telescopecomparison · 2-way
Askar 107PHQ vs Borg 90FL
Askar
107PHQ
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Key differences
+50% focal length
+19% aperture
Slower by 1.4 f-stops
Specifications
| Specification | Askar 107PHQ | Borg 90FL |
|---|---|---|
| Optics | ||
| Type | refractor | refractor |
| Optical design | Petzval quintuplet FPL-51 | Apo doublet fluorite |
| Aperture | 107mm | 90mm |
| Focal length | 749mm | 500mm |
| Native f/ratio | f/7.0 | f/5.6 |
| Image circle | 44mm | — |
| Full-frame support | Yes | No |
| Physical | ||
| Weight | 7.5kg | 2.5kg |
Advantages of Askar 107PHQ
- Tighter framing — 749mm vs 500mm focal length
- 19% more light-gathering aperture
- Larger image circle (43.9mm) — supports bigger sensors
Advantages of Borg 90FL
- Wider field — 500mm vs 749mm focal length
- Faster optics at f/5.6 vs f/7
- Lighter (2.5kg vs 7.5kg) — easier to travel with
Best for — Askar 107PHQ
- Medium-sized galaxies and planetary nebulae
- Full-frame astro cameras and DSLRs
Best for — Borg 90FL
- Large emission nebulae and star clusters
Askar 107PHQ — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 2.75° × 1.84°Scale: 1.04"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 1.80° × 1.20°Scale: 1.04"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 0.86° × 0.86°Scale: 1.04"/px
Borg 90FL — 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 107PHQ — recommended user
Best suited for intermediate imagers building a versatile kit running a backyard imaging setup.
Borg 90FL — recommended user
Best suited for beginners and wide-field enthusiasts running a portable travel rig.