The values you have measured for offset are looking correct.
You can use AWG output for gain calibration (select DC - adjust offset). The same method is used for factory calibration.
Values from factory calibration are stored in EEPROM. They can be read using the software menu: EPROM -> Read Calibration (software must be run "as administrator"). After selecting this command, the calibration data will be read out from EEPROM to the file on disk.
The calibration data will be located
in windows: <scopefun_installation_dir>/data/startup/hardware2.json
on linux: /usr/lib/oscilloscope/data/startup/hardware2.json
Below is an example of offset calibration data:
"callibratedNormal": {
"offsetsCh0": {
"volt2": -47,
"volt1": -48,
"mili500": -51,
"mili200": -60,
"mili100": -47,
"mili50": -48,
"mili20": -52,
"mili10": -61
},
"offsetsCh1": {
"volt2": -23,
"volt1": -25,
"mili500": -27,
"mili200": -35,
"mili100": -23,
"mili50": -25,
"mili20": -28,
"mili10": -35
},
And similar for gain calibration data:
"gainValueCh0": {
"volt2": 1423,
"volt1": 1777,
"mili500": 2129,
"mili200": 2596,
"mili100": 1417,
"mili50": 1768,
"mili20": 2244,
"mili10": 2599
},
"gainValueCh1": {
"volt2": 1425,
"volt1": 1779,
"mili500": 2129,
"mili200": 2587,
"mili100": 1419,
"mili50": 1770,
"mili20": 2241,
"mili10": 2594
},