telescopecomparison · 2-way
TS-Optics UNC 254 f/4 Newtonian Astrograph vs Askar 151PHQ
TS-Optics
UNC 254 f/4 Newtonian Astrograph
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
Askar
151PHQ
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
Key differences
+68% aperture
Faster by 3.0 f-stops
Specifications
| Specification | TS-Optics UNC 254 f/4 Newtonian Astrograph | Askar 151PHQ |
|---|---|---|
| Optics | ||
| Type | newtonian | refractor |
| Optical design | Newtonian astrograph | Petzval quintuplet FPL-51 |
| Aperture | 254mm | 151mm |
| Focal length | 1016mm | 1057mm |
| Native f/ratio | f/4.0 | f/7.0 |
| Image circle | — | 60mm |
| Full-frame support | Yes | Yes |
| Physical | ||
| Weight | 14.0kg | 15.5kg |
Advantages of TS-Optics UNC 254 f/4 Newtonian Astrograph
- 68% more light-gathering aperture
- Faster optics at f/4 vs f/7
Advantages of Askar 151PHQ
- Larger image circle (60mm) — supports bigger sensors
Best for — TS-Optics UNC 254 f/4 Newtonian Astrograph
- 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 — Askar 151PHQ
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
TS-Optics UNC 254 f/4 Newtonian Astrograph — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 2.03° × 1.35°Scale: 0.76"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.33° × 0.89°Scale: 0.76"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.64° × 0.64°Scale: 0.76"/px
Askar 151PHQ — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 1.95° × 1.30°Scale: 0.73"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.27° × 0.85°Scale: 0.73"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.61° × 0.61°Scale: 0.73"/px
TS-Optics UNC 254 f/4 Newtonian Astrograph — recommended user
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
Askar 151PHQ — recommended user
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
