Saturday
Nov062010

Tutorial 12: How to create an Alpha Map for Sculpting in ZBrush/Sculptris

Sample displacement map generated automatically from 2 photos with Photosculpt TexturesHere is how you can create an alpha map from any displacement map.

Alpha maps are interresting as they can be used directly as sculpting tool for most (all?) sculpting softwares (Zbrush, Sculptris, 3DCoat, Mudbox, Blender, ...) for adding texture.

To do a good alpha you need a good displacement map with beautiful depth data. I highly recommend you to generate that displacement map automatically from 2 photos of the same subject using my new software Photosculpt Textures (download the 30-day trial here or buy it now from Eur 99). This has already been explained in this short 1'43'' video tutorial so I'm not covering it here again. Here I'm assuming you already have a displacement map at hand. Of course alternatively you can download the one on the left or 10 more in my free sample section (I also have a pay sample section from Eur 5.99)

Once you have a good displacement map, then launch your favorite image editing software (photoshop, Gimp, ...) and do the following:

Step by step: Open your displacement map and add a new layer to it, fill this layer with black, set it in color burn layer mode. Then paint a white circle in the center of it with an airbrush as shown. Save your image. Open it again in your sculpting software as alpha brush and start sculpting. Voila!

Here are some free samples for download. (click on thumnail to download)

...and how I use them:

Sculpted plane using alphas as sculpting tool. Software used: freeware Sculptris, base plane mesh subdivided 4 times before sculpting for more detail.

Advanced hints:

  • You may want to keep the alpha map size down if you encounter slow sculpting, unstable software or downsampling artefacts. I think a 300x300 pixels 8 bit alpha map are enough for most uses.
  • For best effect, if your displacement map is too gray, you may want to adjust its contrast before using it as sculpting tool
  • Instead of painting only a circle with the airbrush tool, you can paint more intricate details in your textures, hiding (with black) or showing (with white) areas of interest as you see fit
  • You can create 16 bit alphas using the 16 bit tiff displacement maps from Photosculpt. This will allow 65535 steps from front to back, witch is nicer/smoother than the default 256 steps of usual 8 bit image formats like jpg.
  • Here is a link to a good alpha community where you can download / upload your alphas: http://www.pixologic.com/zbrush/downloadcenter/alpha/

Conclusion:

In this tutorial I've shown a new way to create photorealistic alphas.

This method is I believe superior than any other method as I used 2 photos per subject and my new software Photosculpt Textures to "scan" real objects and extract real depth data from them. It's very similar to sculpting with a stamp casted from a real object if you prefer :-)

Hoping you'll like it! Dont't hesitate to comment or improve this tutorial!

Back to tutorials

References (8)

References allow you to track sources for this article, as well as articles that were written in response to this article.
  • Response
    Tutorial 12: How to create an Alpha Map for Sculpting in ZBrush/Sculptris - Tutorial dump - PhotoSculpt creates 3D models and textures from 2 photos
  • Response
    Response: plan cul dijon
    Tutorial 12: How to create an Alpha Map for Sculpting in ZBrush/Sculptris - Tutorial dump - PhotoSculpt creates 3D models and textures from 2 photos
  • Response
    Response: audreypoitiers.com
    Tutorial 12: How to create an Alpha Map for Sculpting in ZBrush/Sculptris - Tutorial dump - PhotoSculpt creates 3D models and textures from 2 photos
  • Response
    Tutorial 12: How to create an Alpha Map for Sculpting in ZBrush/Sculptris - Tutorial dump - PhotoSculpt creates 3D models and textures from 2 photos
  • Response
    Tutorial 12: How to create an Alpha Map for Sculpting in ZBrush/Sculptris - Tutorial dump - PhotoSculpt creates 3D models and textures from 2 photos
  • Response
    Tutorial 12: How to create an Alpha Map for Sculpting in ZBrush/Sculptris - Tutorial dump - PhotoSculpt creates 3D models and textures from 2 photos
  • Response
    Tutorial 12: How to create an Alpha Map for Sculpting in ZBrush/Sculptris - Tutorial dump - PhotoSculpt creates 3D models and textures from 2 photos
  • Response
    Tutorial 12: How to create an Alpha Map for Sculpting in ZBrush/Sculptris - Tutorial dump - PhotoSculpt creates 3D models and textures from 2 photos

Reader Comments

There are no comments for this journal entry. To create a new comment, use the form below.

PostPost a New Comment

Enter your information below to add a new comment.

My response is on my own website »
Author Email (optional):
Author URL (optional):
Post:
 
Some HTML allowed: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <code> <em> <i> <strike> <strong>