The SFFX-2 field flattener is no longer available. It has been replaced with the new SFFX-3. The SFFX-3 should not be confused with the SFF3 which was an old imported flattener we sold years ago. The new SFFX-3 is our latest, improved design. It will fit more cameras, does not vary in back focus as the SFFX-2 did, and has a much longer back-focus (permitting the use of additional accessories such as a rotator).
This photographic field flattener was designed to work with our 130 mm - 180 mm refractors and it requires the proper extensions and adapters needed for your telescope and camera combination. The optimum distance from the back of the flattener to the camera's sensor varies depending on the telescope used.
Mounting your camera to the field flattener: We sold these flatteners optimized for our various telescopes by providing different extension tubes. For best results, the field flattener must be placed at a precise distance from the camera sensor. Since many customers have camera trains of different lengths, we manufacture and offer various extension tubes and spacer rings to accommodate a wide variety of camera set ups. These M69 extensions are found here.
When we sold SFFX2 field flatteners for a particular telescope we supplied them with a camera adapter to match the thread size of the customer's camera. We supplied these thread size adapters:
- M42
- M48
- M54
- M68
- 2.156
- 3"-24
Some imaging cameras do not adhere to the standard 55 mm spacing. In this case, the SFFX-2 could be provided with different length extensions to adjust for this to a limited extent.
If the distance to your camera's sensor is not 55 mm refer to the picture below. This picture shows the SFFX2 with the M69 extension tube and camera thread adapter removed. As you can see, the optimal distance to the camera's sensor without these parts varies when you use the flattener with different Stellarvue telescopes. Use the picture below to determine which extension tube(s) you need with your particular camera backfocus. Again, the extensions and spacer rings may be found here.
Mounting your field flattener to the focuser: The front of the flattener threads directly to the Feather Touch 3.5" focuser when the 2" adapter and the M75 - M88.5 adapter it screws into is removed (unthreaded) from the focuser. When using the SFFX-2 with the 3.5" Moonlite focuser, use the threaded Moonlite to SFFX2 adapter.
Feel free to call us at (530) 823-7796 or email us at mail@stellarvue.com if you have any questions.
Weight with adapters is 2lb 1oz.
