Explore Scientific HR Coma Corrector — 2-inch high-resolution corrector for fast Newtonians The Explore Scientific HR Coma Corrector (item 0510330) is a four-lens, 2-inch corrector for Newtonian telescopes. It corrects coma, field curvature and astigmatism, and Explore Scientific specifies it for very fast systems down to f/3.
Manufacturer model: EXPLORE SCIENTIFIC HR Coma Corrector (0510330) · Specifications checked against manufacturer data on 2026-11-03
The Explore Scientific HR Coma Corrector (item 0510330) is a four-lens, 2-inch corrector for Newtonian telescopes. It corrects coma, field curvature and astigmatism, and Explore Scientific specifies it for very fast systems down to f/3.
Explore Scientific describes the corrector as diffraction-limited on axis and across the field, with a flattened 30 mm usable field. It quotes a visual polychromatic Strehl of 0.98 at f/4 and 0.96 at f/3, measured on a flat field without refocusing. The corrector lengthens the system focal length by only about 6%.
A rotating helical focuser with a laser-etched scale is integrated into the corrector, so you can set and repeat its spacing precisely. Supplied adapters connect cameras by T2 (M42 × 0.75) or M48 × 0.75 thread.
The 2-inch barrel, approximately 85 mm long, fits almost all 2-inch focusers. For visual use, your focuser needs at least 32 mm of spare inward travel. For photography, the focus point moves about 35 mm outward. Explore Scientific publishes a separate dimension and spacing sheet for setting up camera distance.
| Manufacturer item number | 0510330 (current Bresser product number 14285) |
|---|---|
| EAN | 4007922005324 |
| Telescope type | Newtonian |
| Lens design | Four elements |
| Corrects | Coma, field curvature and astigmatism |
| Fastest focal ratio | f/3 |
| Focal length change | Approximately +6% (×1.06) |
| Usable field | 30 mm diameter |
| Visual polychromatic Strehl | 0.98 at f/4; 0.96 at f/3 (flat field, no refocusing) |
| Barrel | 2-inch, approximately 85 mm long |
|---|---|
| Focuser | Integrated rotating helical focuser with laser-etched scale |
| Camera adapters | T2 (M42 × 0.75) and M48 × 0.75 |
| Visual inward travel required | At least 32 mm |
| Photographic focus shift | About 35 mm outward |
| Material and colour | Aluminium; black |
| Manufacturer warranty | 10 years |
Explore Scientific HR Coma Corrector product page, with manuals and dimension/spacing sheet
Newtonian telescopes down to f/3, 2-inch focuser. Needs at least 32 mm spare inward travel for visual use; focus moves about 35 mm outward for imaging. Camera spacing per the manufacturer dimension/spacing sheet on the product page. Weight not published.
| Current product number | 14285 |
|---|---|
| Telescope type | Newtonian |
| Corrects | Coma, field curvature, astigmatism |
| Fastest focal ratio | f/3 |
| Focal length multiplier | 1.06 |
| Usable field (mm) | 30 |
| Visual polystrehl | 0.98 at f/4; 0.96 at f/3 (flat field, no refocusing) |
| Barrel | 2-inch, approx. 85 mm long |
| Integrated focuser | Rotating helical focuser with laser-etched scale |
| Minimum visual inward travel (mm) | 32 |
| Photographic focus shift outward (mm) | 35 |
| Material colour | Aluminium; black |
| Warranty years | 10 |
Data sheet
Specific References
Explore Scientific HR Coma Corrector — 2-inch high-resolution corrector for fast Newtonians The Explore Scientific HR Coma Corrector (item 0510330) is a four-lens, 2-inch corrector for Newtonian telescopes. It corrects coma, field curvature and astigmatism, and Explore Scientific specifies it for very fast systems down to f/3.
Manufacturer model: EXPLORE SCIENTIFIC HR Coma Corrector (0510330) · Specifications checked against manufacturer data on 2026-11-03
