Hi MS,
From the Volume Viewer docs (see Display: Surface/Mesh, Solid): <http://www.cgl.ucsf.edu/home/meng/docs/ContributedSoftware/volumeviewer/framevolumeviewer.html>
For surface and mesh displays, each threshold is shown as a vertical bar. Initial thresholds are set automatically. For unsigned data types, an initial threshold is set so that 1% of voxels (1% of the volume encompassed by the data region) lie above it; for signed data types, positive and negative thresholds are placed symmetrically about zero. [...] For solid displays, each threshold is shown as a small square. Initial thresholds are set automatically. For unsigned data types, initial thresholds are set to give zero intensity for the 10% of voxels (in the data region) with the lowest values, scaling up to 0.99 intensity for the 1% of voxels with the highest values; for signed data types, positive and negative thresholds are placed symmetrically about zero. I hope this helps, Elaine ---------- Elaine C. Meng, Ph.D. UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco On Aug 10, 2010, at 1:12 PM, Mitul Saha wrote:
Hi! In Chimera's Volume viewer, how is the default density threshold computed for a given loaded 3D density map? Thanks, MS