Fixing our LM-Digital Adapters requires a C-Mount thread on the microscope side which is supplied by the respective microscope company. This C-Mount thread is standardized internationally and has the following dimensions: 
M25,4 x 0,75 or 1” x 32G/”. 
 

Tubus length 

If parafocality (a sharp picture both in the visual eyepiece and in the digital camera) is considered important, you must make sure that all tubus lengths are equal. This is the case when the optical distance of the photo tubus (P) and the eyepiece tubus (B) is the same. For fine tuning adjust the diopters in the visual eyepiece tubus.
 

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