The Mudbox file format architecture was substantially changed for Mudbox 2009 to improve interactive performance using models with much larger polygon counts. Unfortunately, the .mud files from Mudbox version 1.0.7 or earlier are not upward compatible with Mudbox 2009 or later versions.
The following techniques describe how to transfer sculpted models from Mudbox 1.0.7 (and earlier versions) to later Mudbox versions using the .obj file format.
File transfer using .obj file format and re-creating the subdivision levels
This technique requires you to output two .obj files from the Mudbox 1.0.7 version model: One from the base subdivision level, and one from the highest subdivision level that contains your sculpted detail. You then import these two files into your newer version of Mudbox after you recreate the same subdivision level structure as in your original Mudbox 1.0.7 file.
Use the steps in this section if your Mudbox version 1.0.7 or earlier file contained multiple subdivision levels and was not using local subdivision on the model. If the model used the Subdivide Selection feature (obsolete as of Mudbox 2009), these instructions will not work and you’ll need to use the second method described in File transfer using the Sculpt Model Using Displacement Map feature.
At this point, you have the same base subdivision level of the model as your model from Mudbox 1.0.7.
Keep the highest subdivision level active for the next step.
This recreates the highest subdivision level of the Mudbox 1.0.7 model in the newer version of Mudbox. When you step down using the Page Down key, you will see all of the sculpted information on subdivision levels in between.
File transfer using the Sculpt Model Using Displacement Map feature
This technique requires you to output two files from the Mudbox 1.0.7 version model: one .obj file from the base subdivision level, and one extracted high resolution displacement map from the highest subdivision level on the model. You then import these two files into the newer version of Mudbox after you recreate the same subdivision level structure as in the original Mudbox 1.0.7 file.
Use the steps in this section only if your Mudbox version 1.0.7 (or earlier) model contained local subdivision. That is, if the model used the Subdivide Selection feature (obsolete as of Mudbox 2009). Otherwise, the instructions described in the previous section can be used.
The Extract Texture Maps window appears. You need to extract a displacement map of the sculpt features that appear on the highest level.
At this point, you should have the same base subdivision level of the model that was in Mudbox 1.0.7.
This recreates the highest subdivision level of the Mudbox 1.0.7 model in the later version of Mudbox. When you step down using the Page Down key, you will see all of the sculpted information on subdivision levels in between.