The working distance of a stereo is the distance the objective can be from the specimen and still focus. This is an important consideration in a stereo microscope due to the sometimes very large and bulky things placed under it, especially when dealing with an object with many irregular shapes. At 170mm, the LOMO SF-50 Stereo Microscope has one of the longest working distances of any stereo microscopes on the market. _________________ Thanks for posting with us
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