Top positive review
57 people found this helpful
Good compact scope - value for money - good for planets
on 3 June 2015
I bought the 127mm Sky-Watcher 127mm objective lens GoTo scope as a first step-up from a not-that-bad £20 car-boot-sale 'manually-pointed' telescope.
The problem with a telescope that does not have a computerised mount is actually finding anything to look at. Even something as large as the moon, which is 0.5 degrees wide when full, can be a bit tricky to find in your telescope, while Jupiter, which is 140,000km in diameter (albeit 800 million kilometers away) appears to be only about 40 arc seconds (1 degree = 3600 arc seconds), or about one hundredth of a degree: even though you can see it perfectly with your eye or with binoculars, it can be very difficult to find it with a telescope! So finally I took the plunge and bought this computerised goto 'scope. Now, in theory, I can easily find and look at all sorts of things, but there is theory and then there is practice.
The telescope when it arrived was as described and most impressive. The tripod is fairly sturdy, the mount itself is compact, relatively light and rigid, while the optical tube assembly (OTA) - 'The Telescope' - is high quality: you can see where your money has gone. The little finder-scope has high quality optics, with cross wires thick enough to obscure a star (which can be useful in the dark, since you can centre the scope perfectly by covering the star completely with the wires). The finder scope needs to be well-set-up: best to align it in the daylight on a distant object, and then let the telescope cool down in-situ ready for observing. Ideally you will have a stable base to put the tripod on (concrete or paving slabs, for instance) and you have to be careful not to kick the tripod's legs as you move around, as we will see...
Once you have prepared the telescope for observing (and yourself: in winter two pairs of socks, warm hat, gloves, several layers, if required), it will be time to orient the scope. Firstly, the scope has to be perfectly level: use the bubble-level on the tripod (again, probably best done in the light). Go through the set-up instructions, and remember to put in the correct date and the absolute right time (have a digital watch or similar handy for this - you can do this earlier, in the light, to make it a bit easier). I bought the PowerTank battery, so keeping the scope powered for a couple of hours until it gets dark is not an issue. To orient the scope, you will be required to point it at one or two different stars. This is the tricky bit, for two reasons: you have to find that tiny point of light in all the great heavens, and you also have to know which stars are which, so that you know which star you are pointing at. If you have correctly set up the finder-scope on the side of your main scope, it should not be too difficult to slew the telescope to point at the star (I find that sighting along the top of the main scope can be a good pre-orientation even for the finder-scope). However, you may find that you have to make some limbo-esque contortions to be able to see through the finder scope if you are trying to spot a star high in the sky. A chair or stool might be a useful accessory.
The second problem is knowing which star you need to point your telescope at, but for me, this has been the best bit of owning the telescope so far. The software in the controller has a list of about 50 stars for you to point your scope at, which will then allow it to work out where it is (and also, perhaps, to correct for any slight deviation for perfect horizontal of the mount). Perhaps you only need to know two specific stars to be able to get away with this orientation each time, but I took it a slightly different way and decided to be able to identify all 50 of them: I wrote them all down, and learned where they were in the constellations, without using binoculars and just with the naked eye. This has been the single most enjoyable thing I have ever done in astronomy! (And it cost me exactly nothing at all and for a miser like me, that is a bonus). If I can do it, then anyone can. A simple star map printed off from the Internet will help immeasurably. To help, here is the list of stars that you will be offered by the software (at 51 degrees north latitude, anyway - it will be a bit different elsewhere, completely different in the southern hemisphere). Incidentally, there is a star called Mizar (in the middle of the handle of the 'Big Dipper' or Plough), which has a companion star called Suha ('forgotten' in Arabic) just visible with the naked eye, which is a test of eye-sight, or, if you know that you can see it, of the seeing conditions.
Here is the list of stars (and the constellation that they appear in) in the order that they are presented by the telescope: Sirius (Canis Major); Zosma (Leo); Sheratan (Aries); Arneb (Lepus); Algieba (Leo); Tsih (Cassiopeia); Menkar/Menkab (Cetus); Phad/Phecda (Ursa Major); Merak (Ursa Major); Alderamin (Cepheus); Mizar (Ursa Major); Caph (Cassiopeia); Almach/Alamak (Andromeda); Schedar (Cassiopeia); Mintaka (Orion); Eltanin (Draco); Saiph (Orion); Mirach (Ursa Major); Kochab (Ursa Minor); Denebola (Leo); Alpheratz/Sirrah (Andromeda); Alnitak (Orion); Algol (Perseus); Polaris (Ursa Minor); Mirzam (Canis Major); Hamal (Aries); Castor (Gemini); Alphard (Hydra); Alkaid (Ursa Major); Alhena (Gemini); Wezen (Canis Major); Mirfak (Perseus); Dubhe (Ursa Major); Alioth (Ursa Major); El Nath (Taurus); Alnilam (Orion); Bellatrix (Orion); Regulus (Leo); Pollux (Gemini); Aldabaran (Taurus); Betelgeuse (Orion); Procyon (Canis Minor); Rigel (Orion); Capella (Auriga).
Once you have chosen your first star, the telescope will slew to your chosen second star, and you just need to use the controller to manually place it in the middle of the main viewfinder to complete the orientation of the scope. The scope will be able to smoothly track any celestial object and is very good at this, with no juddering noticeable. The scope now knows where it is, the time and date and its orientation and can now point in the direction of the 80,000 objects in its software catalogue. Problem is, you won't see most of these objects for two main reasons; light pollution and the limitations of the telescope: Essentially they will be too faint to be perceived by the naked eye using this telescope and its relatively modest light-gathering capabilities. You will be best off looking for brighter objects, including planets and more obvious deep sky objects (DSOs). The scope has the capability of pointing to all of the planets, and Jupiter is a fantastic sight, with the bands clearly seen and even a hint of a disc of the largest moon, but with the Great Spot still eluding me. The phases of Venus can clearly be seen, but perhaps not much more. The rings of Saturn are clear, you can see black space between them and the planet, but you need reasonable seeing conditions, a bit of patience and not to knock the telescope at all (Saturn is a long way away after all, 1.2bn kilometers at its closest to Earth).
The scope comes with a list of DSOs - a kind of 'must-see' tick-list - including nebulae and galaxies. The famous Orion Nebula will fill the viewfinder with its dusty clouds, but this is strictly a monochrome view (long-exposure photos or post-processing will bring out any colour in the view) and this scope will not resolve many details in the clouds. In most cases, it is best to dial down your expectations of what you will see with this scope (but remember, just finding these objects in the first place is quite an accomplishment). It appears that the DSO database offers different objects from summer to winter, and the list below includes all the winter objects plus those also included just in summer (marked '*')
Here is the list of objects in the telescope's galactic tour, in the order in which they are presented by the telescope, as well as some more information on each, its apparent magnitude and right ascension (RA): the order of the DSOs in the list is in general order of magnitude, leading to a lot of slewing between objects if you just proceed down the list. You might want to draw up a list of objects with increasing or decreasing RA to progressively tour the heavens in one direction.
Beehive Cluster, M44,+3.7, 8h40m
Andromeda Galaxy, M31, +3.4, 0h42m
Orion Nebula, M42, +4.0, 5h35m
Christmas Tree nebula, +3.9, 6h41m
Pinwheel Galaxy, M101, +7.86, 14h03m
M41 open cluster, +4.5, 6h46m
Double Cluster, Caldwell 14, +3.7, 2h20m
*M47 open cluster, +4.2, 7h36m
M39, open cluster, +5.5, 21h31m
M34, open cluster, +5.5, 2h42m
Almach, double/quadruple star, +5.5, 2h03m
M35 open cluster, +5.3, 6h09m
Algieba, binary star, -0.3/+1, 10h19m
*Albireo 'double star,' +3.2, 19h30m
Pleiades open cluster, +1.6, 3h47m
M37 open cluster, +6.2, 5h52m
M46 open cluster, +6.1, 7h41m
M67 open cluster, +6.1, 8hr51m
*M5 globular cluster, +6.65, 15h18m
M93 open cluster, +6.0, 7h44m
Hercules Cluster galactic cluster, 16h05m
M38 open cluster, +7.4, 5h28m
Bode's Nebula, M81, spiral galaxy, +6.9, 9h55m
M3 globular cluster, +6.2, 13h42m
M36 open cluster, +6.3, 17h17m
M92 globular cluster, +6.3, 17h17m
M53 globular cluster, +8.3, 13h12m
*M83 spiral galaxy, +7.5, 13h37m
*Dumbell Nebula, M27, +7.5,19h59m
Ghost of Jupiter planetary nebula, +8.6, 10h24m
M18 'Cigar Galaxy,' +8.4, 9h55m
Whirlpool Galaxy, M51, +8.4, 13h29m
Sunflower Galaxy, M63, +9.3, 13h15m
Sombrero Galaxy, M104, +9.0, 12h39m
M32 elliptical Galaxy, +8.1, 00h42m
Black-eye Galaxy, M64, +9.3, 12h56m
Crab Nebula, M1, +8.4, 5h34m
M87 supergiant elliptical galaxy, +9.6, 12h30m
M66 spiral galaxy, +8.9, 11h20m
M65 spiral galaxy, +10.25, 11h18m
Spindle Galaxy, M102, +10.7, 15h06m
Cat's Eye Nebula, +9.8, 17h58m
NGC 891 spiral galaxy, +10.8, 2h22m
*Ring Nebula planetary nebula, +8.8, 18h53m
Blue Snowball nebula, +8.6, 23h25m
Blinking PN planetary nebula, +8.8, 19h44m
Eskimo Nebula, +10.1, 7h29m
Apparently the Hercules Globular Cluster of stars, M13, +5.6, 16h41m is also worth a look. Bode's Nebula and M92 are also highly rated. Under dark skies, you might just be able to see objects with a magnitude of +12 with the scope, so in theory all of the above DSOs are within range of this scope.
I also eventually purchased a t-ring and an adaptor from Amazon to be able to use my Canon D350 digital SLR camera to take photos, which is great fun but which requires you to take a lot of care to be able to produce half-decent results, even for something as big and as bright as the moon (see the attached photo). It is fun and a real challenge to try to spot and photograph the thinnest possible (hours rather than days old) crescent moon (so tricky I haven't yet managed it).
I have also purchased a Celestron X-Cel LX 12mm - 1.25 inch eyepiece (from Amazon UK - about £60) for the scope, which gives a very wide field of view and allows me to view easily with my glasses still on. It provides a clearer and brighter view of whatever you are looking at - and is, just about, worth the extra money.
In any case, I wish you clear skies and good luck!