Z offset / scale soft_scale is `None`

[Edoardo Zatterin]

Hi,

I have some piezoresponse data which seems to give problems to your code. If I run:

import nanoscope as n
import io

file = io.open('fname','rb')
n.nanoscope.NanoscopeFile(file,header_only=True).config['_Images']['Phase']

I get:

{'Aspect Ratio': '1:1',
 'Bytes/pixel': 2,
 'Capture start line': 0,
 'Color Table Index': 12,
 'Data Type Description': None,
 'Data length': 262144,
 'Data offset': 867392,
 'Data type': 'AFM',
 'Description': 'Phase1',
 'Frame direction': 'Down',
 'Highpass': 0,
 'Image Data': 'Phase',
 'Invalid Data Fill': None,
 'Invalid Data Flag': None,
 'Line Direction': 'Retrace',
 'Lowpass': 0,
 'Note': None,
 'Number of lines': 256,
 'Offline Planefit': None,
 'Plane fit': 0,
 'Realtime Planefit': 'Offset',
 'Relative frame time': 2561.29,
 'Samps/line': 256,
 'Scan Line': 'Main',
 'Scan Size': 500,
 'Start context': 'OL',
 'Tip x width correction factor': 1,
 'Tip x width correction factor sigma': 1,
 'Tip y width correction factor': 1,
 'Tip y width correction factor sigma': 1,
 'Valid data len X': 256,
 'Valid data len Y': 256,
 'Valid data start X': 0,
 'Valid data start Y': 0,
 'Z magnify': 1.0,
 'Z offset': Z offset: [None] (0.005493164 º/LSB) 0.0 deg,
 'Z scale': Z scale: [None] (0.005493164 º/LSB) 360.0 deg}

Where you can see that Z offset and Z scale are set to None. So that when I run:

import nanoscope as n
import io

file = io.open('fname','rb')
n.nanoscope.NanoscopeFile(file,header_only=True).config['_Images']['Phase']['Z offset'].soft_scale

There is no output. Hence nanoscope.read breakes while running the _get_sensitivity_value function. Is there quick fix that you can suggest by any chance?