In order to be able to scan on the go with good lighting conditions, I am currently developing a movable holder for a ring light. As a ring light, I ordered a simple one with an adjustable light and a diameter of 29 cm. Also it is powered by USB so a Powerbank will be enough.
If you want to make your own you can download it on printables.com for free.
The only additional things needed are two tripod screws, a ball-bearing and of course a printer.
This is a work in progress so I will update the files from time to time.
I welcome ideas and suggestions for improvement.
The first one I had directly after the first scan - you need to use warmer light Tones because the scanner will loose track with cold/blue light.