Processing for the price is more than ok. The mounting of the ring on the adapter is a good solution. It's also nice that no cable to a battery is necessary and the Schwerkunkt is in the middle. However, the weight of the ring cause the lenses begin not crawl to crawl when mounted vertically on the copy stand alone (adjustment focus by weight). Illumination with very little distance to the object (2-3cm from front ring light) is also ok. But so far not only visually photographed and tested (eyepiece instead of behind camera lens until 25x to 125x magnification on Repro Stand).
