Product Description
This imported field flattener was used by us for years until we developed our own in-house field flattener (SFFX1). These are the remaining stock of generic 2.5" field flatteners that normally sell for about $285. These do vary a bit so it may be necessary to modify the actual back spacing. These may be used for a variety of refractors by changing the amount ofextension you add to them. The extensions needed are our M69 extensions. Back-focus from the rear of the flattener is about 86 mm for long focus refractors to 107 mm for short focus refractors.
Optional adapter: Also available as an optional purchase is the 36 mm adapter which provides about 55 mm of back focus when used with a 102 - 115 mm f-7 refractor. This adapter screws into the back (camera-side) of the flattener and it has an M48X.75 thread on the camera side. Additional extension tubes and spacer rings are available on our M69 extension pages. Adapters that convert the M69 female thread tovarious camera threads may be found on our adapter pages.
