Tools & Microfiber2 min read

Contact-Angle Baselines: Locate the Actual Surface in the Image

The baseline used in drop-shape analysis represents the sample surface. An incorrectly placed baseline can change the reported angle even when the underlying droplet has not changed.

Updated · NANOLAB Knowledge

The key distinction

KRUSS explains contact angle through the relationship between the fitted contour and the surface baseline. Preserve the image and baseline placement so a reviewer can assess whether the analysis represents the specimen correctly.

Practical checks

  1. Confirm that the surface boundary is visible in the image.
  2. Review automated baseline placement where the method requires it.
  3. Retain the original analysis for traceability.

Example

Illustrative example: a reflection beneath a drop is mistaken for the surface boundary. The resulting angle may look precise, but the analysis is based on the wrong geometry.

Scope and limits

Do not adjust the baseline merely to match a desired value. This guide does not provide a universal image-analysis procedure; follow the instrument method and appropriate laboratory review.

Related guidance

Technical references: KRUSS: drop-shape analysis. These sources describe their stated methods or products; they do not certify NANOLAB products or establish compatibility with an unlisted surface.

Ask NANOLAB about the exact product and intended use. Use the current product documentation for formulation-specific instructions.