Best Refractor Telescopes for Astrophotography

At a Glance

• Choose your mount first, since it decides which scopes you can use.
• Apochromatic (APO/ED) optics keep stars tight and neutral in photos.
• The RedCat 51 is the easy wide-field choice. The Askar 71F suits a stronger mount and more reach.
• The Evostar 72ED is the lower-cost route, but it needs a flattener.
• Budget for the whole setup, not just the tube.

The quick answer: which refractor should you buy?

The best refractor telescopes for astrophotography are usually short, fast apochromatic scopes in the 50-80mm aperture range. They work like a telephoto lens, so they suit people moving up from camera lenses. Here are the picks by goal:

• Wide-field and portable: William Optics RedCat 51 WIFD (Gen3)
• Balanced all-rounder: Askar 71F
• Budget entry: Sky-Watcher Evostar 72ED
• More aperture, also good for viewing: Sky-Watcher Evostar 80ED
• Light travel rig on a budget: William Optics ZenithStar 61II

Tip: The scope is only one part of the setup. A sturdy tracking mount matters just as much, and the camera and accessories add to the bill.

The picks, a mount section and a comparison table follow.

What actually matters in an astrophotography refractor

• Apochromatic (APO/ED) optics vs. achromats. An achromat focuses colors at slightly different points, and in photos that shows up as blue or purple halos around bright stars. APO and ED designs use special glass to keep colors together. Stars stay tight and neutral.
• Focal length and focal ratio. Shorter focal length gives a wider field, which suits big nebulae. A lower f-ratio gathers light faster, so you need shorter exposures. Short scopes also forgive small tracking errors better than long ones.
• Flat field. Many scopes show stars stretched or bent toward the corners, and a flattener fixes that. Some designs have the correction built in, while others need an add-on.
• Weight and size vs. your mount. A scope that's too heavy for your mount gives you trailed stars and frustration. Check the mount's rated payload, and remember your camera and accessories add weight.
• Focuser quality and sensor coverage. A solid focuser holds a heavy camera without sagging. Make sure the scope's image circle covers your camera's sensor, since a small-sensor astro camera is easier to cover than a full-frame one.
• Aperture vs. portability. More aperture collects more light and resolves more detail. It also brings more weight, a costlier mount and a bigger case.

Types of refractor setups: Petzval, triplet, doublet and quadruplet

Doublet ED scopes use two lens elements. They're lighter and cheaper, but they usually need a separate flattener for sharp corners. The Evostar 72ED, Evostar 80ED and ZenithStar 61II fit here.

Petzval and flat-field designs build field correction into the optical tube, so you skip buying a flattener and fussing with its spacing. The RedCat 51 is a quadruplet Petzval, and the Askar 71F is a four-element flat-field design. Both are compact and simple to set up.

Larger quadruplet astrographs have a bigger imaging circle, but they're heavier and cost more. None of our picks are in that class. If you outgrow a 71-80mm scope, that's the next category to research.

Triplets use three elements and are common among premium APO scopes. We list none here, so treat them as a step-up option.

Manufacturers revise their scopes. Check the current spec sheet for exact focal length, weight, backfocus and image circle before you buy.

Our top refractor picks for astrophotography

Tip: Choose by your mount first, then by the targets you want.

If you have a light star tracker, look at the smaller scopes. If you have a small equatorial mount, the larger scopes open up.

1. William Optics RedCat 51 WIFD (Gen3)

Best for: first wide-field deep-sky imaging with a light, portable rig

Suits beginners who want a light, portable rig for wide-field deep-sky imaging. Its built-in field correction means no separate flattener is needed, but it is not suited to small galaxies.

What we like:

• Flat stars to the corners with little setup fuss
• Very light and portable
• Wide field fits large nebulae such as North America in one frame

Keep in mind:

• Small aperture and short focal length, so it is not suited to small galaxies
• A forum owner says price-to-performance is weaker than Askar scopes

Check price on Amazon

2. Askar 71F

Best for: a versatile, full-frame-capable refractor at a fair price

Suits imagers who want a versatile, full-frame-capable scope at a fair price. At about 7 lb, it is too heavy for very light mounts such as the Sky-Watcher Star Adventurer GTi.

What we like:

• Simple setup with good edge-to-edge correction
• Works with many cameras and mounts
• Strong image quality for the price

Keep in mind:

• About 7 lb, which is too heavy for very light mounts such as the Sky-Watcher Star Adventurer GTi
• Reducer is an optional extra

Check price on Amazon

3. Sky-Watcher Evostar 72ED

Best for: a beginner who wants one scope for visual use and imaging

Suits beginners who want one scope for both eyepiece viewing and imaging. It needs a separate flattener or reducer for the best corner stars and a tracking mount such as the Star Adventurer 2i.

What we like:

• Works for both eyepiece viewing and imaging
• Moderate cost for a long-term imaging tool

Keep in mind:

• Needs a separate field flattener or reducer for best corner stars
• Needs a tracking mount for long exposures

Check price on Amazon

4. Sky-Watcher Evostar 80ED

Best for: beginner to intermediate imagers who want more aperture

Suits beginner to intermediate imagers who want more aperture and a dependable, dual-purpose scope for visual use and imaging. The flattener is sold separately and is needed for imaging.

What we like:

• Seen as a top apochromatic pick for beginner and intermediate imagers
• Dual-purpose design

Keep in mind:

• Flattener is sold separately and is needed for imaging

Check price on Amazon

5. William Optics ZenithStar 61II

Best for: travel and nebula imaging on a lighter budget

Suits travelers and imagers on a lighter budget who want nebula photos from a scope under 3 lb. Its small aperture limits fine detail.

What we like:

• Light and good for travel
• Well suited to nebula imaging

Keep in mind:

• Small aperture limits fine detail

Check price on Amazon

Spec lines

Figures come from manufacturer information where we have it. "Check spec sheet" means we have no verified figure to quote.

Choosing between similar scopes

Evostar 72ED vs. 80ED

• Choose the 72ED for a lighter, easier load on a tracker such as the Star Adventurer 2i.
• Choose the 80ED for more aperture, paired with a sturdier mount. Both need a separate flattener for imaging.

RedCat 51 vs. Askar 71F

• Choose the RedCat 51 if portability and the widest field matter most. It fits large nebulae such as North America in one frame and weighs about 3.2 lb.
• Choose the Askar 71F for a longer focal length, full-frame capability and a better balance of reach and field. It weighs about 7 lb, so it needs a stronger mount.

ZenithStar 61II vs. Askar 71F

• Choose the ZenithStar if weight and travel come first and you accept less fine detail. It is under 3 lb.
• Choose the 71F if you want built-in flat-field correction and don't mind carrying and mounting a heavier scope.

The 71F's price is fair for what it delivers, but it isn't the lightest or cheapest scope here. "Fair price" means good value for a flat-field scope, not a budget pick. The Evostar 72ED is the lower-cost entry, with a flattener added later.

Which scope for which kind of imaging?

For camera type, a dedicated astro camera is usually lighter and easier to cool and control. A DSLR or mirrorless camera works well too, and many beginners start with one they already own.

Mount tiers: what carries what

Check each mount's current rated payload on the maker's page. We don't quote capacity numbers here because ratings and listings vary. Leave a safety margin, since your camera, rings and guide scope all add weight.

Tier 1: star trackers (for example, the Sky-Watcher Star Adventurer 2i)

• Best for: the RedCat 51 and ZenithStar 61II, plus the Evostar 72ED on a tracker such as the 2i.
• Strength: portable and simple.
• Limit: long exposures are unforgiving with heavier or longer scopes.

Tier 2: light GoTo trackers (for example, the Star Adventurer GTi)

• Best for: the RedCat 51 and the lightest builds.
• The Askar 71F is too heavy for the GTi at about 7 lb.

Tier 3: a small equatorial mount

• Best for: the Askar 71F and the Evostar 80ED, and also the lighter scopes if you want room to grow.
• Strength: steadier tracking and room for a guide scope and camera.
• Limit: heavier, and it needs a power source.

What else you need besides the telescope

• A tracking mount. Star tracker or small equatorial, with a payload margin.
• A camera and adapters. You need the right T-ring or adapter for your camera. Spacing matters, so check backfocus requirements.
• A flattener or reducer where needed. The Evostar scopes need a flattener. The ZenithStar is a doublet, so plan on one. The 71F's reducer is optional.
• Guiding. You can start unguided on short scopes. Add a guide scope and camera when longer exposures show trailed stars.
• Power, dew control and polar alignment. A portable power supply, a dew heater strap and a method for polar alignment are common needs.
• Solar safety. Never point a scope or camera at the Sun without a proper commercial solar filter on the front. Imaging without protection can damage equipment and your eyes.

A realistic note on total cost

The scope is often only part of the total. A mount, a camera, a flattener or adapters, power and a guiding setup can match or exceed the scope's cost. A budget scope like the Evostar 72ED looks cheap until you add a flattener and a tracker. A scope with built-in correction, like the RedCat 51, costs more up front but saves on accessories. Plan the whole chain before you buy.

Common mistakes beginners make

• Buying a scope before choosing a mount. The mount decides which scopes you can use.
• Choosing too much focal length. Longer scopes are harder to track, so start wide.
• Ignoring backfocus and spacing. Flatteners and cameras need exact distances, or corners suffer.
• Expecting planetary detail from a wide-field refractor. These scopes are for nebulae and star fields.
• Skipping a flattener on a scope that needs one. The Evostar and ZenithStar scopes benefit from one.
• Expecting polished images on the first night. Focus, alignment and processing take practice.

Frequently Asked Questions

Is a refractor or a reflector better for astrophotography?

Neither is better overall. Refractors are simple, sealed and need little adjustment, which suits beginners. Reflectors give more aperture for the money but need collimation and often a coma corrector.

Do I need an apochromatic refractor for astrophotography?

For good results, yes, it's the usual choice. APO and ED glass keeps color fringing around bright stars low. An ordinary achromat tends to show it in photos.

Can I use a DSLR or mirrorless camera with these refractors?

Yes, with the right adapter and correct spacing. The Askar 71F is full-frame capable. For the other scopes, check the image circle against your sensor size on the spec sheet.

What mount do I need for an astrophotography refractor?

You need a tracking mount. A star tracker suits the lightest scopes, such as the RedCat 51 and ZenithStar 61II. A small equatorial mount suits heavier ones like the Askar 71F, and you should always check payload with a margin.

Can a beginner use the same refractor for visual observing and imaging?

Yes. The Evostar 72ED and 80ED are both described as working for eyepiece viewing and imaging. The tradeoff is that you'll need a flattener and a tracking mount for imaging.

Do I need a field flattener or reducer?

It depends on the scope. The RedCat 51 and Askar 71F have field correction built in. The Evostar 72ED and 80ED need a separate flattener, and the doublet ZenithStar likely does too. A reducer is optional and shortens focal length for a wider field.

Bottom line

Start with your mount and camera, then pick the scope. The RedCat 51 is the easy wide-field choice. The Askar 71F suits people with a stronger mount who want more reach. The Evostar 72ED is the lower-cost route if you'll buy a flattener. Budget for the whole setup, not just the tube.