telescopecomparison · 2-way
Askar FRA400 vs Askar FRA500
Key differences
-20% focal length
-20% aperture
Specifications
| Specification | Askar FRA400 | Askar FRA500 |
|---|---|---|
| Optics | ||
| Type | Refractor | Refractor |
| Optical design | Petzval Quintuplet APO | Petzval Quintuplet APO |
| Aperture | 72mm | 90mm |
| Focal length | 400mm | 500mm |
| Native f/ratio | f/5.6 | f/5.6 |
| Image circle | 44mm | 60mm |
| Full-frame support | Yes | Yes |
| Physical | ||
| Weight | 3.9kg | 5.4kg |
Advantages of Askar FRA400
- Wider field — 400mm vs 500mm focal length
- Lighter (3.9kg vs 5.4kg) — easier to travel with
Advantages of Askar FRA500
- Tighter framing — 500mm vs 400mm focal length
- 25% more light-gathering aperture
- Larger image circle (60mm) — supports bigger sensors
Best for — Askar FRA400
- Large emission nebulae and star clusters
- Full-frame astro cameras and DSLRs
Best for — Askar FRA500
- Large emission nebulae and star clusters
- Full-frame astro cameras and DSLRs
Askar FRA400 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 5.16° × 3.44°Scale: 1.94"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 3.37° × 2.25°Scale: 1.94"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.62° × 1.62°Scale: 1.94"/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 FRA400 — recommended user
Best suited for beginners and wide-field enthusiasts running a portable travel rig.
Askar FRA500 — recommended user
Best suited for beginners and wide-field enthusiasts running a backyard imaging setup.