telescopecomparison · 2-way
Sky-Watcher Quattro 250P vs Astro-Physics 155mm f/6 StarFire CS

Sky-Watcher
Quattro 250P
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.

Astro-Physics
155mm f/6 StarFire CS
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Key differences
+8% focal length
+61% aperture
Faster by 2.0 f-stops
Specifications
| Specification | Sky-Watcher Quattro 250P | Astro-Physics 155mm f/6 StarFire CS |
|---|---|---|
| Optics | ||
| Type | newtonian | refractor |
| Optical design | Newtonian astrograph | Christen Superachromat (4-element) |
| Aperture | 250mm | 155mm |
| Focal length | 1000mm | 930mm |
| Native f/ratio | f/4.0 | f/6.0 |
| Image circle | — | 64mm |
| Full-frame support | Yes | Yes |
| Physical | ||
| Weight | 15.5kg | 10.9kg |
Advantages of Sky-Watcher Quattro 250P
- 61% more light-gathering aperture
- Faster optics at f/4 vs f/6
Advantages of Astro-Physics 155mm f/6 StarFire CS
- Larger image circle (64mm) — supports bigger sensors
- Lighter (10.9kg vs 15.5kg) — easier to travel with
Best for — Sky-Watcher Quattro 250P
- Medium-sized galaxies and planetary nebulae
- Fast imaging — short exposures per sub
- Faint-object imaging under dark skies
- Full-frame astro cameras and DSLRs
Best for — Astro-Physics 155mm f/6 StarFire CS
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
Sky-Watcher Quattro 250P — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 2.06° × 1.38°Scale: 0.78"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.35° × 0.90°Scale: 0.78"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.65° × 0.65°Scale: 0.78"/px
Astro-Physics 155mm f/6 StarFire CS — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 2.22° × 1.48°Scale: 0.83"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.45° × 0.97°Scale: 0.83"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.70° × 0.70°Scale: 0.83"/px
Sky-Watcher Quattro 250P — recommended user
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
Astro-Physics 155mm f/6 StarFire CS — recommended user
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.


