telescopecomparison · 2-way
Astro-Tech AT12RC vs Celestron C9.25 SCT
Astro-Tech
AT12RC
Best suited for experienced imagers chasing detail running a permanent observatory setup.
Celestron
C9.25 SCT
Best suited for experienced imagers chasing detail running a backyard imaging setup.
Key differences
+30% aperture
Faster by 2.0 f-stops
Specifications
| Specification | Astro-Tech AT12RC | Celestron C9.25 SCT |
|---|---|---|
| Optics | ||
| Type | ritchey-chretien | sct |
| Optical design | Truss Ritchey-Chrétien | Schmidt-Cassegrain |
| Aperture | 305mm | 235mm |
| Focal length | 2432mm | 2350mm |
| Native f/ratio | f/8.0 | f/10.0 |
| Image circle | — | — |
| Full-frame support | Yes | No |
| Physical | ||
| Weight | 26.5kg | 9.5kg |
Advantages of Astro-Tech AT12RC
- 30% more light-gathering aperture
- Faster optics at f/8 vs f/10
Advantages of Celestron C9.25 SCT
- Lighter (9.5kg vs 26.5kg) — easier to travel with
Best for — Astro-Tech AT12RC
- Small galaxies, planetary nebulae, lunar & planetary detail
- High-resolution long-exposure work
- Faint-object imaging under dark skies
- Full-frame astro cameras and DSLRs
Best for — Celestron C9.25 SCT
- Small galaxies, planetary nebulae, lunar & planetary detail
- High-resolution long-exposure work
- Faint-object imaging under dark skies
Astro-Tech AT12RC — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 0.85° × 0.57°Scale: 0.32"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 0.55° × 0.37°Scale: 0.32"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.27° × 0.27°Scale: 0.32"/px
Celestron C9.25 SCT — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 0.88° × 0.59°Scale: 0.33"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 0.57° × 0.38°Scale: 0.33"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.28° × 0.28°Scale: 0.33"/px
Astro-Tech AT12RC — recommended user
Best suited for experienced imagers chasing detail running a permanent observatory setup.
Celestron C9.25 SCT — recommended user
Best suited for experienced imagers chasing detail running a backyard imaging setup.