Product Overview
The 48mm T-Adapter (#93622) is the essential accessory for astrophotographers wishing to attach a full-frame DSLR, Mirrorless, or dedicated astronomical camera to a Celestron EdgeHD optical tube (9.25", 11", and 14").
As modern camera sensors get larger, standard adapters can clip the incoming light cone. Celestron developed this 48mm T-Adapter to widen the light path, significantly reducing vignetting and unlocking the full imaging capabilities of large sensors.
42mm vs. 48mm T-Adapter Comparison
The standard T-Adapter for EdgeHD telescopes utilizes a 42mm T-Thread (compatible with 42mm T-Rings). However, this narrower 42mm opening truncates the light cone originating from the rear of larger EdgeHD optical tubes, leading to noticeable corner darkening (vignetting) on full-frame sensors.
In contrast, the 48mm T-Adapter features a larger thread opening, allowing unhindered light to illuminate the entire camera sensor for crisp, evenly lit astrophotographs.
Visual comparison of inner clear aperture space between 42mm and 48mm T-Rings.
Sensor Compatibility & T-Rings
T-Ring Requirements: T-Rings are sold separately. Celestron does not manufacture 48mm T-Rings directly, but compatible 48mm T-Rings (M48 x 0.75 thread) for Canon, Nikon, and Sony cameras are widely available from suppliers such as Sky-Watcher USA.
Illumination Performance Chart
The chart below illustrates sensor illumination performance when using a 42mm vs. a 48mm T-Adapter:
- X-Axis: Distance from the center of the camera sensor (mm).
- Y-Axis: Relative percentage of light received by the sensor.
As shown, the 48mm T-Adapter delivers significantly higher edge illumination, preventing light fall-off across full-frame sensors.
Technical Specifications
| Compatible Telescopes | EdgeHD 9.25", EdgeHD 11", and EdgeHD 14" |
|---|---|
| Camera Thread Standard | M48 x 0.75 Note: Incompatible with M42 x 0.75 T-Rings |
| Flange Distance | 91 mm (3.58 in) |
| Outside Diameter | 72 mm (2.83 in) |
| Product Weight | 226.8 g (8.0 oz) |