The new "IntelliScopes" now use Altitude (up/down) and Azimuth (left/right) sensors built into the dobsonian base and main altitude pivot, and these have high-resolution 9,216 step digital-encoders which communicate with a compact computer module that displays arrows showing you which direction to "push" the scope (there are no motors, just you pushing the scope lightly) to the necessary alignment to view any of the night-sky objects contained in its 14,000+ object database; stars, planets, clusters, nebulae, galaxies, using the various astronomy catalogues, e.g. Messier and NGC.
Cleverly it also allows you to point the scope at an unknown object and identify it, and it also allows you to create up to 99 of your own custom defined sky locations.
The IntelliScope system will also take you on 12 monthly "tours" through the year, showing the best sights visible in each month. This in itself is a great way to learn your way around the night sky, if you are unfamiliar with constellations and the various celestial prizes lurking in their depths.
The buttons on the unit are white translucent rubberised material which are backlit. The main power button is also used to change the brightness of the backlight. Sometimes the Power button seems to stick in its cutout, but otherwise the buttons seem fine to use.
The Azimuth sensor is included as standard with the basic scope (because it forms part of the azimuth central axis pivot bearing), but this sensor is inactive until you buy the (opional) IntelliScope Computer Object Locator, which provides the extra Altitude sensor disc parts and all cables required to operate the system.
Even better, if you buy another (optional) RS232 Serial cable (or make one yourself) you can connect from the IntelliScope computer object locator into the serial port of a nearby personal computer or laptop.
Several popular astronomy software packages (e.g. Carte du Ciel [free] or The Sky 6) can be used to track where you are pointing the scope (some software may require an ASCOM driver - Astronomy Common Object Model). They will show on their star charts the exact region of sky the scope is centred on. So now you have two methods for finding things; the Object Locator, or your laptop with astronomy software.
The Object Locator unit can be mounted in an (optional) metal holster bracket which attaches to the side of the main dobsonian base, although I think it is a little expensive for what it is (however I paid for it).
Some folk have used velcro strips fixed to the OTA tube itself to mount the computer module, but I found that it is easier to view the LCD display held in-hand while locating objects (parrticularly if you have the display set at its lowest brightness), and once positioned I place it back in the bracket. I think it would be an annoyance to continually be pulling it away from the velcro, and sticking it back on, since this might also move the scope off-track.
The LCD display (and backlit buttons) have 5 different brightness settings so you can dim the light so as not to upset your dark-adapted eyesight (pressing the power-button repeatedly cycles thru the brightness settings).
On freezing cold nights the LCD display can become a bit "slow" to update (this is a general disadvantage of LCD displays), but this can be remedied by keeping the object locator indoors until you are ready to use it, separate from the main telescope which you would normally store in a cooler location such as a conservatory, shed or garage. (Some people have even made a small electronic modification using small high wattage resistors behind the display, which an external low-voltage supply powers, to act as little heaters - just sufficient to ease the slowness).
The Object Locator is powered by a standard 9volt PP3 battery, and this will last about 50 hours. The unit turns off automatically if no buttons are pressed. If it turns off, you will have to repeat the alignment procedure. On early models (pre Feb 2005) this was a very short 15 minutes, which can easily pass when you are totally absorbed by the view at the eyepiece! This was changed to a more lenient 50 minutes.
Initialising the IntelliScope to align it with the telescope and current night-sky conditions is simply a matter of turning the computer On, then selecting the POINT VERTICAL option (make sure you do not select the ALIGN DEC MARK option) then pointing the scope tube up until it hits a vertical stop (set accurately just once when you first assembled the scope), then hit Enter.
Next, using the Finder Scope and a low, then medium, magnification eyepiece you point the scope at just one of several bright stars you can select which are listed by the computer (maps are provided in the manual to help you). You centre this 1st star as best you can. Hit Enter, and repeat for a 2nd star more than 60 degrees apart from the first. Hit Enter again, and it will briefly show the "Warp Factor", a magic number which indicates how accurately you performed the alignment. Now you're ready to go.
There is no need for the scope base to be absolutely horizontal. As long as it is roughly level on firm ground it will be fine.
The important part is the setting of the scope tube perfectly vertical using a spirit level when you first build the scope, i.e. it must have a reference exactly 90 degrees from the fixed horizontal base. So make sure for this that you do it on perfectly level ground, e.g. in your house or workshop.
The computer will account for how "off-level" the whole telescope is on slightly uneven ground when you do the alignment, because then it is "looking" at the real positions of the stars. Obviously if you accidentally move the base, or if it sinks into soft ground, you may have to re-align again.
For most objects even a rough star alignment works quite well and will place the desired object in the field of view of a low magnification eyepiece. After identifying and centreing visually, you can increase the magnification to observe more closely.
The first few times you align will be slow, but once you are familiar with the procedure, and are used to locating a couple of "favourite" bright stars you can have the alignment done in 3 or 4 minutes. I usually align first with Mizar in Ursa Major (The Plough or Big Dipper), and second with Betelgeuse in Orion The Hunter. This is quick compared with the polar alignment procedure involved with many Equatorial Mounts. Indeed you can carry the scope outside, prepare everything, align the scope and be observing in just 10 minutes if you are quick!
If you intend to observe objects that are dim and not so easily identified in the star field, and therefore are relying more on the computer to give an accurate position, this may require more care for the initial star alignment procedure (i.e. try to get a lower Warp Factor), possibly by using an illuminated reticule eyepiece (crosshair/grids engraved into the eyepiece lenses and lit by an adjustable brightness LED) to aid more accurate centreing of the alignment stars. A better warp factor will then ensure that difficult to see objects are accurately centred.
Other Topics in this XT10 Review: