telescopecomparison · 2-way
Askar FRA500 vs Askar 151PHQ
Askar
151PHQ
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
Key differences
-53% focal length
-40% aperture
Faster by 1.4 f-stops
Specifications
| Specification | Askar FRA500 | Askar 151PHQ |
|---|---|---|
| Optics | ||
| Type | Refractor | refractor |
| Optical design | Petzval Quintuplet APO | Petzval quintuplet FPL-51 |
| Aperture | 90mm | 151mm |
| Focal length | 500mm | 1057mm |
| Native f/ratio | f/5.6 | f/7.0 |
| Image circle | 60mm | 60mm |
| Full-frame support | Yes | Yes |
| Physical | ||
| Weight | 5.4kg | 15.5kg |
Advantages of Askar FRA500
- Wider field — 500mm vs 1057mm focal length
- Faster optics at f/5.6 vs f/7
- Lighter (5.4kg vs 15.5kg) — easier to travel with
Advantages of Askar 151PHQ
- Tighter framing — 1057mm vs 500mm focal length
- 68% more light-gathering aperture
Best for — Askar FRA500
- Large emission nebulae and star clusters
- Full-frame astro cameras and DSLRs
Best for — Askar 151PHQ
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
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 151PHQ — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 1.95° × 1.30°Scale: 0.73"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.27° × 0.85°Scale: 0.73"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.61° × 0.61°Scale: 0.73"/px
Askar FRA500 — recommended user
Best suited for beginners and wide-field enthusiasts running a backyard imaging setup.
Askar 151PHQ — recommended user
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.