telescopecomparison · 2-way
Celestron C6 SCT vs William Optics FLT 120
William Optics
FLT 120
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Key differences
+92% focal length
+25% aperture
Slower by 3.5 f-stops
Specifications
| Specification | Celestron C6 SCT | William Optics FLT 120 |
|---|---|---|
| Optics | ||
| Type | sct | Refractor |
| Optical design | Schmidt-Cassegrain | Triplet APO |
| Aperture | 150mm | 120mm |
| Focal length | 1500mm | 780mm |
| Native f/ratio | f/10.0 | f/6.5 |
| Image circle | — | 44mm |
| Full-frame support | No | Yes |
| Physical | ||
| Weight | 4.5kg | 7.7kg |
Advantages of Celestron C6 SCT
- Tighter framing — 1500mm vs 780mm focal length
- 25% more light-gathering aperture
- Lighter (4.5kg vs 7.7kg) — easier to travel with
Advantages of William Optics FLT 120
- Wider field — 780mm vs 1500mm focal length
- Faster optics at f/6.5 vs f/10
- Larger image circle (44mm) — supports bigger sensors
Best for — Celestron C6 SCT
- Small galaxies, planetary nebulae, lunar & planetary detail
- High-resolution long-exposure work
Best for — William Optics FLT 120
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
Celestron C6 SCT — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 1.38° × 0.92°Scale: 0.52"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 0.90° × 0.60°Scale: 0.52"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.43° × 0.43°Scale: 0.52"/px
William Optics FLT 120 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 2.64° × 1.76°Scale: 0.99"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.73° × 1.15°Scale: 0.99"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.83° × 0.83°Scale: 0.99"/px
Celestron C6 SCT — recommended user
Best suited for experienced imagers chasing detail running a portable travel rig.
William Optics FLT 120 — recommended user
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
