Data Collection

After the beam line has been properly aligned, you have checked the sample goniometer alignment, and you have mounted and aligned a sample, you are ready to collect an image. The sergui collect page has 3 sub pages: Collect Single, Collect Runs, and Collect Strategy.

Collect Single

The Collect Single page provides the user with the capability to take single images at different angle to check sample alignment and quality.

The sample ID is used to form the image file name. Next to the sample ID is a number selector which will also become part of the image file name. The file name is shown in blue. The complete file name will have an _s appended to it to indicate that it is a single image. In the case shown, the file name root of sample becomes a file name of sample_s.0001 after the number 1and s are appended to the name.

The short term archive directory can either be manually input or browsed for. The long term archive directories can not be used for data collection.

The next 4 sections (X-ray, Attenuation, Detector, and Exposure are used to setup the data collection parameters. When the data collection parameters have been set, the image is collected by pressing the green Collect button.

Once the user is ready to collect a data set, it is highly recommended that the Collect Strategy page be used to set up the data collection run list. Note that the top area of the Collect Strategy page is identical to the same are in the Collect Single page.

This page provide two functions for the user: Its primary function is to simplify the run list generation; its second function is to collect a limited amount of data and provide the user with a data collection strategy.

Goniometer: This section is used to determine the data collection parameter: exposure time, starting angle, scan width, number of frames, and detector distance.

Wedging: This section is used to setup wedged data collection, either in angle, wavelength, or in both.

Energy: This section is used to define the data collection energy or energies in the case of a MAD experiment.

Strategy Data Collection: This section is used to setup an automated data collection and processing run, which will provide the user with a data collection strategy.

How do I?

Q: Setup up a single wedge of data at 1 energy?

A: Enter parameters in the Goniometer section. Make sure that all of the buttons in the Wedging section are pressed N. In the Energy section, make sure that the Starting Energy has the correct value, and that the other energy buttons are NOT checked. Once this is done, press the generate Runlist button.

The run list on the Collect Runs page can be edited by hand.

Q: How do I setup an inverse beam experiment at a single wavelength?

A: The only change from a single wedge of data is to press the inverse beam button in the wedge section.

Note: 2 data sets will be generated from this data collection run. The ID number (second labeled column on the Collect Runs page) is used to differentiate the 2 different data sets: the 2 data sets will be named single_wedge1_1.#### and single_wedge1_2.####.

Q: What if my sample is radiation sensitive and I want to collect a SAD data set wedged in angle?

A: In this case, The Collect Data Wedged in Angle must be pressed and a value for the wedge size supplied.

Note: The system will still only provide 2 data sets for this data collection run, not the 6 that are identified in the Collect Runs page. The ID number is once agina used to append the frames onto the 2 data sets single_wedge1_1.#### and single_wedge1_2.####.

Q: What if I want to collect MAD data in inverse beam mode wedged in Angle and Energy?

A: For this complicated data collection strategy, the user will need to just set the Collect Data Wedges in Energy button to yes, enter a second energy in the Energy section and check the use in data collection button for the second energy.

Note that in this case, the run list has 4 ID numbers identified, so the end result will be 4 data sets representing the inverse data sets at each of the 2 selected energies.

Q: So how do I collect my Data?

A: Press the Collect button at the bottom of the Collect Runs page.

Q: Can I pause and restart the data collection?

A: Yes, after the data collection has begun, an abort button will appear at the bottom of the Collect Runs page. Press this button and the data collection will stop after the current frame.

Q: Can I resume my data collection after it is aborted?

A: yes, to continue with the next frame, just press the collect button. If you want to step back some frame, then change the number in the next field to indicate which frame you want to start on and then press the collect button.

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