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FAQ: Products
How does it work? Why choose a Newise?
An elegant design with a performance to match:
You will have seen that the Newise design is impressive on paper, but how does it
perform on the sky? In short: beautifully — but don't just take our word for it! You
can read independent reviews from the astronomical press by following these links:
Astronomy Now — BBC Sky
at Night magazine.
Dr Ian Morison of Jodrell Bank Observatory teaches astronomy at the University of
Manchester, delivers lectures on telescope optics, and has co-authored two astronomy
books for amateurs both including chapters on choosing and using telescopes. Dr Morison
also reviewed the Newise 200X and his full online appraisal may be read
here.
At star parties and other gatherings where the Newise telescope has been demonstrated,
many have expressed surprise at how the instrument is able to outperform other 'scopes
— many of larger aperture — on planetary detail. And the wide-angle, flat
and aberration-free views of nebulae just have to be seen to be believed!
 At Newise Technologies Ltd. we acknowledge that many people also wish to use their 'scopes for
imaging with CCD or film. That is why we designed the Newise to be a photo-visual
instrument from the ground up. You can see the stunning results produced by users of our
'scopes in the Gallery, but let us show you how good it gets.
In the graph shown right, the performance curve of a theoretically perfect telescope
would have a RMS spot size smaller than the diffraction limit over all field
sizes. In the real world, if more of the performance curve lies lies below the
diffraction limit the better. What is dramatically evident by comparing the Newise to its
principal competitors, is that it has a diffraction-limited spot size over a
one degree-wide field and a considerably smaller spot size over wider fields
of view. The spot size performance of various Newise apertures is tabulated below:
| Spot size in microns (µ = 0.001mm) for various Newise apertures and distances from the optical axis |
| Aperture |
200mm |
300mm |
400mm |
500mm |
1 metre |
| Diffraction limit |
4.1µ |
3.6µ |
3.4µ |
2.9µ |
2.9µ |
| Distance from optical axis |
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| 0.0° |
2.8µ |
2.4µ |
2.9µ |
1.6µ |
2.7µ |
| 0.2° |
3.0µ |
3.2µ |
3.9µ |
2.4µ |
4.6µ |
| 0.4° |
3.4µ |
4.2µ |
6.4µ |
3.8µ |
6.8µ |
| 0.6° |
3.6µ |
4.6µ |
8.2µ |
4.9µ |
8.5µ |
| 0.8° |
3.4µ |
5.1µ |
8.8µ |
4.9µ |
8.4µ |
| 1.0° |
3.9µ (20.0mm) |
6.7µ (34.2mm) |
9.9µ (33.2mm) |
4.2µ (35.4mm) |
6.8µ (69.8mm) |
| 1.2° |
6.8µ |
9.5µ |
14.3µ |
8.0µ |
19.5µ |
| 1.4° |
10.0µ |
15.7µ |
46.7µ |
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| 1.6° |
15.7µ |
37.3µ |
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| 1.8° |
25.8µ |
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| 2.0° |
47.4µ |
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In conclusion, a 200mm f/6 Newise is quite capable of delivering a flat and essentially
aberration-free 2 degree-wide field of view that will show, perhaps for the first time,
what your premium eyepieces are capable of. Just to remind you what a 2 degree field of
view is like, take a look at the examples below. In each, the inner dotted circle
represents the 1 degree field of competing instruments. Do also bear in mind that a 2 degree
field shows you four times the area of a 1 degree view!
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| The Pleiades |
The Orion Nebula |
Perseus Double Cluster |
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