PlaneWave DeltaRho 500 f/3 Optical Tube Assembly The DeltaRho 500 is a fast 508 mm corrected-Cassegrain astrograph with a 1537 mm focal length (f/3.03) and a flat 70 mm image circle covering more than 2.6 degrees. It is designed for wide-field surveys, space domain awareness and demanding astrophotography.
Manufacturer model: PlaneWave DeltaRho 500 f/3.03 OTA · Specifications checked against manufacturer data on 2026-11-03
The DeltaRho 500 is a fast 508 mm corrected-Cassegrain astrograph with a 1537 mm focal length (f/3.03) and a flat 70 mm image circle covering more than 2.6 degrees. It is designed for wide-field surveys, space domain awareness and demanding astrophotography.
Carbon fibre truss poles and shroud keep the tube rigid and thermally stable. Collimation software supports quick alignment, and integrated heaters keep the optics clear of dew. Optional Series-5XL focuser and Series-5 de-rotator are controlled through PWI4.
| Optical design | Corrected Cassegrain focus |
|---|---|
| Aperture | 508 mm (20") |
| Focal length | 1537 mm |
| Focal ratio | f/3.03 |
| Central obstruction | 59% by diameter |
| Image circle | 70 mm (>2.6°) |
| Optical performance | 3.86 µm RMS on-axis; 4.04 µm at 22 mm; 6.04 µm at 35 mm off-axis |
| Primary mirror | 508 mm optical / 528 mm outer, prolate ellipsoid, fused silica, enhanced aluminium 96% |
| Secondary mirror | 286 mm spherical, fused silica, enhanced aluminium 96% |
| Corrector lenses | 160 mm, broadband AR (avg. <0.5% reflection, 400–700 nm) |
| Back focus | 232.8 mm from mounting surface; 184.7 mm from lens cell; 147.6 mm with Series-5XL focuser and rotator (extension spacer required) |
|---|---|
| OTA length | 892 mm (35.1") |
| Weight | 75 kg (165 lb) |
| Tube | Carbon fibre truss poles with carbon fibre shroud |
Wide Saddle on L-500/L-550/L-600. Series-5XL focuser + Series-5 rotator need extension spacer.
| Bf (mm) | 232.8 mount; 184.7 lens cell; 147.6 with S5XL+rotator |
|---|
Ficha técnica
PlaneWave DeltaRho 500 f/3 Optical Tube Assembly The DeltaRho 500 is a fast 508 mm corrected-Cassegrain astrograph with a 1537 mm focal length (f/3.03) and a flat 70 mm image circle covering more than 2.6 degrees. It is designed for wide-field surveys, space domain awareness and demanding astrophotography.
Manufacturer model: PlaneWave DeltaRho 500 f/3.03 OTA · Specifications checked against manufacturer data on 2026-11-03
