telescopecomparison · 2-way
Celestron EdgeHD 8 vs TS-Optics UNC 254 f/4 Newtonian Astrograph
Celestron
EdgeHD 8
Best suited for experienced imagers chasing detail running a backyard imaging setup.
TS-Optics
UNC 254 f/4 Newtonian Astrograph
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
Key differences
+100% focal length
-20% aperture
Slower by 6.0 f-stops
Specifications
| Specification | Celestron EdgeHD 8 | TS-Optics UNC 254 f/4 Newtonian Astrograph |
|---|---|---|
| Optics | ||
| Type | SCT | newtonian |
| Optical design | Aplanatic SCT | Newtonian astrograph |
| Aperture | 203mm | 254mm |
| Focal length | 2032mm | 1016mm |
| Native f/ratio | f/10.0 | f/4.0 |
| Image circle | 42mm | — |
| Full-frame support | Yes | Yes |
| Physical | ||
| Weight | 6.4kg | 14.0kg |
Advantages of Celestron EdgeHD 8
- Tighter framing — 2032mm vs 1016mm focal length
- Larger image circle (42mm) — supports bigger sensors
- Lighter (6.4kg vs 14kg) — easier to travel with
Advantages of TS-Optics UNC 254 f/4 Newtonian Astrograph
- Wider field — 1016mm vs 2032mm focal length
- 25% more light-gathering aperture
- Faster optics at f/4 vs f/10
Best for — Celestron EdgeHD 8
- 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 — 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
Celestron EdgeHD 8 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 1.02° × 0.68°Scale: 0.38"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 0.66° × 0.44°Scale: 0.38"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.32° × 0.32°Scale: 0.38"/px
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
Celestron EdgeHD 8 — recommended user
Best suited for experienced imagers chasing detail running a backyard imaging setup.
TS-Optics UNC 254 f/4 Newtonian Astrograph — recommended user
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.