ED refractorOptical tube onlySky-Watcher
A 72 mm f/5.8 ED doublet that has become the default first astrograph — small, light, well corrected for its price, and honest about needing a flattener.
The most sensible entry into wide-field deep-sky imaging, provided you budget for the flattener it does not include.
Sold as an optical tube only. No mount, tripod or head is included. For imaging in particular, the mount is usually the larger part of the total cost.
Where to buy
Links open at the retailer in a new tab. We do not publish prices, because a price we recorded last month is worse than no price at all.
The same four purposes are scored for every telescope on this site, using the same weights. A telescope that is excellent for one is often poor for another — that is the point.
Visual observing
5.7 / 10
Confidence: medium
Sharp and colour-clean for its size, but 72 mm is a small aperture and this is a supplementary visual instrument rather than a main one.
| Factor | Score | Weight |
|---|---|---|
| Aperture | 2.3 | 30% |
| Optical qualityeditorial | 7.5 | 20% |
| Ergonomicseditorial | 7.0 | 15% |
| Portability | 9.7 | 15% |
| Mount usabilitySold without a mount — the mount is a separate purchase and a separate decision. | 2.0 | 10% |
| Valueeditorial | 8.5 | 10% |
Weighted total: 5.7. Read the full methodology.
Nebula imaging
6.5 / 10
Confidence: high
Focal length, weight and correction all land in the right place for large nebulae; only the required flattener and modest aperture hold it back.
| Factor | Score | Weight |
|---|---|---|
| Focal ratio | 4.1 | 25% |
| Corrected field | 5.0 | 20% |
| Image circleImage circle not published; rated from stated APS-C support. | 7.0 | 15% |
| Focal length fit | 10.0 | 15% |
| Mount demand | 7.7 | 10% |
| Imaging workfloweditorial | 7.0 | 10% |
| Valueeditorial | 8.5 | 5% |
Weighted total: 6.5. Read the full methodology.
Galaxy imaging
5.4 / 10
Confidence: high
At 420 mm the image scale is far too coarse for anything but the largest nearby galaxies.
| Factor | Score | Weight |
|---|---|---|
| Focal length fit | 4.5 | 25% |
| Resolving power | 2.3 | 20% |
| Corrected field | 5.0 | 15% |
| Optical qualityeditorial | 7.5 | 15% |
| Mount demand | 7.7 | 10% |
| Imaging workfloweditorial | 7.0 | 10% |
| Valueeditorial | 8.5 | 5% |
Weighted total: 5.4. Read the full methodology.
Planetary imaging
4.1 / 10
Confidence: high
Aperture and focal length are both far below what planetary work needs, and no amount of amplification substitutes for either.
| Factor | Score | Weight |
|---|---|---|
| Aperture | 2.3 | 30% |
| Focal length fit | 0.0 | 25% |
| Optical qualityeditorial | 7.5 | 20% |
| Collimation & thermals | 10.0 | 10% |
| TrackingNo mount supplied — tracking quality depends entirely on the mount you pair it with. | 5.0 | 10% |
| Valueeditorial | 8.5 | 5% |
Weighted total: 4.1. Read the full methodology.
Scores are relative to every telescope on this site, not absolute quality marks. A 6.5 for galaxy imaging and a 6.5 for visual observing do not mean the same thing. How scoring works.
A two-element air-spaced design with one extra-low-dispersion element. That single ED element does most of the work an apochromatic triplet does, at a fraction of the cost, leaving a faint violet halo visible only around the very brightest stars and the lunar limb.
At f/5.8 the field is curved, as it is on essentially every doublet. Sky-Watcher sells a matched flattener and a 0.85× reducer/flattener; one of them is not optional if you intend to photograph anything.
Used with a diagonal and good eyepieces this is a pleasant, sharp, low-maintenance grab-and-go. It frames the Pleiades beautifully and shows the Orion Nebula’s shape well. It will not compete with a 200 mm reflector on anything faint — 72 mm is 72 mm — but it is genuinely enjoyable rather than merely tolerable, which is not true of every small refractor.
This is what the telescope is for. With the reducer fitted the system runs near f/4.9 at roughly 357 mm, which frames the North America Nebula, the Heart and Soul complex, and the Veil comfortably on an APS-C sensor. Stars stay tight across the frame once spacing is correct.
The limiting factor is aperture, not correction: 72 mm collects modest light, so plan on hours of integration rather than minutes. The upside is that a small tracking mount can carry it with a guide scope and still have payload margin, and mount margin is what actually determines whether a beginner’s images come out round.
420 mm renders most galaxies as small, soft ovals. Andromeda, the Triangulum Galaxy and a handful of other large nearby systems work well; anything in the Virgo cluster does not. Treat galaxy imaging as an occasional bonus here, not a capability.
Not a planetary instrument in any configuration. The aperture caps resolution well below what planetary imaging demands, and reaching a usable focal ratio would require amplification that simply magnifies a soft image.
Under two kilograms with the rings on, 335 mm long with the dew shield retracted, and completely maintenance-free. It fits in hand luggage. The real setup complexity lives in the spacing between flattener and sensor, which has to be measured once and then left alone.
| Aperture | 72 mm (2.8") |
|---|---|
| Focal length | 420 mm (16.5") |
| Focal ratio | f/5.8 |
| Optical design | Air-spaced ED doublet |
| Type | ED refractor |
| Glass / mirror | One extra-low-dispersion element, fully multi-coated |
| Resolving power | 1.61"Calculated from aperture (Dawes limit), not a manufacturer figure. |
| Limiting magnitude | ≈ 11.3Estimated from aperture under dark skies. Real skies are usually worse. |
| Backfocus | 55 mm |
|---|---|
| Field correction built in | No |
| Usable visually | Yes |
| APS-C sensors | Supported |
| Full-frame sensors | Not fully covered |
| Reducer | Available (×0.85) |
| Corrector required | Yes — sold separately |
| Autoguiding | Recommended |
| Mount included | No — optical tube only |
|---|---|
| Tracking | Depends on your mount |
| GoTo | Depends on your mount |
| Mounting interface | Vixen-style dovetail |
| OTA weight | 1.9 kg (4.2 lb) |
|---|---|
| Tube length | 335 mm (13.2") |
| Tube diameter | 90 mm |
| Longest transport dimension | 430 mm (16.9") |
| Brand | Sky-Watcher |
|---|---|
| Model | Evostar 72ED |
| Status | Current |
| Price band | Mid-rangeWe publish bands, not prices. Check the retailer for the current price. |
| Skill level | beginner, intermediate |
We list an accessory as included only when the product record says so explicitly. If a mount, eyepiece, camera, flattener, reducer, corrector, guider or adapter is not listed above, assume it is not in the box.
Petzval refractorCamera onlyOTA only
A tiny, expensive, almost foolproof wide-field astrograph. You are paying for the fact that nothing about the optical train can go wrong.
Apochromatic refractorOTA only
The classic do-everything four-inch apo: excellent visually, capable on nebulae with a flattener, and never the cheapest way to any single goal.
Achromatic refractorOTA only
A cheap, light, genuinely fun rich-field refractor for sweeping the Milky Way, badly miscast as a planetary or imaging telescope.