telescopecomparison · 2-way
Explore Scientific ED127 FCD-100 vs Astro-Tech AT115EDT

Explore Scientific
ED127 FCD-100
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.

Astro-Tech
AT115EDT
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Key differences
+18% focal length
+10% aperture
Slower by 0.5 f-stops
Specifications
| Specification | Explore Scientific ED127 FCD-100 | Astro-Tech AT115EDT |
|---|---|---|
| Optics | ||
| Type | Refractor | refractor |
| Optical design | Triplet APO | Apo triplet FPL-53 |
| Aperture | 127mm | 115mm |
| Focal length | 952mm | 805mm |
| Native f/ratio | f/7.5 | f/7.0 |
| Image circle | 40mm | 52mm |
| Full-frame support | Yes | Yes |
| Physical | ||
| Weight | 8.6kg | 6.6kg |
Advantages of Explore Scientific ED127 FCD-100
- Tighter framing — 952mm vs 805mm focal length
- 10% more light-gathering aperture
Advantages of Astro-Tech AT115EDT
- Wider field — 805mm vs 952mm focal length
- Faster optics at f/7 vs f/7.5
- Larger image circle (52mm) — supports bigger sensors
- Lighter (6.6kg vs 8.6kg) — easier to travel with
Best for — Explore Scientific ED127 FCD-100
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
Best for — Astro-Tech AT115EDT
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
Explore Scientific ED127 FCD-100 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 2.17° × 1.44°Scale: 0.81"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.41° × 0.94°Scale: 0.81"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.68° × 0.68°Scale: 0.81"/px
Astro-Tech AT115EDT — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 2.56° × 1.71°Scale: 0.96"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.67° × 1.12°Scale: 0.96"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.80° × 0.80°Scale: 0.96"/px
Explore Scientific ED127 FCD-100 — recommended user
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Astro-Tech AT115EDT — recommended user
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
