Here a small log of retracing the evolution of my equipment to take my pictures of water mites.
For my first older pictures on this blog I used a Panasonic GH1 with either the “Bokina” macro lens (90mm Tokina 90mm f/2.5 + AT-X macro extender) or the Elicar V-HQ 90mm f/2.5 1:1 (35mm) macro lens in natural light.
I purchased on “leboncoin” a trinocular magnifier. It’s a Perfex brand. Not sure of the model name. My Panasonic GH1 fit on the photo tube. For the light I use a small Ikea diod lamp and the settings I usually shoot @400ASA with the numerical zoom on the camera set on 4X. The magnifier is fixed on 45x magnification (including the 10x ocular).
I missed on Ebay a nice trinocular Leica microscope with infinity lenses and dark field possibilities.