Making alpha from current sculpt

To create an alpha from a sculpt room object do this:

File menu in the sculpt room. Choose export depth along  Y.
Make sure your model is facing Y up and centered in world space. 
Uncheck everything
Set your texture size and the patch size which is the size of the alpha in the image.  Smaller patch size numbers will increase the amount your sculpt alpha fills the inside of your texture image space. Patch size 100 is ok. Higher makes small, lower almost crashed 3DC.

– Be aware even though I select tif, 3dc tries to export as exr. tif is 32bit still.
– Can go 16K, huge file size.
– Important: ZB couldnt read 32bit tif, needed to convert to 16 bit in PShop. Created displaces works fine.

You can use tiff as it creates a 16 bit image. Exr work well except that it is a 32 bits format making huge file and you have to do another manipulation in Photoshop if you want to drop it to 16 bits.

Note: Color can be deselected in the dialog box unless you want a separate color image too.