CrysAlis^Pro Tip

Frame Masking Tools

What is the issue?

Certain areas of diffraction images can sometimes be masked to improve data analysis. Diffraction images from high-pressure experiments may exhibit features of the diamond anvil or the gasket material, which could hamper determination of the unit cell. Another case is when area detectors exhibit untreated bad pixels, which may happen, for example, in foreign datasets from synchrotrons.

How to apply masks

CrysAlis^Pro allows you to mask rectangular features and ring-based (d-value) features.

Rectangular features:

Drag a box around the feature you want to mask with your mouse by holding down the left mouse button. Click on the right mouse button and select Reject rectangle.

This feature can be used for single images (choose run and frame number) or for the whole dataset (choose run and frame number as zeros).

The masked area can be displayed by choosing Show reject rectangle in the submenu next to the RED/USER switch.

Ring-based features:

First select the Line select (for skip d-value) via a right mouse button click.

Then the range of d-values which should be excluded from data analysis can be selected on the diffraction image. Click the right mouse button and select Skip d-value.

The masked area can be displayed by choosing Skip d-value overlay in the submenu of RED/USER as before.