Nikon F Mount Lens to Scope Adapter

prusaprinters

ABOUTThis threaded adapter replicates the camera body portion (female side) of a Nikon/Nikkor F-Mount on one end, and male 1 3/8" x 24tpi threads on the other.   It allows the user to mate eyepiece mounting accesories designed for Meade ETX-90 (and other smaller Cassegrain telescopes with the same threads) to a standard F-Mount camera lens.  This combination allows visual eyepieces to be connected to a telephoto camera lens, converting the lens to a small telescope.  Flange to flange thickness (what you see when everything is threaded together) is 7.8mm.This adapter was tested with Celestron XCel 5mm, 7mm, 12mm, and 24mm eyepieces in combination with a vintage Nikon/Nikkor 180mm ED AiS F/2.8.  All came to a sharp focus and provided crisp images day and night.  Also used for testing were Antares Speers-WALER eyepieces, which require an uncommon amount of back focus.  These could not be made to focus at infinity.  Any eyepiece requiring less than roughly 7.8mm of spacing between the camera lens rear element and eyepiece barrel will not focus at infinity, but eyepieces with such a requirement are few and far between.The specific eyepiece  adapter shown in the photos is designed for Meade ETX-90s and can be found at: http://www.scopestuff.com/ss_etxa.htm PRINTINGPrinted in Overture PETG.  PLA will work but lacks heat resistance if these will be stowed with photo equipment during travel.  Other heat resistant, stiff filaments will work.3 line wall thickness, 25% infill, adaptive layer height or minimum of 0.16mm layers recommended for maximum resolution of the threads.Print with camera-side down, with supports under bayonet surfaces and interior “roof”.Ensure to thread this adapter snugly (but just snug) against your eyepiece mount of choice.  When sandwiched between two objects (camera lens and eyepiece mount), the delicate plastic threads of this adapter are largely stressed only axially with the force of the thread torque, from front to back of the lens system.  If any gap is left between this adapter's flanges and the lens mount or eyepiece mount, the threaded portion's thin walls are more susceptible to lateral deflection and could shear off.