Description
Starfield 1.0x Field Flattener — Sharper Stars Across the Frame (55mm Back Focus)
The Starfield 1.0x Field Flattener is designed to improve the imaging performance of refractors by correcting field curvature—the reason many refractors look sharp in the centre but show softer or stretched stars toward the edges. This accessory helps produce a flatter image plane for your camera sensor while maintaining your telescope’s native focal length.
Key point: This is a 1.0x flattener (no reduction), designed around a standard 55mm back focus—making it a natural match for many DSLR imaging setups.
Who It’s For
- DSLR imagers: Designed around 55mm back focus, which aligns with typical DSLR + T-ring spacing.
- Short, optically fast refractors: A strong match for fast refractors where edge performance benefits most from flattening.
- Smaller sensors (4/3" and 1"): Smaller sensors may show less edge curvature, but flattening can still improve corner star shape.
Setup Manual (Recommended)
For spacing guidance and imaging-train setup, use the official PDF manual: Starfield Reducer & Flattener Manual (PDF) .
Why It Improves Your Images
- Flatter stars toward the edges while keeping your telescope’s focal length.
- 55mm spacing standard simplifies DSLR setups and common camera trains.
- 48mm filter thread for adding filters (e.g., light pollution, broadband).
Technical Specifications
- Type: 1.0x field flattener (maintains focal length)
- Back focus requirement: 55mm
- Clear aperture: 38mm
- Optional adapter note: Optional 48mm adapter increases clear aperture (for larger imaging trains)
- Camera connection: Standard M42 T-thread
- Filter thread: 48mm
- Optics: Multi-coated
- Body: Hard anodized aluminum (all-metal construction)
- Weight: 7.5 oz
- Adapter requirement: A standard T-ring is required (camera-specific)
FAQ
Will this change my focal length?
No—this is a 1.0x flattener. It is intended to keep your telescope’s focal length while improving star shape toward the edges.
Do I need 55mm back focus?
Yes. This flattener is designed around a standard 55mm back focus.
Is it good for DSLR imaging?
Yes—55mm back focus aligns well with typical DSLR T-ring setups. Use the manual link above if you want a spacing checklist.
Can I add a filter?
Yes—this flattener includes a 48mm filter thread for adding filters.