This works well for me.  I take any microscope (mantis too) and get a digital camera.  Put the part that you want to photo under the scope then take the camera to one of the eye pieces or to one side of a mantis.  Be patient and make slow movements left and right the camera will be able to look through the eye piece.  I have been extremely successful using a simple digital camera and with a scope that has a wide range I can take whatever detail photo I need. 

 

I suppose you can also buy something but I haven't been able to justify a more pretty set up. 

 

Kathy