BIO RAD iCycler iQ Packing List And Installation Manual page 16

When the DC offset is set properly:
• The Black and White lines are as far apart as possible.
• The Black line cuts the large peak in the histogram about 1/3 of the way down from the
peak.
• The majority of pixels outside the image of the 96-well plate are in the range of 40–70
counts.
To set the DC offset:
1. Double click in the DC offset field in the Expose dialog box. Type in a new DC offset.
2. Click Expose and look at the histogram in the Gain box.
3. Continue adjusting the DC offset until it is optimized.
Before capturing an image.
DC offset too high.
Black line is too close
to White line.
White line
Black line
DC offset too low.
Black line cuts peak
too early.
14
DC offset correct.