3.5" Prime Focus Field Flattener for 140 TEC Refractors or 140 StarFire with 4" or 3.5" Focuser (14035FF)
Brand : Astro-Physics
- SKU:
- 14035FF
- Availability:
- Mid-January 2025
December 2022 - This field flattener was introduced to optimize performance of the 140mm refractors from Telescope Engineering Company (TEC) or Astro-Physics 140mm f7.5 StarFire with either a 4" or 3.5" focuser.
Field flatteners are designed to accurately compensate for the inherent field curvature of a refractor lens. For each lens design there is an optimal spacing that works best for sharp focus over the specified field size. As camera designs have advanced, the performance requirements have become more stringent. This is now especially important when using the newest CMOS cameras with pixel sizes of 3.76 microns and smaller. This field flattener has been optimized for these 140mm refractors.
14035FF Includes
- Field Flattener housing with optics optimized for this version
- 3.27" Spacer Rings , Set of 3 Rings (SRSET-327)
- Two beautifully machined and black anodized covers
- 14035FF Decal to differentiate from similar assemblies
Back-focus Spacing from the Rear Flange
Back-focus spacing is 3.2597" +/- 1/10" (82.8 mm +/- 2.5 mm) - measured from the back flange of the TCC to the camera sensor.
Spacer rings (1mm) are provided to achieve the 80.80mm spacing on which our various adapters are designed.
Use with CMOS Cameras to 35mm
Adapters are available for use with CMOS cameras with thread sizes of 48, 54 and 68mm. These are designed for the popular CMOS cameras currently available that utilize the 55mm standard spacing. The SRSET-327 Spacer Rings (included) are required for this image train.
ADA327-48, 3.27" to M48 Adapter (new July 2024)
ADA327-54, 3.27" to M54 Adapter (new July 2024)
ADA327-68, 3.27" to M48 Adapter (new July 2024)
Use with Canon EOS and Nikon DSLR and Mirrorless cameras
We recommend using the required Back-focus Spacer, which will provide back-focus spacing of 80.8mm for coupling directly to our camera adapters below.
- Canon EOS Camera Adapter with large 1.875" (47.6mm) diameter stainless steel bayonet. (ADATCCEOS)
- Nikon Camera Adapter with large 1.73" (44mm) diameter stainless steel bayonet. (ADATCCNIK)
- Canon EOS Mirrorless Camera Adapter with large diameter stainless steel “RF” Lens bayonet. (ADACAN-RF)
- Nikon Z Mirrorless Camera Adapter with large diameter stainless steel “Z” Lens bayonet. (ADANIK-Z)
Adapter Required to Adapt to Your Focuser
Astro-Physics 140 Starfire with 4" Focuser: Will need ADA435, 4" to 3.5" Adapter.
TEC140 scope: You will also need to order a Drawtube Endcap (S35RFAA), shown below, for the focuser. This only applies to the TEC focusers. The S35RFAA screws onto the drawtube's 4.100" x 24 thread (same as Starlight Instrument's 3.5" focuser endcap thread).
Custom Adapters
If you need an adapter that is not listed above, we recommend that you contact PreciseParts. You may also review the following diagram that shows additional components you might find useful. Keep in mind that some are legacy parts: Field Flatteners, TCCs & QUADTCC Imaging Train Options
Diagrams and Instructions
- Astro-Physics Prime Focus Field Flatteners - Outdated exploded diagram showing the field flatteners with a variety of accessories, but you may own some of these items.
-
If you own items not shown in the diagrams above, please refer to the Discontinued Products section of this website and Technical Support for Legacy Products that are No Longer Available
Astro-Physics 80.8mm Back-focus Spacing Distance
For more information regarding the concept for the 80.8mm back-focus spacing distance, refer to this webpage: Spacers & Extensions
.