Continuing the scanning of a range of objects

Simple scan of the back of a paper payslip. Much more vibrant blues than actually present. I also asked the scanner to just select the document and it seemed to do a reasonable job.

Then I tried a leaf:
Lid up of course. Not really finding any difference on the effect of the background between having the light on in the room or not.

Then a handkerchief
Bubble wrap:
Wasn't sitting flat against the glass hence the different tones and reflections.

Then tried handsoap in a plastic tray:
I think the liquid needs to be backlit. I tried a torch but too powerful, just flooded everything with light. Tried torch from different distances but difficult to get the backlight and frontlight in balance.