Preferences: Tracing
You need a reference point to be able to modify these parameters.
View
Place points in continuous tracing
This adjustment controls how smooth the tracing is when using continuous tracing mode (see above).
- more: smoothest curves, but places more points in the data set.
- fewer: fewer data points for a given curve, but the curve is not as smooth.
The smoothness of the traced curve must be balanced against the overhead of more data points. Curves with many points are harder to edit.
Display line thickness
Displays the thickness of the lines used to trace contours or trees.
- Select one of four rendering methods: tapered thickness, next point’s thickness, thickness ratio (larger), thickness ratio (smaller).
To control line thickness, there are three options:
- Go to File>Preferences>Cursor and modify the cursor diameter under Settings.
- Use the + and - keys on the numeric keyboard.
- Scroll the mouse wheel.
The lines you see are representations of three-dimensional cylinders and frusta. When the 3-dimensional tracing is displayed on the flat screen, the result is a thick line if thickness is turned on.
Double-click closes contour
Check this box to close contours with a double-click instead of right-clicking or selecting an ending type from the Trace ribbon.
Show drawn objects in
Color
Objects are drawn using the colors that you select.
Monochrome
Use in conjunction with the monochrome Lucivid. It is possible to switch back to color for editing and visualization when using the computer monitor.
Some of the features displayed in the tracing window may be displayed slightly differently to make up for the information conveyed by the colors. For example, the exclusion and inclusion lines of the counting frame will be represented by white solid and dashed lines, instead of red and green lines, respectively. 
Dim Monochrome
Use when the bright monochrome display overpowers your image. This is useful when using the Lucivid to trace very dim structures, such as weak fluorescent stains.
Tracing transparency
Adjust the transparency to see the object you are tracing while tracing.
Warn me when Z changes exceed ...
The Z deviation warning is intended to detect problems in tracing dendritic structures. Tracing branched structures involves many steps during which mistakes can introduce large jumps in Z. Since Z is the dimension going into and out of the screen it is not always clear that points are not close to each other in Z. The warning discriminant is a micron value. A warning is flagged if the difference of the Z coordinates of two sequential points exceeds this discriminant.
Markers
Contours