h1.Which Calibration Tag Should I Use?

Occasionally, multiple calibration versions are valid at the same time, so the default tag in Calibrator.fcl is not sufficient for everyone. If you use a recent version of develop on older files, you will need to set your Calibrator tag manually in your job file. Here are the valid Calibrator versions as of Spring 2017:

services.Calibrator: @local::v9_calibrator       # Second Analysis
services.Calibrator: @local::v10_calibrator     # Miniproduction 2016
services.Calibrator: @local::v12_calibrator     # Third Analysis

If you don't set this, your job is likely to break when looking for a CSV file it thinks should exist, but actually should not. Frequently, this will be because your job detects a fiber brightness model saved in the art::Run in your data files, which leads it to expect a ".fbX" string in the CSV name -- if you are using a calibrator version when does not calibrate per fiber brightness bin (v12 ND), such a CSV will not exist. Conversely, If you are using a calibrator version which does calibrate per fiber brightness bin (v12 FD) on files without a brightness model, your job will break looking for nonexistant CSVs without the ".fbX" string in it:

Loading attenuation cache consts from /grid/fermiapp/products/nova/externals/calibcsvs/v12.01/NULL//csv/v12/
Couldn't open 

In some Miniproduction 2016 files, you may have some luck forcing the brightness model, therefore the ".fbX" string in the CSV name, with

services.FiberBrightness.ReadFromFile: true

but this is only because the brightness model was mistakenly left out of the files. Doing this with other files will technically let your job run, but may introduce incorrect light scale factors.