[Chimera-users] Scale bar in Chimera

[Thomas Goddard]

Hi Haixiao,

  The Chimera scale bar is positioned in 3 dimensions -- it has a certain
depth in the scene.  The depth is important because Chimera uses perspective
projection by default -- so things closer to you appear larger.  So it is
important to position the scale bar depth to match the depth of the model
or feature you are trying to measure.  You can do this by clicking on
the "Move scale bar..." switch in the Scale Bar dialog and then using
dragging with ctrl button 2 to adjust the depth.  It will be helpful to
look at the side view (Favorites / Side view) while doing this to see
where the scale bar is relative to the model in the depth dimension.

  Another solution to this problem is to switch to orthographic projection
mode.  Use Favorites / Side View and switch to the Camera tab and change
the "projection" menu value from perspective to orthographic.  Then the
whole scene is projected perpendicular to the screen.  Closer objects will
not appear any larger than far objects in that mode.

    Tom