Calibration: better way to switch off old calibration

[Gesner Passos]

Currently, to calibrate, for example, MERLIN instrument. We have to follow instructions found http://www.mantidproject.org/Tube_Calibration_Examples#Running_TubeCalibDemoMerlin.py.

The procedure of switching off code from the instrument parameters and than later, having to remember to switch them on again is error prone.

So, it is necessary to find a new way to switch off old calibrated values when performing the calibration. A strategy may be to execute the loadinstrument algorithm.

[Gesner Passos]

Export baseInstrument to python

The baseInstrument has the information of the positions of the detectors before loading any calibration values. Using the information from this object it will not require disabling loading the calibration values any more.

re #7491

Changeset: 3148a7794a053329ffc2dd7bb0da893f945b455e

[Gesner Passos]

Use the detectors from baseInstrument

It nows use the position from the baseInstrument which is free from any previous calibration being applied to the detectors.

The only issue that it introduces is that you can not calibrate instruments that was moved or rotated before the acquisition of the data. Because, the baseInstrument does not consider this. Besides, any previous movement for the detector will be reset when applying the output of the calibration.

But, we consider these limitations better than having to switch off loading the calibration values through comment the region det-pos-source.

re #7491

Changeset: 32e531a1da884b5157ca40328b624a26a9080d4a

[Gesner Passos]

Tester:

If everything works fine. Now, you should be able to open an already calibrated file, and apply the calibration, having a nice result. In order to see this, I've given you the testingMerlingCalibration.py.

Do not execute it all at once. Select part of the code till the frase "Pause and see the instrument check". Make sure the instrument preserves the previous calibration, but that the calibration of the part of the instrument that is being applied works nicely.

Repeat the same operation till the end of the file.

[Anders Markvardsen]

reason for reopen when running

from Examples import TubeCalibDemoMerlin as mer mer.calibrateMerlin('MER12024.raw')

not same result

[Gesner Passos]

Define the fitPar from the baseInstrument

It is wrong to take the length from the calibrated tube and applying to the baseInstrument.

re #7491

Changeset: 4c88cae40be0e8e386f89a6704b4e0a1f4aea07f

[Gesner Passos]

Correct the Merlin Example

There were lacking tubes inside the door3.

re #7491

Changeset: 3a736cf96af00bbe9b6b8ee375d610a6dfb0b98c

[Anders Markvardsen]

Merge remote-tracking branch 'origin/feature/7491_reset_calibration'

[Anders Markvardsen]

Running

from Examples import TubeCalibDemoMerlin as mer mer.calibrateMerlin('MER12024.raw')

gave expected result

[Stuart Campbell]

This ticket has been transferred to github issue ​8336