I'm getting frustrated trying to render out AO maps from 3ds max 2010 to be used in texturing. The quality of my renders are not what i'd expect.Some areas are too dark, details not clear enough, unwanted shadows...

I do have some over-lapped parts but those I can live with and edit.

I've tried using both light tracer and mental ray methods, making sure the backgrounds and such are white, model asigned white material and setting sampling qualities to 128 etc... Takes me about 30 mins to render them out.

I'm trying to achieve a ao map that looks similar to this:
http://i259.photobucket.com/albums/h.../AOExample.jpg

But I end up getting something that looks more like this:
http://i259.photobucket.com/albums/h...ba91873/AO.jpg


I want a nice clean crisp ao with more white color and less darkened areas with details more defined.
Been using these sites as guides to give you some background info:
http://www.eddybrown.co.uk/blog/baki...ent-occlusion/

http://synthesisgraphics.com/tutorials/occlusion.htm

I watched the 3d motive tut on texturing military vehicles and the ao texture came from that.The tut is pro and should check it out.

Some of my problems might be coming from smoothing groups. That can be fixed.

Any help in improving the ao method is appreciated. I dont want to use high and low poly model bake method. Just want a nice ao from a model already made.

There is so much bad info on the internet btw.

Have you tried any of the methods at http://wiki.polycount.com/AmbientOcc...Baking_Methods ?

Maybe you can post your model too? It could just be that your high poly model isn't up to par.

If you are getting unwanted shadows you may have to set your trace depth so it doesnt send rays out into infinity. Not sure though.. haven't baked AO with 3ds.

If you aren't' exploding your models and taking the time to make a proper bake cage, then don't be surprised when you get wonky results. Trust me, it's time well invested. Better yet, don't trust me. Trust the Wiki and every decent tutorial on baking out there.

-deleted-

Originally Posted by cryrid

Have you tried any of the methods at http://wiki.polycount.com/AmbientOcc...Baking_Methods ?

Yes I've seen those methods. I cant post the model as that would be ill advised.Its not mine and this is personal work and learning for me.

I dont want to bake from high poly to low poly models as that would invlove me making a high poly model for each bake and thats just not practical if I want to use the ao's as textures for 100s of models.....

When you guys mentoin exploding the model, are you saying for me to split the model along the elements or objects ? I was under the impression the mesh should be attached into 1 object ? Thats what i've been doing.And rendering all objects attached into 1.

BTW this is suppose to be tank models. Not boxes found in most tutorials...Almost every tutorial sucks on the internet and is designed to give speed results more then doing quality work.

Originally Posted by Bubba91873

I dont want to bake from high poly to low poly models as that would invlove me making a high poly model for each bake and thats just not practical if I want to use the ao's as textures for 100s of models.....

Then your pretty much stuck with what your getting. AO maps aren't magic, they are totally dependant on the mesh they are baked from. You're only option is to make a highpoly or start painting the detail by hand.

Would Mudbox be a better alternative for the workflow that I want to achieve ? Is the ao bake better in mudbox ?

The model itself is pretty good quality and I cant imagine that its cuasing the poor render.I'm taking care to hide/delete parts and move over lapped uv's as needed.The rest i'll edit in photoshop.

There isn't anything wrong with the quality of the ao, its the quality of the art content. As others have suggested, a proper highpoly model to bake down is the best solution, doing AO from just a lowpoly model is always going to give you poor results, this has nothing to do with "how good" max bakes AO or anything like that however.

Originally Posted by Bubba91873

Would Mudbox be a better alternative for the workflow that I want to achieve ? Is the ao bake better in mudbox ?

The model itself is pretty good quality and I cant imagine that its cuasing the poor render.I'm taking care to hide/delete parts and move over lapped uv's as needed.The rest i'll edit in photoshop.

Describe precisely what exactly you think is wrong with the render.

Originally Posted by r_fletch_r

Describe precisely what exactly you think is wrong with the render.

Too many dark areas and shadows are being baked by all the methods that I've tried.And theres been alot....

The dark areas are covering up too many details out of my ao renders.Areas that should be lighter are not, and i dont know how to increase that with just the skylight in scene and the mental ray setups im using.

If I were to use these as a layer in photoshop set to multiply, it would seriously mess up the base layer that I would use to start the texture process.Places would be too dark with not enough detail brought forth.

In the dvd that i mentioned from 3dmotive, I suspect the instructor used Mudbox to render out cleaner ao's with perhaps some editing in ps.

it wont matter if you use max, maya, mudbox, or xnormal, your going it get the same results.

your either going to have to do a high poly and a exploded bake or spend time trying to docter it in photoshop.

and i wouldnt say all tuts are meant for speedy results i found some good articles on a ton of stuff including AO and normal bakes in the wiki here.

AO is a mathematical operation, occluded areas are going to be darker, completely occluded areas will be black. If your problem is just that areas are "too dark" you can simply decrease the opacity of your AO layer.

When we talk "quality" of AO, generally, you're refering to noise or other artifacts that can be reduced by more ray bounces, or more anti-aliasing. Anything else is related to your specific asset, not how good/bad X app renders AO.

The biggest difference between the "good" example AO you posted, and your "bad" ao, is the source content of the model, that model has a accurate highpoly model used for AO, with fine details etc modeled in. Other than that, the broader AO forms(which is all you'll ever get with a lowpoly model alone) look the same.

it wont matter if you use max, maya, mudbox, or xnormal, your going it get the same results.

Well, if he's a using skylight method, other programs would offer an alternative. Softimage's AO baking doesn't rely on lights, and I think xnormal is in the same boat. You'd be able to control the bias/gain/spread distance as well to be able to tweak the results more as well to limit where the occlusion appears, if he thinks it is coming out too dark. Geometry is still heavily important though, as are UVs (no overlaps, etc)

Originally Posted by cryrid

Well, if he's a using skylight method, other programs would offer an alternative. Softimage's AO baking doesn't rely on lights, and I think xnormal is in the same boat. You'd be able to control the bias/gain/spread distance as well to be able to tweak the results more as well to limit where the occlusion appears, if he thinks it is coming out too dark. Geometry is still heavily important though, as are UVs (no overlaps, etc)

Yes, various apps will offer a little control, and slightly difference results, however his basic issue is just fundamental, expecting his AO to offer him something that isn't actually there, and never will be without an accurate highpoly render to bake from.

What you're suggesting, and what he seems to be looking for, is akin to someone saying they suck at drawing, and wanting to know if switching from a pen to a pencil will make them better at drawing.

OP: Modeling high resolution models for the purpose of baking normals and AO is standard industry practice, its best to just embrace it as soon as you can, instead of trying to hide from it.

Yeah, that's what I was trying to get at with the geometry bit. I should have elaborated more.

Originally Posted by cryrid

Yeah, that's what I was trying to get at with the geometry bit. I should have elaborated more.

Yes I totally agree with what you said there, sorry if that came off as a bit snippy towards you, it was meant for the OP more than anything. =P

Originally Posted by cryrid

Well, if he's a using skylight method, other programs would offer an alternative. Softimage's AO baking doesn't rely on lights, and I think xnormal is in the same boat. You'd be able to control the bias/gain/spread distance as well to be able to tweak the results more as well to limit where the occlusion appears, if he thinks it is coming out too dark. Geometry is still heavily important though, as are UVs (no overlaps, etc)

Yeah exactly.
Like I said the mesh itself is quality and I can move the uv's off to the side in the uvw window.But results are same.

I thought since there was so many talented people here that there could be alternatives that most people dont know about, that would ease my workflow and produce results.

Plus, it seems that I can also edit the ao maps in Mudbox as needed with just paint brush along with the bake settings.Seems to be a much easier process then what 3ds max offers.

I thought since there was so many talented people here that there could be alternatives that most people dont know about, that would ease my workflow and produce results.

You cant expect something for nothing. Blaming Max is plain retarded.


It you want to reduce the broad dark areas then use MR AO with a low distance setting.

Originally Posted by r_fletch_r

It you want to reduce the broad dark areas then use MR AO with a low distance setting.

Yes I know about this setting. I've changed the infinate number 0 to 7.0m and tried at 100m.In my orinigal example pic I had it at infinate 0.

7 Meters!!!
If your tank is modelled to scale then the distance should be about about 10cm

AO is shadow based on proximity. If you dont want the ground to shadow the bottom of the tank then you reduce the distance so that its shorter than the distance between the bottom and the ground.

Originally Posted by Bubba91873

I thought since there was so many talented people here that there could be alternatives that most people dont know about, that would ease my workflow and produce results.

dude!

Way to take a crap on the rim and put the seat back down on top of it.

There ARE helpful people offering solutions that maybe you should think about.

But you seem confident enough to know what your talking about so, have at it and show us your new and improoved results with mudbox, maybe you'll teach us how to improove our workflows......

Originally Posted by r_fletch_r

7 Meters!!!
If your tank is modelled to scale then the distance should be about about 10cm

AO is shadow based on proximity. If you dont want the ground to shadow the bottom of the tank then you reduce the distance so that its shorter than the distance between the bottom and the ground.

I was just fooling around with the distance settings to see if there was a difference, 7m and 100m are just expeirments in the distance.

The model is too scale, so if i'm understanding you correctly, the distance I should set that value to is the meaurement of the tank itself or the measurment from the ground up to the bottom of the vehicle ?

From my understanding all objects in the scene affect the ao render and "could" ? cast the shadows or dark areas I'm seeing.

I've also tried baking them seperately and as 1 object attached.

Beleive me, I am listening to everyone and trying new things. But I will not produce high poly models just to bake ao's. I dont want to waste the next 100 years doing that.

Originally Posted by Hazardous

dude!

Way to take a crap on the rim and put the seat back down on top of it.

There ARE helpful people offering solutions that maybe you should think about.

But you seem confident enough to know what your talking about so, have at it and show us your new and improoved results with mudbox, maybe you'll teach us how to improove our workflows......

I'm listening and being polite.If I knew the answers I wouldnt be here.