telescopecomparison · 2-way
Unistellar eVscope 2 vs William Optics GT 81
Unistellar
eVscope 2
Best suited for beginners and wide-field enthusiasts running a backyard imaging setup.
William Optics
GT 81
Best suited for beginners and wide-field enthusiasts running a portable travel rig.
Key differences
-6% focal length
+41% aperture
Faster by 2.0 f-stops
Specifications
| Specification | Unistellar eVscope 2 | William Optics GT 81 |
|---|---|---|
| Optics | ||
| Type | smart-telescope | refractor |
| Optical design | Newtonian all-in-one | Apo triplet FPL-53 |
| Aperture | 114mm | 81mm |
| Focal length | 450mm | 478mm |
| Native f/ratio | f/3.9 | f/5.9 |
| Image circle | — | 44mm |
| Full-frame support | No | Yes |
| Physical | ||
| Weight | 9.0kg | 3.8kg |
Advantages of Unistellar eVscope 2
- 41% more light-gathering aperture
- Faster optics at f/3.9 vs f/5.9
Advantages of William Optics GT 81
- Larger image circle (44mm) — supports bigger sensors
- Lighter (3.8kg vs 9kg) — easier to travel with
Best for — Unistellar eVscope 2
- Large emission nebulae and star clusters
- Fast imaging — short exposures per sub
Best for — William Optics GT 81
- Large emission nebulae and star clusters
- Full-frame astro cameras and DSLRs
Unistellar eVscope 2 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 4.58° × 3.06°Scale: 1.72"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 2.99° × 2.00°Scale: 1.72"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.44° × 1.44°Scale: 1.72"/px
William Optics GT 81 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 4.32° × 2.88°Scale: 1.62"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 2.82° × 1.88°Scale: 1.62"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.35° × 1.35°Scale: 1.62"/px
Unistellar eVscope 2 — recommended user
Best suited for beginners and wide-field enthusiasts running a backyard imaging setup.
William Optics GT 81 — recommended user
Best suited for beginners and wide-field enthusiasts running a portable travel rig.