The Nexstar 5i is the computerized version of Celestron's legendary five inch Schmidt-Cassegrain telescope. Although I own larger telescopes, I find myself getting out the five inch SCT more than the others because it combines good optics with excellent portability and easy operation. The Nexstar 5i's optics are sharp enough to bring out pleasing detail on the Moon, on the planets, and on star clusters and galaxies, yet the optical tube is less than twelve inches long. It's small enough to carry outside (even when it's already set up ready to go), small enough to take on high desert camping trips, and easy to transport to public star parties. |
| The NextStar handset is your user-friendly guide to more than 40,000 celestial objects. |
What can I see with the Nexstar 5i? On a good night I like to use an optional Ultima 7.5mm eyepiece for a magnification of 166x. With the Ultima 7.5mm, I can see the Cassini division extending all the way around Saturn's rings. I've been able to watch the shadow of Jupiter's moons glide across the face of the planet, and sometimes the moons themselves. I can see the famous Great Red Spot on Jupiter (it's actually tan this year), and when Mars is favorably placed, I can see the polar cap and dark surface markings on Mars. From a dark viewing site in the country, I've been able to find all the Messier galaxies. When I look at M86 in the Virgo galaxy cluster with the standard equipment 25mm plossl eyepiece (about 50x), for example, I can see five galaxies at once, including M84 and three fainter NGC galaxies. When I look at brighter globular clusters like M13 and M22 with a 12.5mm plossl (100X) I can resolve many individual stars.The included Nexstar computer is much easier to use than earlier generations of computerized telescopes. You can choose from four different alignment modes, from the traditional two star alignment to the latest GPS-aided automatic setup using the optional CN-16 GPS module. I especially like the flexibility of the new "quick align" feature. I took two computerized telescopes to a recent public viewing session. Using the "quick align" mode I was able to set up the Nexstar 5i and start letting folks look at Venus a full half-hour before sunset! Meanwhile the older computerized telescopes, including my own, were waiting more than an hour before the first alignment stars appeared in the twilight.
The biggest drawback to the Nexstar 5i is the short life of its AA batteries. Low batteries can cause the Nexstar computer to crash and lose its alignment. I've been able to avoid these computer crashes by using Celestron's car battery adapter with a rechargeable jump-start power pack. Like all Schmidt-Cassegrain telescopes, dew forms easily on the front corrector lens, but Orion's #4209 Flexishield dew cap works well to prevent problems with fog on the lens. --Jeff Phillips
Pros:
- Proven optical performance of Celestron's five inch SCT
- Small enough to keep set up ready to go
- Nexstar computer is easy to use
Cons: Celestron's affordable, expandable NexStar 5i takes the best of the NexStar 5 to the next level of performance and operating features. This Celestron NexStar 5i also includes a special kit for adding a computerized hand control and a sturdy Celestron tripod. The highly advanced computerized hand control will transform your Nexstar 5i into a completely automated GOTO system. Just plug it in to access features like automatic star alignment capability, and GOTO provides slewing to over 40,000 celestial objects from its database of the complete Messier, NGC, IC, and Caldwell catalogs.
Reflectors | This is a reflector telescope. Reflectors (also known as Newtonian reflectors or catoptrics) capture light with a mirror at the bottom of a tube, which sends the image to the eyepiece at the top of the tube.
First-time telescope users sometimes have difficulty with the idea of looking through the side of a telescope, but the big draw for reflectors is that they are by far the cheapest to manufacture--and thus offer the best value--of all telescope types. They also generally have zero chromatic aberration.
Read more about different telescope designs in our buying guide |
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Equipped with the standard electronic hand control, you can manually slew your NexStar across the sky in seconds, or track a star equatorially as the Earth rotates beneath you. The electronic hand controls allows you to move the telescope at six different rates and has a "double button" feature that lets you instantly increase the slew speed without having to change rates.Some of the new features include an autoalign routine function, which guides you through a two-star alignment based on time, date, and location information; and the polar alignment routine function, enabling polar alignment for CCD imaging or conventional 35mm astrophotography.
Other features include:
- 127mm (5-inch) diameter Schmidt-Cassegrain refractor
- Focal length of 1,250mm and focal ratio of f10
- 6-degree per second slew speed
- Fully enclosed high-speed motors on both axes
- Integrated hand controller built into the side of the fork arm
- Auxiliary port for adding optional accessories
Moon viewing 101
The moon is often one of the first celestial objects a beginner will look at through his or her telescope. Here are a couple hints for you once you get your hands on your new NexStar 5i.
Often, it is tempting to look at the Moon when it is full. At this time, the face we see is fully illuminated and its light can be overpowering. In addition, little or no contrast can be seen during this phase. One of the best times to observe the Moon is during its partial phases (around the time of first or third quarter). Long shadows reveal a great amount of detail on the lunar surface. At low power you will be able to see most of the lunar disk at one time. The optional Reducer/Corrector lens allows for breath-taking views of the entire lunar disk when used with a low power eyepiece. Change to higher power (magnification) to focus in on a smaller area. Choose the lunar tracking rate from the NexStar's MENU tracking rate options to keep the moon centered in the eyepiece even at high magnifications.
Observing the Planets
Other fascinating targets include the five naked-eye planets. You can see Venus go through its lunar-like phases. Mars can reveal a host of surface detail and one, if not both, of its polar caps. You will be able to see the cloud belts of Jupiter and the great Red Spot (if it is visible at the time you are observing). In addition, you will also be able to see the moons of Jupiter as they orbit the giant planet. Saturn, with its beautiful rings, is easily visible at moderate power. Remember that atmospheric conditions are usually the limiting factor on how much planetary detail will be visible. So avoid observing the planets when they are low on the horizon or when they are directly over a source of radiating heat, such as a rooftop or chimney.
The Nuts and Bolts
- Optical Tube
- Star Pointer Finderscope
- Eyepiece
- Star Diagonal
- Focuser Knob
- Battery Compartment
- ON/OFF Switch / 12v power
- Fork Arm
- Hand Control
- Schmidt Corrector Plate (not shown)
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