THE SKY-WATCHER AZ-GTI ALT-AZ AND SKYMAX 102 Sky

EQUIPMENTTHE SKY-WATCHER AZ-GTI ALT-AZ AND SKYMAX 102Sky-Watcher’snew dreamteamAZ-GTiDesign:WiFi GoTo alt-azimuth Mount (3/8-inchscrew thread)Controlled by free SynScan app(Android and iOS) or SynScan handcontroller (available separately)Can be interfaced with third-partyplanetarium softwareSynScan app alignment method:brightest star alignment, north-levelalignmentFeatures Freedom-Find Dual-EncodertechnologyPointing accuracy:up to 10 arcminutes (RMS)Tracking rates:sidereal, lunar, solar, alignment-freesolar trackingPower supply:8AA batteries or external powersupply (DC 7.5–14V, 0.75A)SkyMaxSteve Ringwood tests the dual packageof the Sky-Watcher AZ-GTi alt-az mountand the new SkyMax 102 Maksutovtelescope and finds that smooth motionsand crisp views are their stock in trade.A general view of the Sky-Max 102 on the AZ-GTi,showing the eyepiece configuration and red dot finder.102astronomynow.com January 2018Design:MaksutovAperture:102mmFocal ratio:f/12.7Focal length:1,300mmSupplied eyepieces:25mm and 10mm (52 and 130 )Finder:unity – red dotPackage price: 419 SRP

REVIEWED: THE SKY-WATCHER AZ-GTIUnless you are into long-durationastrophotography, the development ofalt-az GoTo systems has almost obliteratedthe need for the sometimes entanglingequatorial mount. Simple, intuitive pointingand easier instrument balancing means thatsuch mountings are ideal for many observers –particularly those using telescopes for the first time.In this package, the advantages of an alt-azconfiguration have been mated with a 102mm(four-inch) Maksutov telescope – an ideal compactoptical system that is easy to deploy – with anaperture that will yield most of what the sky has tooffer at a focal length that can deliver fine detail.It seems a dream team – and I was eager to seewhether it was a marriage made in heaven.The AZ-GTi GoTo mountOut of the box, it looks almost too small to bea GoTo mechanism. Yet I found that the neatlystyled L-shaped mounting was easily capable ofthrowing its two-kilogram SkyMax around thesky with not a quiver of strain, even when I usedlarge eyepieces. Indeed, sporting a 45mm SkyWatcher/Vixen type dovetail saddle, it is capableof hefting five kilograms.I was sent no hand controller, for the best trickthis mount has to offer is that it can be controlledcable-free through its own WiFi connection witha smart device (iOS or Android), using the freeSky-Watcher SynScan application. It took onlymoments to download and install this app onmy Samsung Galaxy S5. (It is also capable ofinterfacing with third-party planetarium software.)Initialising SynScan, there is a brief partneringprocedure to connect the mount to your device.The software’s main screen then offers a plethoraof functionality – not being a conventional handpaddle with limited text display, the screen is fullof detail and options – and at night the screenswitches to red-light mode. Of course, beforeI began the planned mechanical and opticalchallenges, stellar alignment was required toenable GoTo functionality.Touching the ‘alignment’ icon presented mewith options of ‘brightest star’ or ‘north level’,of which I chose the former. The softwareimmediately provides a list of available stars.Some of these I thought were a little obscure –particularly to a novice who might need to runfor a star atlas. Making it easy for myself, I choseVega. Using the screen’s directional ‘pads’ and thetelescope’s red dot finder, I was able to accuratelyslew the SkyMax to my prey in just a few seconds.Pressing the panel’s tick mark to indicate myalignment’s arrival, nothing happened. Mentallyshrugging, I veered off a little, returned Vega tothe eyepiece field’s centre and pressed the tickThe tube livery is black, withembedded frosty sparkles,and looks quite smart.again (perhaps this time a little harder!). Again,the software refused to acknowledge my actionand did not move on to further functionality.Burrowing into the help pages, I found that thetick confirmation is only enabled if the ‘up’ and‘right’ direction buttons are previously pressedin sequence. Thus, you can only completealignment when, once aligned, you mis-alignit by short presses of these buttons – or youjudge carefully a deliberate mis-alignmentlow and to the left, so that in enablingthe tick confirmation you arrive alignedas a result. This is totally bizarre. If Icentre a star, I should be able to simplypress enter (tick-wise) – end ofstory. Pressing other buttons as aninitiation sequence that results inThe AZ-GTi head atopmovement from the position youthe tripod and optionalare confirming makes no sense254mm (10-inch)column extension.to a user – nor, I would haveAll images: Martinthought, to a software orRingwood.hardware engineer.Once the first staralignment has beenconfirmed, the mountautomatically slews tothe second star – whereyou repeat the minorcorrections and confirm.Apart from the oddityabove, the SynScan GoTosystem performs superbly;screens are easy to followand wonderful to use. Thereare no battles of confusion;data is presented in a veryuser-friendly fashion andeach screen almost strainsto be helpful. When youalight on a target (there isa rather exciting proximitycountdown as you do so), thescreen is full of co-ordinates andother information. While observinga planet, you can even see itsstellar co-ordinates slowly changedynamically. That’s cool.The control panel features a hand controller port, DCexternal power socket, SNAP port, power switch andpower/WiFi LED indicator. The SNAP port, via an umbilicalto a DSLR, allows control of camera operation.103

EQUIPMENTHard to lose alignmentBelow: A close up of the reddot finder.Bottom: The tinny eyepiecesare so light that initially Ithought their cardboard boxeswere empty!I used the stellar and deep-sky lists offered bySynScan to leap about the sky – but my effortsdid not dizzy it for one minute. There were afew times when my target was not central, butit was always in the field of a moderate powereyepiece. That is impressive. What’s more, it evenalighted accurately on the Moon – a target thatperversely is a problem for many GoTo systems.The second feather in this particular cap is thatthe mount features Freedom-Find Dual-Encodertechnology. This enables you to manhandle thetelescope tube to any new position, withoutlosing the captured alignment or GoTo facility.So even if your target is not in the object lists(or even if it is) you have the option of directingthe telescope towards it without recourse to theSynScan control screen – and thence continue touse the GoTo functions regardless.The mount featuresFreedom-Find Dual-Encodertechnology that enablesyou to manhandle thetelescope tube to any newposition without losing thecaptured alignmentOne unexpected discovery concerned theuse of a smart device itself. In a conventionalhandset a finger is capable of feeling the raised3D buttons and, with familiarity, which buttonis which. On a smooth glassy screen there is nopositional feedback, so imparting instructionsrequires the screen to be looked at, particularlyduring navigation when I found that the screenand eyepiece field have to be viewed almostsimultaneously. Although the SynScan screensare red light-illuminated, having to keep glancingbetween the eyepiece field and device screencan be quite irksome. In the winter, I wonder howstubby-fingered gloved hands will fare. It is worthnoting therefore that along with the untetheredadvantages of WiFi, the mount can be used with aconventional wired SynScan hand paddle.The telescopeMaksutov optical systems are amazing. The foldedlight path enables astonishing focal lengthsto be collapsed into very short and practicaldimensions. In the case of this f/12.7 system, thelight path is compacted into an instrument littlemore than a fifth of its 1.3-metre focal length.The tube livery is black, with embedded frostysparkles. It looks quite smart. However, I didnotice that because of this colour’s good infraredabsorbance, just a few moments in sunlightheats the tube up quite quickly. It is probablywise to separate solar and night-time observingby quite a few hours. While I’m mentioningsunlight, I did test SynScan’s safety credentialsby directing the software to point at the Sun. Amessage appeared saying that my target wasnear the Sun and did I want to continue. Topmarks for an earnest if slightly muddled caution.The supplied star diagonal goes into a 1.25inch focuser featuring the double thumbscrewsthat have been appearing on equipment lately.Someone somewhere must think this is a goodidea; but I have to admit I have not ‘got it’, yet.Having to undo and retighten screws twice whenchanging eyepieces seems oddly overdone to me.I began by using the supplied eyepiece; a‘Super 25 Wide Angle Long Eye Relief’ accordingto its label. Filling it with a convenient field of104astronomynow.com January 2018

REVIEWED: THE SKY-WATCHER AZ-GTIstars (provided by the Pleiades open cluster),their appearance at once prompted me toswap the eyepiece out for one of mine, a fairlyaverage 25mm Meade Plössl. I have hardlyever seen such a stark difference between twoeyepieces of the same focal length. Although notan especially expensive or exotic eyepiece, theMeade supplied a field that was so much cleaner,sharper and darker than the so-called SuperPlössl supplied. A pet irritation of mine, I simplydo not understand the logic behind supplyingan instrument with eyepieces that are unable toshow the best of what the telescope is capableof. The inexperienced, especially, will assume theworst and condemn the whole telescope. Howmany of these, eagerly purchased, have endedup discarded shortly afterwards – along with anascent scientific curiosity, perhaps?In this respect I would much rather eyepieceswere not included; since by this penn’orth of tarthey ruin the whole ship. There was also a ‘Super10’, but as a service to the telescope, I continuedonly with eyepieces of my own.Deep-sky delightsI decided to begin the telescope’s assessmentwith a few deep- sky objects. Hitting SynScan’sdeep-sky icon, the app obligingly supplied mewith familiar objects that were currently abovethe horizon – exactly the list I wanted.With an appetite whetted by the enhancedview I had achieved of the Pleiades, I opted forthe twin stellar splash of the Double Cluster inPerseus as a challenging demonstration of thetelescope’s mettle. At 52 , my 25mm could notquite encompass both cores so I switched to33 with a wider field, but rather heavier, 40mmeyepiece. The telescope took this on board withalacrity – no whine of straining gears or driftingfield. The switch was rewarding. The sky now freeof the seemingly eternal summer twilight, thestar field’s twin clusters veritably glowed againsta velvety black background. Focusing verycarefully, star images held very well to the fieldextremity – the clusters looking like apair of molten shotgun blasts againstthe night.Much closer to the zenith,the Andromeda Galaxy was anirresistible temptation. Despite theangular distance from my previoustarget, the AZ-GTi successfullynavigated the gap and broughtitself to a well-centred stop on thegalaxy. I have to say that watchingthe angular countdowns on thescreen while a slew was takingplace became rather fun.M31’s lenticular glow was ajoy – and bright; the core lookedquite condensed and stellar. Looking forsomething more diffuse and challenging,I requested SynScan to take me to the VeilNebula in Cygnus. I find this object oftenLeft: the SynScan splashscreen with initial icons. I likedthe fact that the directional slewpad included diagonalmovement.Middle: during a slewtowards its target, SynScanprovides a proximity countdownin RA and Dec.Right: SynScan automaticallylists objects currently availableto the observer.The AZ-GTi head can handle loads of up to fivekilograms, attached to the dovetail saddle that allowstrouble-free optical tube deployment.105