I used the Panagor 55mm f/2.8 macro lens with an adapter from canon fd to m43.
Yes, it was natural light. I build a setup in my living room next to a large window. I placed the dandelion seed in a plate using some modeling clay and filled it with a mixture of milk and water. The sun was shining from behind me, the setup was in the shadow. For the first image I used a reflective red paper to bounce the sunlight back on the milky water. For the second image I placed a dandelion flower behind the seed with the droplet, here everything was in the shadow and no bouncing of sunlight used.