$Askar 71F Flat-Field Refractor — image 1$

Askar

Askar 71F Flat-Field Refractor

A 71mm ED doublet with a built-in flat field, sharp corners with no separate flattener, at a price that undercuts the triplets. A smart, simple first imaging refractor.

84/ 100

Polaris Score

#4 of 8 imaging APO refractors

See the breakdown ↓

Aperture

71mm

Focal Length

490mm

Focal Ratio

f/6.9

Mount Type

None (OTA only)

Optical Design

ED Doublet Refractor

Weight

2.3 kg

From$599

Lowest in 90 days

Price tracked by PolarisObserved 29 timesTracking since Jul 2026

Try in simulator →

Where to buy

Agena AstroProductsPartnerBest price$599→High Point Scientific$599→Starizona$659→

Verified 2h ago · prices tracked daily

What it's built forOpen these in the simulator →

This telescope was built for sweeping wide.

A short, fast refractor with a generous true field — the whole sword of Orion in one view, star fields that spill past the field stop. It rewards low power and dark skies far more than chasing magnification.

Widest true fieldsTack-sharp to the edge

The view people remember

Andromeda, wider than the Moon.

A vast soft oval with a blazing core — two and a half million light-years of galaxy, spilling well past the field of view under a genuinely dark sky.

See Andromeda Galaxy through this telescope →

Where else it shines

Needs patience

Orion Nebula

Bright core visible, outer wisps need patience and dark adaptation

Open view →

Easy first target

The Pleiades

Many cluster members resolved with color contrast between bright stars

Open view →

Rewards a dark sky

Whirlpool Galaxy

Faint elongated smudge — averted vision helps

Open view →

Also excellent on

Saturn

Small bright disk — featureless point at low magnification

Open view →

✦

Tight planetary detail belongs to a longer scope. This one trades reach for a breathtaking field.

01What it's good at

What it's best at — and the trade-offs.

Best at

✓A flat-field doublet gives corner-sharp stars without buying and spacing a flattener.

✓ED glass controls most false colour for clean, largely colour-free stars.

✓Light (2.3kg) and compact, ideal on a small tracker for wide-field imaging.

✓Priced below the triplets, so more budget is left for the mount and camera that matter.

Trade-offs

!A doublet leaves a faint colour trace on the very brightest stars versus a triplet.

!OTA only; a tracking mount and camera are extra.

!At f/6.9 it is a touch slower than the fast astrographs, so exposures run longer.

!71mm is a wide-field aperture, not a light bucket for faint small objects.

02In plain English

What These Numbers Mean

Aperture

71 mm

Under three inches of glass. It is enough for wide-field imaging and pleasant low-power views of clusters and the Moon, but faint galaxies and high-magnification planetary work are beyond what this size can deliver.

Focal length

490 mm

A widely useful wide field. Large nebulae like the North America, the Rosette and the Andromeda Galaxy fit an APS-C frame comfortably, which is exactly the target list most people start with.

Focal ratio

f/6.9

Middle speed. Exposures run a little longer than an f/5 astrograph needs, in exchange for gentler tolerances on focus, tilt and eyepiece quality. A sensible ratio for someone still learning the workflow.

Optical design

Flat-field ED refractor

The field flattening is designed in rather than bolted on, so stars stay round to the corners without a separate flattener and its spacing calculations. Fewer parts in the train means fewer things to get wrong.

Weight

2.3 kg tube

About 5 lb. It rides on a star tracker or the smallest equatorial mounts, packs easily, and keeps the total cost of a first imaging setup modest.

Mount

OTA only

No mount included, but very little is required. A tracker with a decent polar alignment will produce round stars at this focal length and weight.

02The Polaris Score

How it scores, and why.

84/ 100

Askar 71F Flat-Field Refractor

#4 of 8 imaging APO refractors

Performance

Ease of use

Portability

Upgrade potential

Polaris weighs optical capability, how easy the scope is to live with, how portable it is, and how far it takes you before you outgrow it — not list price or brand.

03Who it's for