What focal length does the Celestron C11 EdgeHD reach with the 0.7x reducer?

Celestron states 2,800 mm at f/10. With the 0.7x reducer my frames plate-solve at 1,952 mm, 0.397 arcsec per pixel on the 3.76 micron pixels of the ASI2600MM, which is close to f/7.

How heavy is the C11 EdgeHD, and what mount does it need?

Celestron states 13 kg for the tube. With my reducer, filter wheel and camera the payload was almost 14 kg, 70% of the ZWO AM7's rating without a counterweight.

Is the C11 EdgeHD hard to guide?

At this focal length, yes. I was really struggling to guide it with the guiding sensor built into my camera in narrowband, so for the AM7 guiding test I moved the same camera to the Askar SQA106.

What field of view does it give?

0.69 x 0.46 degrees with the 0.7x reducer on a 26 MP APS-C sensor. The Dumbbell, Thor's Helmet and M 13 fill it; the Rosette and the Veil show only a part.

Can the C11 EdgeHD image the planets?

Yes. At its native 2,800 mm my captures of Jupiter show the belts and festoons, and Mars shows its dark surface markings.

How does it compare with the Askar SQA106 on the same target?

On the Elephant's Trunk the C11 EdgeHD frames the trunk alone at about 1,950 mm, where the SQA106 takes in a wide field of IC 1396 at 505 mm. Side by side on the same patch of sky, the C11 shows the edges of the trunk in far finer detail.

Does the C11 EdgeHD work with a HyperStar lens?

Celestron says every EdgeHD tube is Fastar compatible: the secondary mirror comes out for a third-party lens at f/2. I have only a short test stack that way, nothing finished.

What have I not tested on the C11 EdgeHD?

I have not used the C11 EdgeHD visually, measured its cool-down time or how well its collimation holds, or finished an image with a HyperStar lens at f/2.

Celestron C11 EdgeHD review: an 11-inch beast for narrowband

Where does it rank on our leaderboard

Nine of the 42 telescopes on my board, against price
Rank	Telescope	Stars for Your Buck	Recorded UK price
1	Askar 50P	95 out of 100	£299
2	ToupTek Hope D60	93 out of 100	£749
8	Askar 60F	87 out of 100	£498
18	Celestron C11 EdgeHD	75 out of 100	£4,845
19	Sky-Watcher Heliostar 76Ha	74 out of 100	£2,399
29	William Optics RedCat 51	69 out of 100	£849
36	Nakoh 60GT	52 out of 100	£899
41	Celestron 114 LCM	42 out of 100	£361
42	Celestron AstroMaster LT 76	13 out of 100	£200

Contents

01 Where does it rank on our leaderboard
02 Specifications and features
03 In the hand
04 How good is it? Here's what I captured
05 Planets and the Moon
06 Raw against finished
07 The rig on the mount
08 What is it for
09 Versus the Askar SQA106
10 Watch the review
11 Tested numbers and the download
12 Should you buy it?
13 Questions and more about this review

In 30 seconds

Stars for Your Buck 75/100

Reviewed 12 Feb 2026 Updated 23 Sep 2026

Rank: #18 of 42 telescopes
Verdict: Damon recommends

Written by Damon Scotting 6 min read

Buy it if

You want small targets large: planetary nebulae, galaxy cores and nebula detail at about 1,950 mm with the 0.7x reducer
You have a mount that carries 14 kg of telescope and camera without strain, ideally on a pier
You will put in long narrowband integrations: the frames here took 3 to 12 hours

Skip it if

You want wide nebulae: even with the reducer the field is 0.69 x 0.46 degrees on an APS-C sensor
You want easy guiding: at this focal length an on-camera guide sensor struggles, above all in narrowband
You need something to carry out each night: the tube alone weighs 13 kg

The Celestron 11 inch EdgeHD is a beast, a very powerful telescope with an incredibly long focal length, but I was really struggling to guide with it.

Specifications and features

Against the telescopes I have reviewed

Compare with

Celestron C11 EdgeHD reviewed #18 of 42	Celestron 8" EdgeHD #5 of 42
Recorded UK price	£4,845	£1,999
Stars for Your Buck	75/100	90/100
Aperture	279.4 mm (11 in)	203.2 mm (8 in)
Focal length	2,800 mm	2,032 mm
Focal ratio	f/10	f/10
Optical design	EdgeHD aplanatic Schmidt-Cassegrain	EdgeHD aplanatic Schmidt-Cassegrain
Image circle	42 mm with the 0.7x reducer	APS-C sensors with the 0.7x reducer
Back focus	146 mm with the 0.7x reducer	105 mm with the 0.7x reducer
Focuser	Moving primary mirror with mirror clutches	Moving primary mirror with mirror clutches
Weight, tube	13 kg (28 lb) optical tube	6.35 kg (14 lb) optical tube
Length, tube	610 mm (24 in)	432 mm (17 in)
Dew shield	not included	not included
In the box	9x50 finderscope, 2 in mirror diagonal with 1.25 in adapter, 23 mm Luminos 2 in eyepiece, CGE dovetail bar	40 mm Plossl 1.25 in eyepiece, 9x50 finderscope, 1.25 in star diagonal, CGE dovetail bar

In the hand

Six A7S frames

How good is it? Here's what I captured

Ten targets

M 27, ASI2600MM, Scorpio 3 nm HSO

Integration: 12 h
Field: 0.64 x 0.43 degrees
Telescope: Celestron C11 EdgeHD with the 0.7x reducer
Camera: ZWO ASI2600MM
Mount: ZWO AM7
Target: M 27 Dumbbell Nebula
Type: Planetary nebula
Location: Bortle 6.8 (in my garden)

IC 1396, ASI2600MM, HSO

Integration: 8 h
Field: 0.67 x 0.45 degrees
Telescope: Celestron C11 EdgeHD with the 0.7x reducer
Camera: ZWO ASI2600MM
Mount: ZWO AM7
Target: IC 1396 Elephant's Trunk Nebula
Type: Emission nebula with a dark globule
Location: Bortle 6.8 (in my garden)

NGC 2359, ASI2600MM, HSO

Integration: 3 h
Field: 0.64 x 0.43 degrees
Telescope: Celestron C11 EdgeHD with the 0.7x reducer
Camera: ZWO ASI2600MM
Mount: ZWO AM7
Target: NGC 2359 Thor's Helmet
Type: Emission nebula around a Wolf-Rayet star
Location: Bortle 6.8 (in my garden)

IC 434, ASI2600MM Pro, HSO

Integration: 2 h 15 min
Field: 0.66 x 0.45 degrees
Telescope: Celestron C11 EdgeHD with the 0.7x reducer
Camera: ZWO ASI2600MM Pro
Mount: ZWO AM7
Target: IC 434 Horsehead Nebula
Type: Dark nebula
Location: Bortle 6.8 (in my garden)

M 1, ASI2600MM Pro, LRGB

Integration: 3 h
Field: 0.44 x 0.28 degrees
Telescope: Celestron C11 EdgeHD with the 0.7x reducer
Camera: ZWO ASI2600MM Pro
Mount: ZWO AM7
Target: M 1 Crab Nebula
Type: Supernova remnant
Location: Bortle 6.8 (in my garden)

NGC 2237, ASI2600MM, HSO

Integration: 1 h
Field: 0.69 x 0.46 degrees
Telescope: Celestron C11 EdgeHD with the 0.7x reducer
Camera: ZWO ASI2600MM
Mount: ZWO AM7
Target: NGC 2237 Rosette Nebula (core)
Type: Emission nebula
Location: Bortle 6.8 (in my garden)

M 13, ASI2600MC

Integration: 1 h
Field: 0.69 x 0.46 degrees
Telescope: Celestron C11 EdgeHD with the 0.7x reducer
Camera: ZWO ASI2600MC
Mount: ZWO AM7
Target: M 13 Hercules Globular Cluster
Type: Globular cluster
Location: Bortle 6.8 (in my garden)

NGC 6960, ASI2600MC

Integration: 1 h
Field: 0.69 x 0.46 degrees
Telescope: Celestron C11 EdgeHD with the 0.7x reducer
Camera: ZWO ASI2600MC
Mount: ZWO AM7
Target: NGC 6960 Western Veil Nebula
Type: Supernova remnant
Location: Bortle 6.8 (in my garden)

M 31 core, LRGB

Integration: 1 h
Field: 0.63 x 0.35 degrees
Telescope: Celestron C11 EdgeHD with the 0.7x reducer
Camera: Unknown
Mount: ZWO AM7
Target: M 31 Andromeda Galaxy (core)
Type: Spiral galaxy
Location: Bortle 6.8 (in my garden)

M 51

Integration: Unknown
Field: 0.23 x 0.13 degrees
Telescope: Celestron C11 EdgeHD with the 0.7x reducer
Camera: Unknown
Mount: ZWO AM7
Target: M 51 Whirlpool Galaxy
Type: Spiral galaxy
Location: Bortle 6.8 (in my garden)

Planets and the Moon

Jupiter and Mars

Jupiter

Date: 24 Feb 2025
Gear: Celestron C11 EdgeHD at 2,800 mm; camera not recorded

Mars

Date: 24 Feb 2025
Gear: Celestron C11 EdgeHD at 2,800 mm; camera not recorded

Raw against finished

The rig on the mount

The 4 targets, the raw combined stack against my finished image, each with its integration, the camera and the palette:

M 27 Dumbbell Nebula: 12 h of light, ASI2600MM, Scorpio 3 nm HSO, the raw combined stack with one automatic stretch
IC 1396 Elephant's Trunk Nebula: 8 h of light, ASI2600MM, HSO narrowband, the raw combined stack with one automatic stretch
NGC 2359 Thor's Helmet: 3 h of light, ASI2600MM, HSO narrowband, the raw combined stack with one automatic stretch
IC 434 Horsehead Nebula: 2 h 15 min (45 x 180 s) of light, ASI2600MM Pro, HSO narrowband, the raw combined stack with one automatic stretch

On the ZWO AM7, then on six other mounts

What is it for

In my words

A very long focal length for narrowband

It is a beast. Connected to the telescope I have a 0.7 times reducer, a T-adapter, a camera angle adjuster from ZWO, a 7 by 2 inch filter wheel and the ASI2600MM Air camera. With this setup I take really nice quality narrowband images of the night sky at a very long focal length.

Almost 14 kg on the mount

The AM7 mount makes the telescope itself look deceptively lightweight. It's not. The payload is almost 14 kg in total, which is 70% of the maximum recommended payload for that mount without a counterweight.

Versus the Askar SQA106

Elephant's Trunk on both, plate-solved and star-aligned (residual 2.99 px per 1000)

The same target on the Askar SQA106
Target	Telescope	Integration	Subs	Filter	Nights
IC 1396 Elephant's Trunk Nebula	Celestron C11 EdgeHD	480 min	not recorded	HSO narrowband	November 2025
IC 1396 Elephant's Trunk Nebula	Askar SQA106	90 min	30 x 180 s	Laida 5 nm HSO	24 Apr 2026

Watch the review

One of the BEST Mounts in the WORLD or Underwhelming...? (AM7 Review) · published 4 May 2026 · 8:21 · Watch on YouTube · 12,503 views, 423 likes on 2 Oct 2026

Jump to

0:00 Out with the old, in with the new
0:14 Almost 14 kg of C11 EdgeHD with no counterweight
1:00 First impressions, building the rig
1:30 The full back-end, C11 Edge HD + reducer + filter wheel + 2600MM Air
1:57 My images through the C11 EdgeHD
2:00 Why I had to switch to the Askar SQA-106
2:20 Guiding the C11 EdgeHD with the camera's built-in sensor

Check out more videos on the Celestron C11 EdgeHD

The Night Sky through my 11-INCH Telescope!

12 Feb 2026

Tested numbers and the download

Finished image

Licence: for personal use, credit Damon Scotting. Both JPEGs 4,096 x 2,733 px.

-10 C sensor temperature during imaging set point -10 C

1952 mm focal length, plate solved Celestron states 1960 mm

0.69 x 0.46° field of view 6,248 x 4,176 px on ASI2600MM Pro

26 MP ASI2600MM Pro 6,248 x 4,176 px, 23.5 x 15.7 mm

Should you buy it?

75/100 Stars for Your Buck

Pros

With the 0.7x reducer it takes really nice quality narrowband images at a very long focal length: my frames plate-solve at 1,952 mm.
As far as making out the structure of Thor's Helmet goes, I am very happy with it.
It has the reach for the planets: my Jupiter shows its belts and festoons, and Mars its dark surface markings.
One hour of LRGB resolves the dust lanes wrapped around the core of the Andromeda Galaxy.
Celestron makes the reducer for it: f/7, 146 mm of back focus and a 42 mm image circle, bigger than any APS-C sensor.

Cons

Guiding is hard at this focal length: imaging in narrowband with an on-camera guiding sensor, the guide camera really suffers.
It is heavy: 13 kg for the tube and almost 14 kg with the imaging train, so it needs a serious mount.
The field is small: 0.69 x 0.46 degrees with the reducer on an APS-C sensor, too tight for the whole Rosette or Veil.
At its native f/10 it is slow for deep sky, and the 0.7x reducer is a separate purchase, $849 at Celestron.

It is a beast.

Who the C11 EdgeHD is for

Deep-sky imager with a pier

Buy

279 mm at about 1,950 mm with the reducer: 12 hours on the Dumbbell and 8 hours on the Elephant's Trunk show what it does with time.

Planetary imager

Buy

At 2,800 mm native, Jupiter's belts and festoons and the dark markings on Mars show in my captures.

Owner of a small strain-wave mount

Skip

The tube is 13 kg before a camera goes on. My recommendation is the Celestron 8 inch EdgeHD, 6.35 kg of the same design.

Wide-field nebula imager

Skip

0.69 x 0.46 degrees crops the Rosette to its core. My recommendation is the Askar SQA106.

Complete beginner

Skip

A 13 kg tube with no mount, and hard to guide. My recommendation is the Celestron NexStar 6SE, a 150 mm Schmidt-Cassegrain on its own GoTo mount.

Owner of an 8 inch EdgeHD

Skip

Over a third more aperture costs twice the tube weight, 13 kg against 6.35 kg, and a much bigger mount.

Three alternatives I have reviewed

Questions and more about this review

Reviewed by

Damon Scotting

The Telescope Man Verified

BSc (Hons) Physics with Astrophysics and Cosmology, Loughborough University PGCE / QTS, University of Nottingham

About Damon About Damon Damon Scotting is The Telescope Man. He holds a BSc (Hons) in Physics with Astrophysics and Cosmology from Loughborough University and a PGCE with QTS from the University of Nottingham, and taught physics in secondary schools before becoming an astronomy creator. He is a contributing writer for BBC Sky at Night Magazine and the author of 42 Wonders of Our Night Sky, and his photograph of the galaxy M100 with the dwarf planet Ceres was Highly Commended in the Astronomy Photographer of the Year 2024 competition run by Royal Observatory Greenwich. He has appeared on the BBC's Blue Peter. More than 750,000 people follow his astronomy channels on YouTube, Instagram and TikTok, and he has reviewed more than 140 telescopes, mounts, cameras, filters and accessories hands-on for this site. More about Damon · How I test · Damon's book

I review all kinds of gear: most of it I buy, some is gifted and some is loaned, and all of it is reviewed the same way. How this site is funded

Eight questions, answered

Questions about the Celestron C11 EdgeHD

Reviewed 12 February 2026 ·Updated 23 September 2026

I review all kinds of gear. Most of it I buy, some is gifted and some is loaned, and all of it is reviewed the same way: no company sees or approves a review before it is published. Shop links marked Ad are affiliate links: I earn a commission when you buy through them, at no extra cost to you. How this site is funded

What focal length does the Celestron C11 EdgeHD reach with the 0.7x reducer? Celestron states 2,800 mm at f/10. With the 0.7x reducer my frames plate-solve at 1,952 mm, 0.397 arcsec per pixel on the 3.76 micron pixels of the ASI2600MM, which is close to f/7. Tested numbers and the download ↓
How heavy is the C11 EdgeHD, and what mount does it need? Celestron states 13 kg for the tube. With my reducer, filter wheel and camera the payload was almost 14 kg, 70% of the ZWO AM7's rating without a counterweight. The rig on the mount ↓
Is the C11 EdgeHD hard to guide? At this focal length, yes. I was really struggling to guide it with the guiding sensor built into my camera in narrowband, so for the AM7 guiding test I moved the same camera to the Askar SQA106. Watch the review ↓
What field of view does it give? 0.69 x 0.46 degrees with the 0.7x reducer on a 26 MP APS-C sensor. The Dumbbell, Thor's Helmet and M 13 fill it; the Rosette and the Veil show only a part. What I captured ↓
Can the C11 EdgeHD image the planets? Yes. At its native 2,800 mm my captures of Jupiter show the belts and festoons, and Mars shows its dark surface markings. Planets and the Moon ↓
How does it compare with the Askar SQA106 on the same target? On the Elephant's Trunk the C11 EdgeHD frames the trunk alone at about 1,950 mm, where the SQA106 takes in a wide field of IC 1396 at 505 mm. Side by side on the same patch of sky, the C11 shows the edges of the trunk in far finer detail. Versus the Askar SQA106 ↓
Does the C11 EdgeHD work with a HyperStar lens? Celestron says every EdgeHD tube is Fastar compatible: the secondary mirror comes out for a third-party lens at f/2. I have only a short test stack that way, nothing finished. The specifications and the comparison table ↓
What have I not tested on the C11 EdgeHD? I have not used the C11 EdgeHD visually, measured its cool-down time or how well its collimation holds, or finished an image with a HyperStar lens at f/2.