ZBrushCentral

BPR - How to get desired effect (deep AO/Shadows)

ZBrush Usage Questions
#1

High. I’m having trouble getting the effect I would like out of BPR. I am creating a lot of filters trying to push down the dark end of the AO and Shadows in order to get black in places such as the nostrils. This looks great in your standard “Best” render, but in a BPR render it seems to be rendering it with a lot of diffuse light.

When I push on these blacks really hard I get undesirable effects such as black all around the characters face.

Is there a base AO setting that I need to fiddle with? one that brings the detection in closer so it sees small cavities as having more AO? In the end i would like deep darks in areas such as deep in the nostrils etc…

Thanks

#2

If it’s a matter of the shading in the cavities not being dark enough, you can control the intensity of shadows and AO on the mesh on a material basis, in the Material>Environment panel, for shadows or AO respectively. Materials are at a value of 50 by default.

If that makes the AO then TOO present, you can choke back on it a bit (retreat the shading towards the cavities) by decreasing the angle slightly.

I’ve not had any luck making broad adjustments to the L and V depth sliders…very far in either direction results in garbage. But slight negative adjustments on the L-Depth, a couple points, no more, can also choke back the shading a bit.

If it’s a matter of AO not getting into the cavities you want it in at all, I have no easy answer for that. If you figure it out, let me know. Increasing the Rez in the BPR AO panel seems to result in better accuracy for Ao. I try to turn down the blurring slightly. You may have to bring in supplemental effects like cavity shading on materials to really get nitty gritty detail shading.

Just remember, though, most of this stuff is easily fixed in photoshop with render passes, so don’t drive yourself too nuts (like I did).

#3

Quick reply.

Yes, this is to do a 360 spin though. So i have some stills that are hand fixed which is awesome. But right now i’m doing a turntable.

Thanks man.

I’ll look into all that.

Right now i’m havingt a really had time getting it to even spin around where i want. I put a sphere as the base subtool and it still keeps spinning around behind the head. Its hard to get it to move its pivot!

#4

It should rotate around the mathematical center of the main subtool. But, you can run into weirdness with tools that have undergone offset in the worldspace sometimes, and been split off into their own tools. Deformation>Unify would fix that, but that might not be desirous. Sometimes there can be a problem with errant geometry.

In any event, its easy to fix. Just hide all but a couple polygons along the center of the model, or wherever you want it to rotate for the movie, and select Transform>Set Pivot. It should then rotate around that pivot for the purpose of your turntable. Select C.Pivot afterwards to clear it. Make sure to select the appropriate axis in the turntable options as well.

[edit] er, I’m actually in over my head, here. I’ve got the same problem with one of my tools where all the subtools are offset as a result of where they were created in relation to the original base tool. All the methods for setting pivot (S.Pivot, The Tool>Preview window, Unify) only seem to work on a subtool basis, and offset that subtool in relation to the others. So if you’ve got multiple subtools, and dont have the option to Merge them, at least temporarily to run one of these actions on all at once, I’m afraid I dont know how to fix that.

Sends up a flare for Marcus

#5

um… honestly this is pissing me the F* off. Its just not worth my time. It refuses to leave the center of the world and rotate around the sphere i have set at base subtool. even after exporting and reimporting it. and S.Pivot machinations and everything.

#6

Do you have the ability to merge any subtools into a single tool, at least temporarily for the purpose of the turntable? If so, any of those procedures should fix it …deform>Unify, set Pivot, dragging the center in the Tool> Preview window. It’s the subtools that complicate my situation. I can get it to rotate where I want for the turntable for any given subtool, but not the entire tool.

Otherwise, hopefully someone smarter will notice your issue. It’s simply outside my experience. You might try making a separate thread dedicated to this specific problem, though, since you started this as another topic that some people may have avoided for not knowing about the subject.

#7

Movie turntable rotation is about the world space origin. To change how your model rotates you need to change the position of all your subtools in world space. Here’s how you can do it:

  1. Turn on Ghost transparency and set the Draw>Axis slider to a high value so you can clearly see the axes.
  2. Select the main subtool or the subtool that you want centered on the origin. Make sure all subtools are visible.
  3. For the Tool>Deformation>Offset slider set the axis you want to use.
  4. Make one adjustment using the Tool>Deformation>Offset slider. It’s imperative that you only make one adjustment. You can adjust the slider up and down to position the subtool but don’t make any further adjustments after releasing the mouse.
  5. Press Tool>Deformation>Repeat To Other [at the bottom of the menu]. This will apply the action to all the other subtools. (Note: if you undo then all subtools, including the selected one, will be returned to their previous position.)
  6. Repeat 4 & 5 until you have positioned your model where you want.

HTH,

#8

Repeat to Other, eh?

I swear, Ive never even seen that before. How long has that been there?

(Thx, Marcus!)

#9

:slight_smile:

Since 4R2:
Additional Functions and Changes / Tool>Deformation>Repeat to Other