Sky-Watcher Flextube 200P SynScan

At a Glance

• Aperture: 203 mm
• Focal length: 1200 mm
• Focal ratio: f/5.9
• Focuser: 2-inch single-speed Crayford-style with 1.25-inch adapter
• Finder: 9x50 straight-through
• Control: SynScan GoTo hand controller, built-in Wi-Fi

Product Overview

The Sky-Watcher Flextube 200P SynScan is a 203 mm computerised Dobsonian: a 1200 mm f/5.9 parabolic Newtonian on a collapsing truss tube, driven by dual-axis servo motors and a SynScan hand controller with a 42,900-object database. It finds targets for you, tracks them once found, and packs down for transport, which is an unusual combination at this price.

The optical tube collapses along its truss rods and locks, transporting as two pieces — tube and rocker box — that reassemble in seconds and hold collimation through the cycle. The primary is borosilicate, parabolic, and coated with Sky-Watcher's Radiant Aluminum Quartz finish at 94% reflectivity, gathering 814 times the light of the unaided eye.

Who It's For

This is a good match if you want eight-inch-class aperture without spending your observing time hunting for objects. The GoTo system turns a session into looking at things rather than looking for them, which matters most when your sky is light-polluted enough that star-hopping is genuinely hard.

It also suits you if you observe with others — outreach nights, family, visitors — where being able to put a named object in the eyepiece on request is worth more than the satisfaction of finding it yourself. And it works for observers who travel, since the collapsing tube and two-piece transport were designed around exactly that trip.

Key Features & Design

• SynScan GoTo with 42,900-object database: the complete Messier, NGC and IC catalogues plus partial SAO and 25 user-defined slots, so the limit on what you observe is your sky rather than your ability to locate it.
• Freedom Find dual encoders: you can grab the tube and move it by hand at any point without losing alignment, so the GoTo system and manual sweeping coexist instead of being an either/or choice.
• Dual-axis tracking at sidereal, lunar and solar rates: objects stay centred once found, which is what makes high magnification practical and lets a queue of people each get a proper look.
• Built-in Wi-Fi: the mount can be driven from a phone or tablet as well as the hand controller, so the sky atlas you already use can do the pointing.
• GoTo accuracy to 5 arc minutes: targets land inside the field of a medium-power eyepiece, so a slew ends with the object visible rather than with a hunt around the neighbourhood.
• Collapsible truss tube: the scope shortens for transport and storage and returns to collimation on extension, so the aperture is one that travels.
• Patented tension control handle: altitude friction is adjustable, keeping the tube balanced as you swap between light and heavy eyepieces.

Optical / Mechanical Design

At 203 mm and 1200 mm focal length the scope works out to f/5.9, which is a comfortable ratio to build eyepiece collections around. It is slow enough that ordinary eyepieces behave well toward the field edge — noticeably more forgiving than the f/4.7 instruments further up this range — and fast enough to keep the tube short and the magnifications sensible with common focal lengths.

The drive is DC servo motors reading a motor encoder at 1,620,000 counts per revolution and a main-axis encoder at 11,748 counts per revolution. The main-axis encoder is what Freedom Find depends on: because position is measured at the axis itself rather than inferred from motor turns, the system still knows where the telescope points after you have moved it by hand. Slew speeds run from 1.0x to 1000x, so the same control both crosses the sky and makes fine centring adjustments.

The focuser is a 2-inch single-speed Crayford-style unit with a 1.25-inch adapter. Single-speed means one focus knob ratio rather than a fine-focus reduction gear — at f/5.9 the depth of focus is forgiving enough that this is workable, though a fine-focus upgrade is a common later addition for planetary observers.

Recommended Uses

Guided visual deep-sky observing is the core use: working through Messier and NGC lists efficiently, comparing objects back to back, and observing from suburban skies where finding faint targets manually is the hardest part of the night.

Lunar and planetary observing benefits from the tracking, since the object stays put while you study it rather than drifting out mid-observation. Public outreach is another strong fit — request an object, slew, and let people look while the mount holds it centred. Short-exposure lunar and planetary imaging with a small camera is workable within the limits described below.

Compatibility and Accessory Notes

The 2-inch focuser accepts 2-inch eyepieces directly and 1.25-inch eyepieces through the supplied adapter. Sky-Watcher includes a 9x50 straight-through finderscope and two 4-element 1.25-inch Plössl eyepieces, 12.5 mm and 20 mm, giving roughly 96x and 60x at this focal length.

The mount runs on 10 to 15 V DC at 1 A through a 2.1 mm centre-positive plug. A regulated supply or a field battery pack in that range is what the system expects, and it is worth sorting out power before the first clear night rather than during it.

UHC and O-III nebula filters thread into standard eyepiece barrels and suit this aperture well on emission targets. A collimation tool is a sensible companion purchase, as with any Newtonian. If you want help matching eyepieces, filters or a power solution to this scope, send us your setup and we will work it out with you.

Good to Know Before You Order

Sky-Watcher's bullet list mentions back focus for astrophotography — read that carefully. The collapsing tube does provide enough back focus to reach focus with a camera, and that part is true. What it does not change is the mount: a Dobsonian rocker box is alt-azimuth, so even with tracking holding an object dead centre, the field of view slowly rotates around it. Long exposures smear as a result, and no amount of tracking accuracy fixes it. Short-exposure lunar and planetary video is the realistic imaging ceiling unless you add an equatorial platform underneath the base.

The focuser is single-speed. There is no 10:1 fine-focus reduction on this model. At f/5.9 that is manageable, and many owners live with it indefinitely, but planetary observers chasing critical focus often upgrade later. It is worth knowing before you order rather than discovering at the eyepiece.

Alignment happens at the start of each session. The GoTo system needs a Brightest-Star or Two-Star alignment before it can point accurately. It takes a few minutes and the hand controller walks you through it, and Freedom Find means that once done, moving the scope by hand will not undo it.

It ships as an optical tube and a separate base. Both are manageable by one person, but it is a two-trip carry from the vehicle rather than a single lift.

Frequently Asked Questions

Is it difficult to set up?

No. The tube extends and locks on its truss rods, drops into the rocker box, and the hand controller runs you through a two-star alignment with prompts. The first night takes longer while you learn the menu system, and after that setup is a few minutes. No tools and no software are needed to get observing.

What does Freedom Find actually do for me?

It means the telescope is never in the wrong mode. With most GoTo mounts, shoving the tube by hand destroys the alignment and you start over. Here a separate encoder on each axis reports the true position, so you can push the scope across the sky to look at something, then hand control back to the computer and it still knows where it is.

Can I do astrophotography with it?

Lunar and planetary imaging with a short-exposure camera, yes. Deep-sky imaging, no — the alt-azimuth mount rotates the field during an exposure regardless of how well it tracks. An equatorial platform under the base is the usual workaround if you want to push further. If deep-sky imaging is the real goal, an equatorial mount and a different tube is the more direct route, and we are happy to talk that through.

How is this different from the manual Flextube 200P?

Same collapsing-tube concept and the same aperture class; this one adds the computerised drive, the object database, tracking and Wi-Fi control. You are paying for not having to find and follow things yourself. If star-hopping is part of what you enjoy about observing, the manual version costs considerably less and gives the same view.

Will my 2-inch eyepieces work?

Yes, directly in the focuser, and the supplied 1.25-inch adapter covers the smaller format. Both sizes work without buying anything.

What do I need to power it?

A regulated 10 to 15 V DC supply capable of 1 A, with a 2.1 mm centre-positive plug. A mains adapter works at home and a portable power pack covers field use. Ask us if you want a recommendation that suits how you observe.

Bottom Line

In short: a 203 mm f/5.9 collapsible Dobsonian with SynScan GoTo, dual-axis tracking, Wi-Fi control and Freedom Find encoders that let you move it by hand without losing alignment. It is built for visual observing, it packs down for the drive to darker sky, and it puts objects in the eyepiece for you.