telescopecomparison · 2-way
Askar 120APO vs Askar FRA500
Askar
120APO
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Key differences
+68% focal length
+33% aperture
Slower by 1.4 f-stops
Specifications
| Specification | Askar 120APO | Askar FRA500 |
|---|---|---|
| Optics | ||
| Type | Refractor | Refractor |
| Optical design | Triplet APO | Petzval Quintuplet APO |
| Aperture | 120mm | 90mm |
| Focal length | 840mm | 500mm |
| Native f/ratio | f/7.0 | f/5.6 |
| Image circle | 44mm | 60mm |
| Full-frame support | Yes | Yes |
| Physical | ||
| Weight | 8.5kg | 5.4kg |
Advantages of Askar 120APO
- Tighter framing — 840mm vs 500mm focal length
- 33% more light-gathering aperture
Advantages of Askar FRA500
- Wider field — 500mm vs 840mm focal length
- Faster optics at f/5.6 vs f/7
- Larger image circle (60mm) — supports bigger sensors
- Lighter (5.4kg vs 8.5kg) — easier to travel with
Best for — Askar 120APO
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
Best for — Askar FRA500
- Large emission nebulae and star clusters
- Full-frame astro cameras and DSLRs
Askar 120APO — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 2.46° × 1.64°Scale: 0.92"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.60° × 1.07°Scale: 0.92"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.77° × 0.77°Scale: 0.92"/px
Askar FRA500 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 4.13° × 2.75°Scale: 1.55"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 2.69° × 1.80°Scale: 1.55"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.29° × 1.29°Scale: 1.55"/px
Askar 120APO — recommended user
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Askar FRA500 — recommended user
Best suited for beginners and wide-field enthusiasts running a backyard imaging setup.