or 10% of current values, and then use a much higher sample rate so its not all spots.

 

For specular, your time would be better spent baking a grey scale 'spec map, with a decent contrast spread for the fabric pattern, say min average rgb for the pits between the fabric threads 96, fabric thread highlights 128, fancy embroidery 160, which you could then usze as a spec map in the SL materials, and run thru a normal map filter to make a decent normal map for the SL materials,  Then you could add the maps, set the specular tightness to 60 or 70, set a white with a hint of dress blue specular color and have a satin sheen effect for those with advanced lighting turned on.

[Chic Aeon]

Just wondering if you are talking about CYCLES render here as that was the OP's issue. I have to admit I have no idea what you are saying LOL (nothing new really) but it sounds more like Blender Render to me. I have never changed anything you describe from the defaults in cycles and have no issues. 

 

Just trying to clarify for the thread. .

[Chic Aeon]

While looking through my Google Stream for a tutorial I found this recent photo. It is wonderfully glossy and shiny in world. So wanted you to know that it is possible and that lighting should help some.

 

 

IF you want MORE shine than that I would suggest lowering your glossy node close to the 0 range. If you go TOO far though you end up with just black and white with no "grays" for the filter and that won't work at all. So a fine line there. Also less displacement. 

[Klytyna]

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Chic Aeon wrote:

Just wondering if you are talking about CYCLES render here as that was the OP's issue. I have to admit I have no idea what you are saying LOL (nothing new really) but it sounds more like Blender Render to me. I have never changed anything you describe from the defaults in cycles and have no issues. 

 

Just trying to clarify for the thread.

.

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Ok... Look at the two pictures of the dress posted by the OP...

 

The nice looking on is a static render of the dress with cool lighting etc.

 

The nasty looking one, see the area where the cloth over the 18th c hiproll, dips back down towards the side of the corset? See the dense black gritty shadows? That is 'Ambient Occlusion, it's a digital render trick designed to simulate the effect of objects in close proximity blocking each others share of ambient lighting (thats where light bounces off the walls, floor, furniture , curtains, your cat etc before hitting an object, as opposed to direct lighting which comes straight from a light source), and in the OP's case it is turned up way way way too high.

 

As for not knowing about "Materials", "specular and normal maps" or "Advanced lighting" in the context of texturing mesh in SL, if you are a content creator, you need to search the wiki and learn.

[Chic Aeon]

So  you are suggesting that she turned her Ambient Occlusion up higher than the default?  It will be interesting to see if that is the case. I think that better lighting would have solved the issue  -- if indeed that is one of the issues the OP was about (that is still unclear as we haven't heard back.

 

And I will respectfully disagree on the normal and specular maps to deal with the problem. There is a big percentage of resisdents that cannot use Advanced Lighting or choose not too. The whole point of Cycles rendering is to give a semi-realistic look of shine and shadow (I choose to keep mine in the subtle range most often) WITHOUT the need of specular and normal maps --- which of course are also more trips out to the server and more download rendering needed.   

 

So getting the look she wants without the normal and specular maps would in my mind be a much better plan. Again, just an opinion. 

[LisaMarie McWinnie]

Thanks a lot of the feedback guys. I actually had Ambient Oclussion turned off, but I'm testing with it turned on, see how it looks like.

I'm adding a better picture of my node setup, don't forget to click on it to see it in its full size.