Orion Skyquest XT10i Intelliscope Newtonian Reflector Telescope on Dobsonian Mount
A close encounter with the Orion XT10i Newtonian Dob with Intelliscope Object Locator
Warning: Setting expectations in Astronomy!Have you ever looked through a telescope? If not, please take note.....
Let me give you a little warning to dispel some myths, and set your expectations to prevent disappointment if you are seriously considering buying a telescope......
If you are expecting to see wonderful vistas of nebulae or galaxies surrounded by beautiful delicate veils of colourful nebulosity like you have seen in astronomy magazines or on the TV then listen very carefully.
The truth is that those glorious photos involve very long exposure times, multiple images added together with special software to improve contrast and colour depth, and using cameras that are far more sensitive than the human eye.
With the naked eye, yes, you can see wispy details in prominent DSO's (e.g. the Orion nebula can even be seen without a telescope or binoculars), but for faint ones, unless the sky conditions are very good, even with a decent telescope they will often appear as a dim, hazy smudge or blur!
At certain times of the year (especially in damp, dreary old United Kingdom), and cruelly usually coinciding just after Christmas when many people buy or receive telescopes as gifts, even on apparently clear nights when you can see some stars, the skies can be quite terrible for viewing even the dimmer stars, let alone nebulae and galaxies! Take heart - later in the year, when the weather becomes drier and the jet-stream stabilizes, views will improve dramatically (more is explained in the sections on Transparency and Seeing in just a moment).
Nebulas and galaxies are very faint objects. And yet besides the moon and planets, many deep-sky objects can be seen from light-polluted skies! A 200mm Newtonian reflector such as the XT8i (the XT10's smaller brother) will allow you to seek out as many DSO's as you can for a given amount of money.
In daylight the human eye uses a region of the retina called the fovea, which is densely populated with "cones" that are colour sensitive, but they require high light levels to work well. Stars and Planets can often be seen in colour because they are relatively bright points of light.
Section through the human eye and retina.
In contrast the more sensitive "rods" are not colour sensitive and only see in monochrome. That's right - BLACK and WHITE. And this is why DSO's that can have beautiful colours when imaged photographically, tend to appear as shades of grey when viewed through a telescope. Away from the central region, the cones are fewer in number, and the rods are more densely packed. This is why you can see fainter objects by using "averted vision" - this is done by directing your gaze slightly to one side of the object of interest, a technique used by astronomers.
Try this the next time you go outside to look at the stars, look directly at a region of stars, then look to the side while still concentrating your vision on the same area of sky. You will notice the area away from your central vision can detect much fainter points of light. This can be used to advantage when looking through a telescope eyepiece. Also because you are moving your eye slightly, this creates movement of the light source which makes the faint stars more noticeable to your eyes.
Depending on several factors, i.e. where you live in the world, the time of year, use of a dark viewing location free of light-pollution, the "seeing" and "transparency" of the night sky, how good and dark-adapted your eyes are, it is possible to see colour in DSO's under exceptionally good conditions as long as your scope has sufficient light-collecting ability to trigger your cones.
The more aperture you have, the more light the telescope gathers.
When you first go outside into the dark, your pupils dilate in about 20 seconds, and very soon you will see fainter stars. Our second dark-adaptation mechanism takes about 30 minutes to come into effect. Without bright light on the retina, vitamin A is converted into retinene, then rhodoposin (visual purple) which significantly improves the sensitivity of the rods and cones.
But strong white light rapidly reverses this change, while red light is far less damaging, and this is why you should take every precaution when star gazing to use a red LED torch, or cover a torch with red celophane. If you plan on using a laptop computer near your telescope, cover up all white or blue LED's with red insulating tape, adjust the brightness of the monitor to its minimum, and set the computers colour theme to be predominantly red. Many astronomy software packages have a red or "night-mode" display option.
When I first got my XT10i, and once I had got everything set up correctly, during December while the night skies were quite good, I discovered just how much I could see with this scope. The Orion Nebula is quite an amazing sight. Through my 25mm eyepiece and 2xBarlow the main nebula fills the entire view, and it is fantastic to see the wispy veils, and the "Trapezium" - the four bright stars at its centre.
Star Clusters are another thing of beauty which I was mesmerized by. Looking at the thousands of stars so closely packed together in such a small part of the sky is just awesome. These are things I had never seen before, and seeing them yourself, in the flesh so to speak is quite remarkable.
When I viewed Saturn for the first time I couldn't believe not just the clarity and its stunning rings around it, but also the fact I could make out the moons circling Saturn.
The Leo Triplet was another nice discovery using the Tours feature of the Intelliscope, when it showed me three distant galaxies in close proximity to each other, so that you can see all 3 in a wide-angle eyepiece at once.
Not to mention the Moon. So incredibly bright (use a moon filter), and once focused on the surface, and using the standard 10mm EP plus the Barlow, position the view at the leading edge of the Moon and let it slowly traverse your view. You really feel as though you are flying in a spaceship just above the moons surface.
Another thing which surprises me often, is how I can look up at the sky and think "Is it good enough to get the scope out tonight?". There will be some stars out, but mainly the brighter ones, so I think hmmm, maybe not worth it tonight. But then I remind myself that I have paid good money for this piece of kit, so I set it up. With just the basics I can be viewing in about 10 minutes, probably shorter if I don't have to wrap up warm. The surprising part is just how many more stars become apparent with the XT10.