Calculating Power:
Themagnicationofatelescopedependsonboththefocallengthofyour
telescope as well as the eyepiece you use. There is a simple formula you can
usetodeterminethemagnicationyouareusingatanygiventime.Simply
dividethefocallengthofthetelescopebythefocallengthoftheeyepiece.
For example, if you are using the 20mm eyepiece with your RP-200
telescope thepowerwouldbe:
Power = 500mm / 20mm = 25x
Usinganeyepiecewithasmallerfocallengthwillincreasethemagnication
ofyourtelescope.Itisalwaysbesttostartatthelowestmagnicationcon-
guration.Thewidereldofviewmakesiteasiertospotfarawayobjects.
Onceanobjectiscenteredinyoureldofviewyoucanswitchtothehigher
powercongurations.
UnderstandingCelestialMovement:
Inordertogetthemostenjoymentoutofyourtelescopeitisnecessaryto
knowthebasicsofhowcelestialobjectsmoveacrossthesky.Duetothero-
tationoftheearth,celestialobjectsappeartomovefromEasttoWestacross
thesky,muchliketheSun.Youwillnoticethismovementasanobjectin
yourtelescopeeldofviewwillslowlymoveacrosstheeldandoutof
view.Continuousadjustmentisneededtokeepanobjectintheeldofview.
Using the Telescope:
Onceyouhaveproperlyassembledandalignedyourtelescopeyouarenally
readytostartusingit.
• Tolocateanobjectusingthetelescope,rstloosenthealtitudelock
(Fig.3-20)allowingthetelescopetorotatealongbothaxes.Look
throughthenderscope(Fig.1-4)tosighttheobjectyouarelook-
ingforandcenteritinthenderscopecross-hairs.Youmayneedto
focusthenderscopebyturningthenderscopefocusknob(Fig.
4-22).Thenre-tightenthealtitudelock.
• Itisbesttousethelowestpowereyepiece(theKellner20mmeye-
piece)atrst.Thisallowsforawidereldofviewmakingiteasier
tolocateobjects.Oncetheobjectiscenteredintheeldofviewyou
canswitchtheeyepiecetohighermagnications.
• Oncetheobjectiscenteredintheeldofview,turnthefocusknobs
(Fig.1-6)untiltheimageisclearandsharp.Ifthefocusknobsare
locked,loosenthefocuserdrawtubelock(Fig.5-23)beforeturning
the knobs.
• Youwillnoticethattheobjectyouareviewingwillslowlymove
acrosstheeldofview(causedbytherotationoftheEarth).You
willneedtoturntheslowmotioncables(Fig.1-8,9)tokeeptheob-
jectcentered.
• Theorientationoftheimageyouseethroughboththenderscope
andeyepieceofthistelescopeisnormal.Thisallowsyoutousethis
telescope effectively when viewing terrestrial as well as astronomical
objects.
Therearemanyconditionsthatmayaffectyourabilitytofocusorobserve
celestialobjectsclearly.
• Brightlylitareas(lightpollution)willmakeitdifculttoseefaint
objectsinthesky.Itwillalsomakeitdifcultforyoureyestoadjust
tothedark.Youshouldtryandndadarkareaandallowyoureyes
toadjusttothedarkbeforemakingobservations.Usingaredltered
ashlighttoviewchartsandyourtelescopecomponentsisrecom-
mendedtopreserveyournightsight.Thebestviewingconditions
are when the sky is inky black.
• Hazyskies,pollution,cloudsandmoisturecanallaffecttheclarityof
your viewing image.
• Avoidtouchingtheeyepieceoropticaltubewhilelookingthrough
thetelescope.Thevibrationscausedbythiscontactwillcausethe
objectyouarelookingattomove.Youshouldalsomakesurethat
thesurfaceyouplaceyourtelescopeondoesnotvibrateormoveas
thiswillalsocauseyourviewingobjecttomove.
• Youshouldavoidsettingupyourtelescopeinsidearoomlooking
throughanopenwindow.Thedifferenceinairtemperaturesmay
result in a blurry image.
• Viewingthroughaclosedwindowmightalsoresultinadistortedim-
ageduetothevaryingdensitiesofwindowglass.
• Avoidviewingobjectsthatarelowonthehorizon.Objectsthatare
higher up in the sky will appear much sharper.
• Suddenchangesintemperaturemaycausecondensationtoappear
on the optical components of the telescope. It is best to set up your
telescopeaheadoftimeandthenwaitwhilethetelescopeadjuststo
the new temperature before using it.
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