EXPLORE SCIENTIFIC DOB1045C 10 Inch Truss Tube Dobsonian Telescope Instruction Manual
- June 9, 2024
- EXPLORE SCIENTIFIC
Table of Contents
10 inch Truss Tube Dobsonian Telescope
Instruction Manual
Item #: DOB1045C
DOB1045C 10 Inch Truss Tube Dobsonian Telescope
10” Dobsonian Instructional Video Available Scan QR Code or Visit: youtu.be/jEZEipdok30
Problem?
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Call us:
1.866.252.3811
Our customer service experts will answer any question.
Monday – Friday; 8am – 5pm CST Or visit our online Customer Service Center
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WARNING:
This product can expose you to lead, which is known to the State of California
to cause cancer and birth defects or other reproductive harm.
For more information go to
www.P65Warnings.ca.gov.
WARNING:
The lens contains lead that may be harmful.
Wash hands after touching.
WARNING:
Contains button or coin cell battery.
Hazardous if swallowed — see instructions page 2.
WARNING:
SUN HAZARD — Never look directly at the sun with this device.
DO NOT USE THIS TELESCOPE OR ANY ACCOMPANYING FINDER SCOPE TO LOOK AT OR NEAR
THE SUN UNLESS YOU ARE USING A SPECIAL SOLAR FILTER! EVEN MOMENTARY VISUAL
CONTACT WITH THE SUN’S LIGHT RAYS CAN INSTANTLY CAUSE IRREVERSIBLE DAMAGE TO
YOUR EYE(S). EYE DAMAGE CAN BE PAINLESS, SO THERE IS NO WARNING TO THE
OBSERVER THAT DAMAGE HAS OCCURRED UNTIL IT IS TOO LATE. TAKE EXTRA CARE WHEN
USING THE TELESCOPE OR A FINDER SCOPE DURING DAYLIGHT HOURS, AND DO NOT POINT
EITHER AT OR NEAR THE SUN. DO NOT LOOK THROUGH EITHER WHEN YOU ARE MOVING THE
INSTRUMENTS DURING THE DAYTIME. NEVER ALLOW ANYONE TO USE THE TELESCOPE OR A
FINDER SCOPE DURING THE DAYTIME WITHOUT WARNING THEM OF THE HAZARDS OF AIMING
EITHER AT OR NEAR THE SUN. MAKE SURE THAT THEY ARE ADEQUATELY TRAINED ON THE
USE OF THESE INSTRUMENTS BEFORE ALLOWING THEM TO START OBSERVING. CHILDREN
SHOULD ALWAYS HAVE INFORMED AND TRAINED ADULT SUPERVISION WHILE OBSERVING.
IMPORTANT SAFETY INSTRUCTIONS READ AND FOLLOW THE INSTRUCTIONS BEFORE USE. KEEP THESE INSTRUCTIONS FOR LATER USE.
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SUN WARNING: WARNING – NEVER ATTEMPT TO OBSERVE THE SUN WITH THIS DEVICE! OBSERVING THE SUN – EVEN FOR A MOMENT – WILL CAUSE INSTANT AND IRREVERSIBLE DAMAGE TO YOUR EYE OR EVEN BLINDNESS. EYE DAMAGE IS OFTEN PAINLESS, SO THERE IS NO WARNING TO THE OBSERVER THAT THE DAMAGE HAS OCCURRED UNTIL IT IS TOO LATE. DO NOT POINT THE DEVICE AT OR NEAR THE SUN. DO NOT LOOK THROUGH THE DEVICE AS IT IS MOVING. CHILDREN SHOULD ALWAYS HAVE ADULT SUPERVISION WHILE OBSERVING.
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RESPECT PRIVACY: WHEN USING THIS DEVICE, RESPECT THE PRIVACY OF OTHER PEOPLE. FOR EXAMPLE, DO NOT USE IT TO LOOK INTO PEOPLE’S HOMES.
-
CHOKING HAZARD: CHILDREN SHOULD ONLY USE DEVICE UNDER ADULT SUPERVISION. KEEP PACKAGING MATERIALS LIKE PLASTIC BAGS AND RUBBER BANDS OUT OF THE REACH OF CHILDREN AS THESE
MATERIALS POSE A CHOKING HAZARD. -
RISK OF BLINDNESS: NEVER USE THIS DEVICE TO LOOK DIRECTLY AT THE SUN OR IN THE DIRECT PROXIMITY OF THE SUN. DOING SO MAY RESULT IN A PERMANENT LOSS OF VISION.
-
RISK OF FIRE: DO NOT PLACE DEVICE, PARTICULARLY THE LENSES, IN DIRECT SUNLIGHT. THE CONCENTRATION OF LIGHT RAYS COULD CAUSE A FIRE.
-
DO NOT DISASSEMBLE THIS DEVICE: IN THE EVENT OF A DEFECT, PLEASE CONTACT EXPLORE SCIENTIFIC CUSTOMER SERVICE DEPARTMENT AT 866.252.3811.
-
DO NOT SUBJECT THE DEVICE TO TEMPERATURES EXCEEDING 60 °C (140 °F).
-
DISPOSAL: KEEP PACKAGING MATERIALS, LIKE PLASTIC BAGS AND RUBBER BANDS, AWAY FROM CHILDREN AS THEY POSE A RISK OF SUFFOCATION. DISPOSE OF PACKAGING MATERIALS AS LEGALLY REQUIRED. CONSULT THE LOCAL AUTHORITY ON THE MATTER IF NECESSARY AND RECYCLE MATERIALS WHEN POSSIBLE.
-
**** THE WEEE SYMBOL IF PRESENT INDICATES THAT THIS ITEM CONTAINS ELECTRICAL OR ELECTRONIC COMPONENTS WHICH MUST BE COLLECTED AND DISPOSED OF SEPARATELY.
-
NEVER DISPOSE OF ELECTRICAL OR ELECTRONIC WASTE IN GENERAL MUNICIPAL WASTE. COLLECT AND DISPOSE OF SUCH WASTE SEPARATELY.
-
MAKE USE OF THE RETURN AND COLLECTION SYSTEMS AVAILABLE TO YOU, OR YOUR LOCAL RECYCLING PROGRAM. CONTACT YOUR LOCAL AUTHORITY OR PLACE OF PURCHASE TO FIND OUT WHAT SCHEMES ARE AVAILABLE.
-
ELECTRICAL AND ELECTRONIC EQUIPMENT CONTAINS HAZARDOUS SUBSTANCES WHICH, WHEN DISPOSED OF INCORRECTLY, MAY LEAK INTO THE GROUND. THIS CAN CONTRIBUTE TO SOIL AND WATER POLLUTION WHICH IS HAZARDOUS TO HUMAN HEALTH, AND ENDANGER WILDLIFE.
-
IT IS ESSENTIAL THAT CONSUMERS LOOK TO RE-USE OR RECYCLE ELECTRICAL OR ELECTRONIC WASTE TO AVOID IT GOING TO LANDFILL SITES OR INCINERATION WITHOUT TREATMENT.
BUTTON/COIN BATTERY WARNING: THIS PRODUCT CONTAINS A BUTTON OR COIN CELL BATTERY. A SWALLOWED BUTTON OR COIN CELL BATTERY CAN CAUSE INTERNAL CHEMICAL BURNS IN AS LITTLE AS TWO HOURS AND LEAD TO DEATH. DISPOSE OF USED BATTERIES IMMEDIATELY. KEEP NEW AND USED BATTERIES AWAY FROM CHILDREN. IF YOU THINK BATTERIES MIGHT HAVE BEEN SWALLOWED OR PLACED INSIDE ANY PART OF THE BODY, SEEK IMMEDIATE MEDICAL ATTENTION. -
A SWALLOWED BUTTON OR COIN CELL BATTERY CAN CAUSE INTERNAL CHEMICAL BURNS IN AS LITTLE AS TWO HOURS AND LEAD TO DEATH DUE TO CHEMICAL BURNS AND POTENTIAL PERFORATION OF THE ESOPHAGUS.
-
DISPOSE OF USED BATTERIES IMMEDIATELY, FLAT/DRAINED BATTERIES CAN STILL BE DANGEROUS
-
KEEP NEW AND USED BATTERIES AWAY FROM CHILDREN.
-
IF YOU THINK BATTERIES MIGHT HAVE BEEN SWALLOWED OR PLACED INSIDE ANY PART OF THE BODY, SEEK IMMEDIATE MEDICAL ATTENTION.
-
IF YOU SUSPECT YOUR CHILD HAS SWALLOWED OR INSERTED A BUTTON BATTERY IMMEDIATELY CALL THE POISONS CONTROL HOTLINE AND SEEK IMMEDIATE MEDICAL ATTENTION.
-
EXAMINE DEVICES AND MAKE SURE THE BATTERY COMPARTMENT IS CORRECTLY SECURED, E.G. THAT THE SCREW OR ANOTHER MECHANICAL FASTENER IS TIGHTENED. DO NOT USE IF COMPARTMENT IS NOT SECURE.
-
TELL OTHERS ABOUT THE RISK ASSOCIATED WITH BUTTON BATTERIES AND HOW TO KEEP THEIR CHILDREN SAFE.
All Explore Scientific telescopes and telescope accessories are subject to constant technical improvement. Minor changes of product specifications that happen during the improvement of the product are subject to change without notice.
Telescope Parts Overview
Parts List
1. Secondary mirror assembly
2. Focusing unit
3. Collimation tool
4. Tube trusses
5. Mirror box lid
6. Altitude wheels| 7. Rocker box
8. Alignment Clutch System
9. Mirror box
10. Viewfinder holder
11. Red dot finder
12. Tension latch
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Additional Parts (not shown):
Hex screws w/ sleeves and thumb screws for altitude wheels
Moon filter
Planisphere
Moon Map
25mm extension tube (all ready installed)
20mm extension tube
Recommended accessories that are not included: Counterweights (sold separately; contact customer service at 1-866-252-3811 for more information)
Unboxing and Checking Contents
Please Note: We recommend that you keep the original shipping box and packing materials if possible, in case your scope should ever need to be returned for service or warranty purposes.
Inside the main package, you will find:
– Two altitude wheels
– Altitude wheel box
– Red dot finder
– Secondary mirror assembly with finder bracket and 2-inch focuser
– 4 pairs of trusses
– Collimating tool for the main mirror
– Main mirror box
– 8 Screws:
- 4 short screws with knob to secure the secondary mirror cage to the truss pairs
- 2 long screws with knob to secure the altitude wheels directly to the main mirror box itself
- 2 long thinner screws with knob to connect the altitude wheels to the lid of the main mirror box
– 1 inch focuser extension
– 2 Alignment clutch systems
When you open the box, the first thing you will find are the trusses, Figure
2:
Figure 2
The trusses are already assembled in four pairs, Figure 2. You will also find the collimation tool for the main mirror of the telescope. Carefully remove the parts from the box, unwrap them and remove the foam parts that secure the rest.
After removing the trusses, you will find two boxes, Figure 3. The smaller one
contains the mirror box and the other contains the rocker box. On the outer
left you can see one of the altitude wheels. Remove all parts from the box and
unwrap everything. When you open the lid of the mirror box you will see the
following setup:
Inside the mirror box, Figure 4, you will see a foam insert that contains some
small parts, 2x barlow, digital eyepiece, clutches, 20mm extension tube and
the red dot finder. This foam insert also protects the main mirror during
transit.
It also gives you the opportunity to store/transport eyepieces or accessories.
Remove the insert and the protective paper from the main mirror but leave the
foam pieces surrounding the edges of the mirror in place to protect the
collimation system.
We recommend keeping the soft paper covering because it can protect the mirror
from dust and dirt without giving off fluff.
In the other box there is the secondary mirror cage unit and the rocker box:
Take both parts out of the box and carefully remove the protective paper from
the secondary mirror.
Assembly
We suggest reading all this manual in it’s entirety before attempting
assembly.
If you are assembling your telescope for the first time, we recommend doing so
in a climate-controlled room.
First, place the mirror box onto a table to attach the altitude wheels to the
mirror box. You will notice that each altitude wheel has two holes. One of the
holes matches the threaded hole on the mirror box, and the other matches the
threaded hole in the lid of the mirror box.
Important: You have two possibilities to attach the altitude wheel onto
the mirror box of the telescope.
There are two sets of holes on both sides of the mirror box. Having two sets
gives you an additional degree of freedom to balance your telescope. If you
are just using lightweight eyepieces (1.25 inch) we recommend attaching the
altitude wheels to the lower set of holes, Figure 5. If you are using a coma
corrector, heavy eyepieces or both we recommend using the upper set of holes.
Though the distance of the holes in the altitude wheels appears to be similar, the orientation of the wheels on the mirror box DOES matter – holes will not align if the altitude wheels are mounted in the wrong orientation.
Type of Screws
A: 2 long screws with knob to secure the altitude wheels directly to the main
mirror box itself
B: 2 long thinner screws with knob to connect the altitude wheels to the lid
of the main mirror box
C: 4 small knobs with screws to attached secondary mirror assembly
D: 2 HEX screws with sleeve
To screw the altitude wheels to the main mirror box, place the main mirror box
on a horizontally balanced table.
Screw each altitude wheel to the main mirror box using one long screw with
knob (A) and a HEX screw with sleeve (D) each. The HEX screws must be inserted
into the countersunk holes of the altitude wheels first, Figure 6. Use the
supplied hex wrench for mounting, Figure 7. Attach the altitude wheel through
the second hole using one long thinner screw (B) on the mirror box then the
third hole to the unfolded main mirror box top, Figure 8.
We recommend marking the position of the altitude wheels so that everything
works on the first try next time you assemble the telescope. We recommend
using luminescent paint or stickers that enable you to assemble the telescope
in complete darkness so your eyes can adapt to the night sky faster. These are
available from modelmaking sources.
Now look at the mirror box from above. You will see knobs and triangular
pieces sticking out from each corner of the mirror box. Loosen the knobs,
making sure that they don´t come off and fall onto the main mirror.
Unwrap the truss pairs. Each pair of trusses is connected by a metal bracket
that has a groove in it. Slide the bracket with the groove over the threaded
rod then tighten the knob to lock the truss in place. Do this for all four
trusses.
Important: After you have tightened the knobs the trusses will be secured
to the mirror box BUT they will still be able to swing freely from side to
side, which means they could bump into surrounding equipment or people if not
carefully monitored.
Important: During the attachment of the secondary mirror assembly make
sure that you have control of the secondary mirror assembly at all times. If
you are doing this for the first time you will need a few minutes to get
accustomed to the procedure. The help of a second person is suggested.
Separate the truss tube pairs until each tube meets the one next to it. This
creates a perfectly aligned hole that aligns with an attachment point on the
bottom of the secondary assembly.
The telescope is designed to have the focuser oriented on the right side, so
that the red dot finder is above the focuser when you move the telescope. To
determine the right side, stand facing the silver handle of the mirror box.
Turn the secondary mirror assembly so that the focuser is on the right.
Hold the secondary mirror assembly with one hand while you align the truss
holes and the threaded hole of the secondary mirror assembly. Once aligned,
insert the small knobs with screws (C) and partially tighten them. Be sure to
insert the screws from the outside of the secondary mirror assembly. It may be
helpful to use the lip of the truss tubes to steady the secondary mirror
assembly while inserting the screws.
Do not fully tighten the screws until all four screws are inserted correctly –
trying to force a screw into the threaded hole on the secondary assembly will
damage the thread. If assembled correctly, that screws will go into the
threads without the use of force. After all four screws are placed into the
threaded holes in the secondary assembly, tighten the screws being sure not to
over tighten.
Important: With the rocker box on the ground place the mirror box into
the rocker box. Do NOT use the trusses to pick up the mirror box.
Install a clutch on each side of the rocker box. To install, place the clutch
with the white tension pad facing the altitude wheel into the hole nearest the
end with the sliver handle.
Attach the clutch by screwing in the large knob until the tension pad presses
firmly against the wheel. The clutches enable the telescope to move up and
down but not slip.
Collimation
Collimating the optical systems
Although the optics in your telescope were carefully collimated in our quality
control department prior to leaving our facility, we recommend collimating the
telescope after reassembly. The whole procedure is straightforward and should
takes only a few minutes after reassembly, if you have numbered your trusses
and reassemble your telescope the same way it had been assembled.
The collimation of the telescope is done in three steps:
Rough Collimation
Collimating the secondary mirror:
If the telescope is collimated you should see the concentric images of your
eye, the secondary mirror, the main mirror and the focuser.
- Draw tube barrel
- Primary mirror
- 4 vanes of secondary mirror holder
- Secondary mirror
- Your eye
To test rough collimation:
- Remove the eyepiece from the focuser and look through the focuser draw tube. The secondary mirror should appear round. If the secondary mirror does not appear round, tilt it with the three collimation screws that are located on the back side of the secondary mirror holder.
- Next check the reflection in the secondary mirror of the middle point of the main mirror, which is marked by a tiny black doughnut on the mirror. If the reflection of the mark on the main mirror is not in the center of the secondary mirror, center it by using the three collimation screws.
Spider vanes (1); secondary mirror (2); focuser drawtube (3); focused image
(4).| Secondary Mirror Assembly (front and side view). Spider
vanes (1); tilt screws (2); secondary mirror holder (3).
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|
Adjusting the main mirror
Once the secondary appears round and the mark on the main mirror is centered,
check the collimation of the main mirror. If the reflection of your eye and
the reflection of the secondary mirror on the main mirror are not concentric,
insert the collimating tool into one of the collimation screws that are
located on each side of the main mirror, Figure 9.1. When you turn the
collimation tool you will notice that the hexagonal head of the tool will lock
into the hexagonal head of the collimation screw. Now you can adjust the main
mirror by turning the collimation tool, Figure 9.2. Adjust the screws until
the eye and the reflection of the secondary are centered in the main mirror.
Practice this until you get a feel of what a turn of one of the collimation
screws is doing.
Fine Collimation
NOTE: Please take care that the telescope has time to adapt to the
ambient temperature before starting collimation – this will need up to 30
minutes (otherwise you will not get a good star image). You may use the fans
to speed up this process.
During fine collimation, locate Polaris and view it with high magnification.
If the telescope is collimated well, you will see a system of dim rings of
light surrounding a central bright spot —the so-called airy disc. You will
also notice a dim cross of light coming from this airy disc. This is the
diffraction that is caused by the secondary spider vanes. We have left this
cross out of the next figures for clarity. What we want to
see is shown in Figure 12 – a central airy disc that is surrounded by
concentric rings. However, it is much more likely that the picture will be
different – more like Figure 10. It is essential that you always center the
star because outside of the optical axis all stars do show some distorted
images. Note: You will get those images only during moments of perfect steady
air because air turbulence will distort this image. However the collimation
goal remains the same – getting a concentric star image. So let us assume you
have good seeing and your eyepiece shows you something like Figure 10:
Try turning the main mirror collimation screws – when you are turning the
correct screw in the proper direction, you will notice that the distracting
“tail” is getting shorter (Figure 11):
Remember to recenter the star after you have turned a screw. When the
telescope is perfectly aligned, you will see the picture of Figure 12 (when
the air is perfect). During the use of your telescope you will get a feeling
for this – it does not make sense to spend a lot of time on collimation when
the air is moving too much.
Important: Outside the optical axis (the middle of the field of view) all
stars will be distorted and show tails directed to the edge of the field of
view. If you are using cheap eyepieces those star images will be even more
distorted because the off-axis aberrations of the telescope and the eyepiece
will add up. For this reason it is essential to recenter Polaris after every
turn of a collimation screw because the turning of the screw will also shift
the star from its centered position. As mentioned before it may not be
possible to get a sharp star image during periods of turbulent air. In this
case try to achieve a symmetrical image during collimation. If you don’t see
any more improvement abort the process. During nights of unsteady seeing it is
not recommended to use high magnification. Try to enjoy low magnification
objects like nebulae, clusters and galaxies on those nights instead of
fretting over the bad conditions.
Using Your Dobsonian
Your Explore Scientific Dobsonian is a precision optical instrument and should
be used with care. Try to avoid exposing your telescope to vibrations because
this may cause the telescope to lose collimation.
Aligning the viewfinder
The red dot that is used by the finder scope is not readily visible during the
day. For this reason you should align the finder scope once it is dark.
To do this:
- Insert an eyepiece with low magnification into the focuser of the telescope and make sure that the red dot finder scope has loaded batteries and is switched on.
- Look through the eyepiece and center an object that is easy to find at a minimum distance of more than 800 yards, like a street lamp.
- Look through the red dot finder and move your head until you see the red dot of light that is projected onto the glass window. Adjust the finder with the two screws until the red dot is on top of the object that is centered in the telescope’s eyepiece. You can fine-tune the finder collimation on a celestial object, like a bright star or a crater on the moon, by following the same procedure.
Focuser
The focuser of the Explore Scientific truss Dobsonian is a single speed
focuser.
Important: Never try to force the focuser beyond the stops. Do not turn the
focuser knobs while the focuser is locked. Turning the focuser knobs while the
focuser is locked
may result in damage to the focuser.
The telescope comes with two extension tubes, 25mm and 20mm tall. This is
needed so the eyepiece can focus. One 25mm extension tube comes pre-installed
and the
second 20mm extension tube can be added as needed depending on the eyepiece
magnification.
To install the 20mm extension tube, unthread the adapter and 25mm extension tube together from the draw tube. Thread the second extension tube onto the draw tube then thread the adapter and 25mm extension tube onto the second extension tube, Figure 13. Your included eyepiece can now be inserted to the 1.25in adapter by untightening the tension screw, sliding in the eyepiece and tighten the tension screw to tighten the compression ring lock, Figure 14.
Your telescope is compatible of using 2in eyepieces, sold separately, by
loosing the three tension screws from the tension collar and removing the
1.25in adapter.
Important: The tension collar is equipped with threads that will allow users
to attach a camera to the telescope.
However you will need a camera specific device called a T-ring (sold
separately) that goes between the tension collar and the camera.
Observing
Astronomical observations
The first observations should be performed during dusk so that you get
familiar with your new telescope quickly.
Always remember never to look at or near the sun! Choose a land object that is
easy to find and far away, such as a mountain top. Roughly point the telescope
at the object. Now look through the finder scope and move the telescope until
the red dot of light appears centered onto the object. If you are looking
through an eyepiece with low magnification, you should now be able to see the
object in the telescope. Focus the image carefully, center it in the field of
view and fine tune the alignment of the finder if necessary.
Moon
The Moon can be observed best during the periods where less than 50% of its
surface is bright. So you can see the detailed shadows that the sun is causing
when the light hits the craters from the side angle – creating a 3D-like
experience. We recommend using a neutral density filter for the Moon that
reduces the glare. During a Full Moon, the surface appears evenly bright
without contrast and prominent structures. If you are spending a few
successive nights watching the Moon you will notice the change in the
appearance of the mountains, craters and maria due to the change of the phase
of the Moon – a very interesting effect!
The planets
During their orbit around the sun the planets are continuously changing their
position on the sky. When they are visible, the following planets are
especially suited for observations with your telescope:
Venus:
The diameter of Venus is about 9/10 the diameter of the Earth, and it is the
third brightest object in the sky (after the Sun and the Moon). As Venus
orbits the Sun, you can observe the change of the light phases — sickle, half
Venus, full Venus — very much like the phases of the moon. The planetary disc
of Venus appears white because the
sunlight is reflected by a compact layer of clouds that covers all surface
details.
Mars:
The diameter of Mars is about half of the Earth’s diameter. In a telescope,
Mars will appear as a tiny red-orange disk.
You may see a tiny white patch when you look at the polar regions that are
covered in ice. About every two years, when Mars and Earth reach their closest
distance you can discover new features.
Jupiter:
The biggest planet in our solar system is Jupiter. In a telescope, the gas
giant appears as a disk that is covered in dark lines. Those lines are cloud
bands in the atmosphere of Jupiter. Even with low magnification, 4 of the 67
moons of Jupiter are often visible. These are the Galilean moons (Io, Ganymed,
Europa and Callisto). Because those moons
are orbiting Jupiter the visible number and position changes. Sometimes a moon
passes above the planetary disc of Jupiter – then the shadow of the moon can
be spotted on the planet as a sharp dark spot.
Saturn:
Saturn has a diameter about nine times the Earth’s diameter and appears as
small roundish disc with a distinct set of rings that bulge out from the edges
of the planetary disc. Galileo, who was the first human observer of this
planet in 1610, couldn´t know that the planet had rings. Instead, he described
Saturn as having “ears“. The rings of Saturn mainly consist of billions of icy
particles – ranging from tiny dust to the size of a house. The biggest
division in the rings, the so called “Cassini division” should be easily seen
with your telescope in nights of steady air. Titan, the biggest of the 62
moons of Saturn, is also visible as a bright, starlike object in the vicinity
of the planet. Up to six moons may be detected in your telescope.
Deep-Sky Objects
To locate constellations, stars or other deep-sky objects, it makes sense to
use a star chart. We will list a selection of deep sky objects here:
Stars are giant objects that mainly consist of gas. Due to the nuclear fusion
in their core they radiate energy and shine. The stars are extremely far away.
Because of this vast distance they appear as tiny spots of light in your
telescope, despite their size – no matter how big your telescope is.
Nebulae are giant interstellar clouds of gas and dust. Within those clouds new
stars are being born. The premier nebula on the northern hemisphere is the
Great Orion Nebula, a diffuse nebula that looks like a fuzzy patch of light in
the sword that branches off of Orion’s Belt. Also known as M42, it contains
many intriguing features that pop to life in a telescope.
An open cluster is a group of young stars that were born in a single diffuse
nebula not too long ago (on an astronomical time scale). The Pleiades is an
open cluster that is relatively young, having formed within the last 100
million years, and lies relatively close to Earth at about 440 light years
away. Found in the Taurus constellation, it consists of more than 1,000 visual
stars, although an average of only six are visible to the naked eye. A dark
sky free of light pollution can help a dedicated observer see around a dozen
Pleiades stars, but your telescope will quickly reveal many more of the
elusive members of this legendary cluster.
Constellations are big patterns of stars that were believed to be celestial
representations of men, gods and objects by old civilizations. Those patterns
are too big to be observed at a single glance through a telescope. If you want
to become familiar with the constellations, start with a pattern that is easy
to find, like the Big Dipper in the constellation Ursa Major. Try to locate
the other constellations in the neighborhood of this constellation in the
second step and move on to other patterns.
Galaxies are gigantic accumulations of stars, nebulae and clusters that are
held together by gravity. Most galaxies have a spiral shape (like for example
our own Milky Way galaxy), but there are also galaxies with elliptical or
irregular shapes. The closest spiral galaxy is the Andromeda Galaxy (M31). The
core of M31 looks like a bright patch of light in your telescope – under dark
clear skies you will be able to detect features in this object with your
telescope.
Hints and Tricks
Marking with luminous paint: As noted above in the section about assembly
it is very helpful to mark the positions of the altitude wheels and the
trusses. This helps when assembling the telescope at night and keeps
collimation issues at a minimum.
We also recommend marking your screws with a patch of luminous paint because
it makes finding lost parts a lot easier to find when dropped in the grass and
often makes it unnecessary to use a flashlight, which would ruin the night
vision of other observers.
Image orientation: You may have noticed that objects appear to be upside down
and mirrored in your telescope.
This is the case in almost every astronomical telescope and does not cause any
problem during astronomical observations.
Moving the telescope: Because of the Earth’s rotation all objects will
drift across the field of view. To compensate for this movement you have to
move the telescope smoothly and slowly. The higher the magnification the more
accurate this tracking movement has to be. Another solution is to place the
object on the eastern rim of the field of view and let it drift across the
field, then reposition it on the eastern rim again. However – this method only
works with good eyepieces that are delivering a sharp image up to the edge of
the field.
Vibrations: Try to avoid touching the eyepiece or telescope during
observations. This will cause unsteady views.
Night vision: Give your eyes some time to adapt to the darkness. This
takes about 20-30 minutes after an exposure to a bright light – even if it is
a short exposure. Use a dim light with a red filter to read star charts or
draw objects –dim red light does not influence your eye’s adaption very much.
Horizon viewing: Planets and other objects that are close to the horizon
are severely influenced by air movement.
It is much better to time your observations in a way that those objects are
close to the meridian (overhead), so that they are on their highest position
possible. If the image is dim or moving too fast to easily track, use a
smaller magnification. Using too much magnification is a mistake that is made
very often by beginners.
Warm clothing: Even in the summer the nights may get very cold during
clear nights, especially in the mountains.
Always remember to bring warm clothing — thick jackets, beanies, gloves,
winter shoes and thick socks — even if you were sweating during the day. It is
hard to enjoy even the best night when you are freezing!
Explore your observing site during the day: The ideal site should be far
off of frequently used streets and other light sources that would prevent your
eyes from adapting to the dark. Keep in mind that it is likely to get foggy in
the vicinity of open water, such as river valleys or lakes. The ground should
be solid and relatively flat. You can observe in the city, but try to get to a
place some distance away, where you can see the Milky Way if possible.
You can get really good conditions as close as 50 km outside of cities. If
relocating to a more rural area is not a possibility, try to position your
scope away from as many artificial light sources as possible. An old
astronomers quote says: “ You cannot really replace a dark sky by anything
other than a darker sky”
Calculating magnification
The magnification of a particular telescope configuration is determined by two
factors — the focal length of the telescope and the focal length of the
eyepiece. You will find the focal length of almost all eyepieces written on
the eyepiece body.
The magnification is determined by the following formula:
Magnification = Telescope focal length divided by eyepiece focal length
For example, for a 10-inch Dobsonian and a 20mm eyepiece: Magnification =
1270mm/20mm = 63.5x
The eyepiece type, like modified achromatic, Plössl or Super Plössl, does not
have any influence on the magnification, but determines other optical
properties like apparent field, chromatic error correction and flatness of the
field of view.
The maximum usable magnification is about two times the diameter of the
aperture in millimeters. However, in nights of bad to average seeing much
lower magnifications will produce a more detailed and steadier image. High
magnifications should only be used during periods of extremely steady air on
special objects, like double stars.
When you are starting to observe an object, always start with a low
magnification. Then center the object in the field of view and focus with
care. Now you can try a higher magnification. When the image is becoming fuzzy
or is moving too fast, go back to the last magnification. Atmosphere – and
thus seeing conditions – is always changing.
Please notice that a sharp image at a low magnification will show you more
than an over-magnified fuzzy view.
Service, Maintenance and Accessories
Your Explore Scientific truss Dobsonian is a precision instrument that will provide many years of fun. When you are treating this telescope with the same care as, for example, an expensive camera, it is very unlikely that you will ever need to return it for service or maintenance. For instructions on how to remove the primary mirror for cleaning call customer service at 866.252.3811.
NOTE: DO NOT USE AGGRESSIVE CLEANERS!
Do not use photographic lens cleaners and cloths that have been perfume
impregnated, colored or soaked with lotion, to clean any optical surfaces. If
using such cleaning agents, the optics can be permanently damaged!
Please note the following recommendations for maintaining your telescope:
-
Try to avoid cleaning the optics. Dust on the optical system will not deteriorate the performance of the optical system by any noticeable amount. Dust should not be a reason to clean the optics.
-
If cleaning the optics is necessary it is best to brush away the dust with a fine camel hair brush as it is used for photographic equipment. Do NOT use optical lens cleaning tissues as many contain fiberglass particles that can be abrasive.
-
Organic dirt (fingerprints etc.) can be removed from the optical surface with a mixture of 3 parts distilled water and one part pure isopropyl alcohol (99%). Only use soft, white, unscented, lotion-free tissues to wipe optics. Soak the primary mirror to dissolve the dirt and remove the fluid with short, cautious strokes. Remember to change tissues every few strokes. For instructions on how to remove the primary mirror for cleaning call customer service at 866.252.3811.
NOTE: NEVER REMOVE THE SECONDARY MIRROR! -
While you are using your telescope during the night you will eventually have dew condensing on the surfaces.
This will not cause any trouble – your telescope is designed to take a little moisture without problems. When you store the telescope, however, we recommend wiping the surfaces (except for the optics) with a dry cloth and giving the telescope some time to evaporate the water on the optics by putting the telescope into a dry room with the lid of the mirror box open. Wait until all water has dried off before storing the telescope.
Accessories:
Explore Scientific has a large portfolio of accessories available for your
telescope.
For a complete overview of these accessories, visit
www.explorescientific.com.
If you have any question regarding this product, please do not hesitate to
contact our Customer Service department at 866.252.3811 or at
https://explorescientific.supportsync.com. In case of the unlikely event
that your telescope needs service or repair at our facility, please contact
one of our customer service representatives before sending anything back. The
large majority of service issues can be dealt with on the phone without
sending anything back to us.
Specifications
10” Truss-tube Dobsonian Technical Specifications
Tube: | open truss design |
---|---|
Upper tube ring: | metal tubing including secondary spider and holder, plus |
focuser and truss connectors
Mirror box:| with main mirror and truss connectors
Trusses:| powder coated aluminum with connectors
Secondary spider:| 4-arm, steel
Main mirror:| 10 inch (254 mm), parabolic, aluminum coated with protective
layer, 94% reflectivity
Focal length:| 1270 mm
Focal ratio:| f/5
Focuser:| Single-speed
Mount:| Dobsonian
Finder:| red dot finder
Mirror box with mirror weight| 31.5 lbs.
Altitude box weight:| 12.5 lbs.
Secondary cage with secondary mirror weight:| 6.35 lbs
Truss tube (1 of 4) weight:| 1 lbs each
Total weight:| 54.35 lbs
© 2022 Explore Scientific, LLC.
1010 S 48th Street, Springdale, AR 72762
explorescientificusa.com |
exploreone.com | 866.252.3811
All rights reserved. Made in China.
References
- Explore Scientific Eyepieces, Telescopes, Microscopes & STEM Supply
- Explore Scientific Support
- Keep Exploring with Explore Scientific Telescopes, Microscopes, & STEM
- Keep Exploring with Explore Scientific Telescopes, Microscopes, & STEM
- P65Warnings.ca.gov
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