CrysAlisᴾʳᵒ Tip: How to Configure and Adjust CryoJet Shadow Masks

Learn the step-by-step process for setting up a mask in CrysAlisᴾʳᵒ to account for the shadow cast by a cryo nozzle (jet) on your diffraction images. Proper masking is essential to ensure that the software knows where reflections should not be measured.

Key topics covered in this video:

Initial Alignment: Ensuring your cryo nozzle is correctly aligned using an alignment pin before you begin masking
Visualizing the Shadow: How to swing the goniometer to extreme angles (positive and negative 2θ) at a close distance to capture a raw image of the nozzle's shadow
Using Masking Tools: Accessing the "adjust beam stop XY center" tool and toggling the "use jet shadow" and "beam stop overlay" features
Adjusting Parameters: A deep dive into the four main parameters used to refine the mask
α Angle: The angle of the jet relative to the vertical
β Angle: How far the jet is from being straight over the X-ray source
Jet Width: The width of the nozzle tip
Distance to Jet: The distance from the crystal to the end of the nozzle
Refinement & Verification: Tips for "fiddling" with the parameters—starting with α for angular adjustments—and the critical step of verifying the mask on the opposite side of 2θ
Saving Your Setup: How to document your final values and ensure they are correctly set in the crystal's name parameters/edit options

Pro Tip: Always check both sides of the detector to ensure your parameters agree across the entire range of motion

Presenter

Mark Del Campo, PhD | Senior Applications Scientist

Rigaku Americas | Texas, USA

Mark Del Campo is a Senior Applications Scientist at Rigaku Americas Corporation with over 20-years-experience in the life sciences. He has traveled the world supporting Rigaku’s macromolecular crystallography and small angle X-ray scattering customers for 9 years. Mark did his postdoctoral research on fungal DEAD-box proteins and Group I and Group II introns with Dr. Alan Lambowitz at the University of Texas at Austin, where he solved 8 structures deposited in the PDB. Mark received his Ph.D. under the supervision of Dr. James Ofengand at the University of Miami, where he worked on E.coli pseudouridine synthases and solved 3 structures deposited in the PDB. Mark was the recipient of both predoctoral and postdoctoral Ruth L. Kirschstein National Research Service Awards.