Bio-Rad Image Lab™ Software - Manual (Page 174)

A | Maintaining the GS-900 Densitometer
174 | GS-900 Calibrated Densitometer with Image Lab Software
stain. Ensure that both the sample glass and the glass on the transmission
module are clean and free of scratches.
To reset the GS-900 densitometer
1. Start Image Lab.
2. Ensure that the lid on the GS-900 Densitometer is lowered.
3. From the Edit menu, click Instrument Setup.
The Instrument Setup dialog box appears. From this dialog box you can
relocate the calibration standard and reacquire the flat field values.
4. Click Reset for the calibration that you need to perform.