Cloudy's Skywatcher Maksutov 102/1300 Avant website

by Claudio Di Veroli

Star Watching

Pointing the SkyMax-102 AV at a Sky Object

More advanced/larger mounts can either be turned around so that their coordinate scales follow a given set of values, or else they can be pointed electronically or via a computer. None of these alternatives is available with the Avant mount, which has no coordinate scales. What you need to do is to select the proper finder, and then follow one of the pointing methods detailed below.

TELESCOPE MOUNTING

With your tripod and mount duly Polar-Aligned (see our Polar Alignment webpage), you can now rotate both knobs (Declination and Right Ascension) to point to the region of the sky you are going to view. At this point you will find that, without moving the tripod and mount, you can turn around the mount knobs, and the telescope in its attachment to the mount, so that that the telescope is either “to the left” or “to the right” of the mount's/tripod's centre: you should select the position that provides the best comfortable use of the finders, which will be mostly “to the left” of the mount when looking at the North and West, and mostly “to the right” of the mount when looking at the South and Est. In other words, you position the telescope so that the finder mount(s) are as much as possible on top, not on the bottom (which would make the use of the red-dot finder uncomfortable and the use of the finderscope impossible). Lots of words, but actually very easy to learn with a minimum of practice.

FINDER SELECTION

POINTING METHODS

 

      

Location, Location, Location ...

A well-known mantra among amateur astronomers is that the quality of the location is more important than the quality of the telescope. If you are lucky enough to live (or to have a place to go) far from city lights, and on clear nights you can watch in awe the Milky Way and thousands of stars, you have all the time in your life to run a good software package to learn about the visible Universe, and to find out what your SkyMax can do and what it cannot.

However, most of us live in—or near to—cities and towns. Even living in the outskirts of a relatively small place, such as an European small province capital, is enough for the night lights to delete almost everything from the night sky: other than Moon and planets, you can hardly see more than a few dozen stars! Even Polaris, traditionally used for centuries by seafarers as North Pole indicator, can be quite difficult to spot. At this point there are two alternative uses for your SkyMax-102, according to whether you are in town or out in the countryside (or better up in the mountains): these alternatives are treated separately below.

Please note that the diameters below are expressed in millimetres: they represent apparent approximate sizes, equivalent to seeing a real object at about 40cm from your eyes.

Town and City

Moon. With a 25mm or a 14mm eyepiece you will see the full Moon beautifully enlarged. With a 14mm or a 9mm eyepiece you will be able to see details of craters. They show in particularly good detail and relief when the Sun illuminates them laterally: this happens in the “terminator”, the zone that separates the part of the Moon illuminated by the Sun from the dark part. Watching the same crater on consecutive days with different angles of solar light is a very interesting activity. Astrophotography is also particularly easy with the Moon (see our picture).

Venus. At the maximum magnification you can achieve with the SkyMax-102 (see our Resolution/Magnification webpage) you will see a white circle with an apparent diameter of about 7mm (variable during the year). Venus is permanently covered by bright clouds, and you will not see any surface details. However, it has phases like the Moon: therefore most of the time rather than a circle it shows interesting moonlike shapes such as crescents and gibbous. The picture shows my reconstruction of what I saw with an 8mm eyepiece at sunset in August 2018, when Venus was exactly at a “first quarter”.


Mars. Its apparent size varies greatly with the relative positions of Earth and Mars in their orbits. When they are farthest you can hardly spot Mars with the naked eye. But every 26 months they are nearest: Mars is said to be in “opposition” because the Sun is on one side of the Earth and Mars on the opposite side. At this point Mars becomes for a few weeks the brightest sky object after the Moon, and with our telescope we can enlarge Mars up to an apparent diameter of 8mm (at 200x). Often, however, Mars has severe dust storms that largely blur away the surface details, and the telescope just shows a featureless bright orange circle. In 2018 the visuals with our telescope looked hopeless, but “stacking” hundreds of frames obtained with our CMOS Camera (see our Astrophotography webpage) we were able to get the detail shown in the picture. [Please note that others amateurs have published much better pictures, but they were obtained with larger telescopes and long-exposure through motor-driven mounts.]

Jupiter. It also varies in apparent size like Mars, but having an orbit much larger than the Earth, the relative distance undergoes much smaller variation. Jupiter is also the largest planet in the solar system and therefore, in spite of the large distance, at 200x it looks actually larger than Mars in opposition: expect an apparent diameter of around 12mm. Especially during those months—in recent years in summer—when Jupiter is nearer to the Earth and raising high over the horizon, therefore less affected by earth atmosphere's thermal disturbances, with the SkyMax-102 you can see it as a bright circle with two or even three slightly coloured cloud bands. You can also see near to the planet—as bright spots—a few of its largest and nearest moons. Interestingly, Jupiter's moons move quite fast: go back to the telescope two hours later and their relative positions will have changed significantly. After the Moon, watching Jupiter is decidedly the most interesting use of this telescope. The picture was obtained in 2021 by —"stacking" frames obtained with our CMOS Camera (see our Astrophotography webpage).

Saturn. Its apparent size undergoes little change over time. Smaller than Jupiter and much farther away, at 200x it looks like a white circle with a diameter of about 6mm. You look for the Saturn rings and you find indeed that the planet is surrounded by a white ring: you can clearly see (as black crescent shapes) the two separations between the planet and the ring. The picture reproduces what I saw in August 2018 with this telescope and an 8mm eyepiece. The sensitivity and magnification were not enough to show the Cassini division: for this you probably need a larger telescope. [A user has seen it with a SkyMax-102, but he was in the unpolluted skies of countryside Romania.]

Comets. Quite infrequently a few comets become visible, some of them even to the naked eye. Sometimes for a few days, with an amateur telescope, you can even see a tail. Watch for news online.

(no nebulae!). Do not even try with nebulae from city-light polluted places, or even in the darker-sky of the nearby countryside. I drove a few miles West from Lucca to a dark countryside spot, where the sky looked mostly quite dark. The clusters in Perseus (NGC 869 and 884) were not too difficult to spot, although I could only see a few of their brightest stars. As for the largest and brightest of the Messiers objects, M31 Andromeda Galaxy, I could not see it at all with the naked eye, though it was not difficult with binoculars and finderscope to spot it ... as a faint blurry blob! I then pointed at it the telescope with the low-magnification-high-luminosity 25mm eyepiece. The pictures below show, left-to-right, a professional-telescope long-exposure picture, what I expected to see with my telescope and what I actually saw (not my astrophotography, but my deduction using different computer programs).

    

Terrible isn't it? So let us go to the countryside and up the mountains!

Countryside and Mountains

Searching for a good location. Unless you have holidays up in the mountains, if you live in a town or city it is often not easy to find a good location with really dark night skies. If you are ready to go up the mountains, find about a place accessible by car with an unobstructed view, and this is easier said than done. Ask local astrophiles and then expect weeks of trial and error until you find—with good luck—a good dark-sky location not too far from home. Let us now review what you can see once you get there.

Some places in Europe are highly inhabited and light-polluted: here in Italy we have very bad offenders, such as the zones around Rome and Naples, the Northern Po valley and the upper-Tuscany ring from Pisa to Florence. In North-West Tuscany a popular location among amateur astronomers is the Parco dell'Orecchiella, alt. 1200mt, near to a mountain top, with a place the size of half a football field with no trees. However, perfect it is not: a hill blocks the view towards the North and Northwest, while valley lights spoil the low view towards the South. And to get there from any place from Pisa to Florence you have to drive about two hours, half of it through mountain roads. Other places known by local astrophiles are near Abetone, alt. 1500 to 1900mt with almost unobstructed view, yet the sky at low altitude is still visibly light-polluted by large Northern Tuscany cities a few tens of kilometres away.

Solar system improvements. Against a dark sky the Venus phases show very neatly. Mars unfortunately did not show any improvement, not even in 2020 when the opposition was at a very good altitude. Jupiter may show one band more than usual. Saturn shows more moons. [Uranus and Neptune are very hard to find: either of them requires the maximum magnification supported by our telescope to tell them from faint stars.]

Deep-sky objects you should see. As I said above, do not expect miracles watching deep-sky objects with a small amateur telescope: even objects that look very bright in published pictures (obtained with long-exposure photography) in real life look quite faint when we watch them through an amateur telescope, and are therefore quite difficult to find using our manual mount and sky maps. With some patience, and during the time of the year that the object is visible from your latitude, from the Northern Hemisphere I have been able to find and watch clearly—albeit dimly!—the following Messier objects:

If your goal is watching relatively large but dim deep-sky objects (rather than relatively small but very bright planets), especially under less-than-ideally-dark skies, instead of the SkyMax Maksutov 102/1300, devised for high magnification but less luminosity (f=1300/102=12.7) you should get a similarly-priced Newton telescope with something like 150/650 (f=650/1250=4.3): it will have half the magnification but three times the luminosity.

More Messier objects under ideal conditions. With a new Moon, unpolluted and very dark skies, optimal accessories, skill, experience and luck, some amateur astronomers (but not myself!) with similar telescopes have watched few other darker objects (down to magnitude 7) such as M17 Omega Nebula, M33 Triangle Galaxy and M42 Orion Nebula, down to almost magnitude 8, but unless you are in the very darkest skies and are very lucky, you should not expect to see them—let alone find them!—with this telescope and mount.


                                     Copyright © 2021 Claudio Di Veroli. All Rights Reserved.