The 100x is an oil immersion and demands special techniques.
The reason you use two lenses is to cut down on distortion. Leeuwenhoek's idea was really strange and basically uses one very big ocular.
]]>By the way, I know the objectives:
Scanner 4x
LPO 10x
HPO 40x
OIO 100x
Then multiply by 10x to get the total magnification.
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