Safe Eclipse Observing Prof. Patricia Reiff, Rice University Some of my favorite safe ways to observe the Eclipse (or the sun, any time). These are generally listed in order of expense, cheapest first. 1. Safely First! For important safety information, please check the NASA Eclipse site: https://eclipse2017.nasa.gov Here is the link to the safety flyer (please print out and distribute): https://eclipse2017.nasa.gov/sites/default/files/publication s/Safety_508.pdf 2. Pinhole projection. A. Get a cardboard box. Punch a hole into one of the ends (I use one of the smaller ends to make a longer path so a bigger image). Since the cardboard may have ragged edges from the punched hole, I generally just make the cardboard hole larger and then cover it up with a piece of thick paper and punch a smaller hole in it. Put a sheet of white paper into the opposite end. You may need to tilt the box, propping it up, to see the image. B. For a brighter image, if you just make the pinhole larger, it will get fuzzy. Instead, make a larger hole but use a pair of inexpensive reading glasses to focus the image inside the box. The image still won’t be very large, but it will be brighter and in better focus. You may need to adjust the placement of the box (the best strength of the reader depends on the length of the box: 2 or 2.5 magnification works well with a 14-16 inch box). C. This shows the image inside the box. D. My favorite way to do a pinhole is to take a piece of STIFF cardboard and punch holes in it, describing the date and location. Then take a photo of its SHADOW. Each hole makes a crescent eclipse! Get it ready the night before (a fun kid’s activity), and then photograph just after totality.
Some ofmy favorite safeways to observe the Eclipse (or the sun, any time). These aregenerallylistedinorderofexpense,cheapestfirst.1.SafelyFirst!For important safety information, please check the NASAEclipsesite:https://eclipse2017.nasa.govHere is the link to the safety flyer (please print out anddistribute):https://eclipse2017.nasa.gov/sites/default/files/publications/Safety_508.pdf2.Pinholeprojection.A.Getacardboardbox.Punchaholeintooneoftheends(Iuseoneofthesmallerendstomakealongerpathsoabiggerimage).Sincethecardboardmayhaveraggededgesfromthepunched hole, I generally just make the cardboard holelarger and then cover it upwith apieceof thickpaper andpunchasmallerholeinit.Putasheetofwhitepaperintotheoppositeend.Youmayneedtotiltthebox,proppingitup,toseetheimage.B.Forabrighterimage,ifyoujustmakethepinholelarger,itwill get fuzzy. Instead,make a largerholebutuse apair ofinexpensive reading glasses to focus the image inside thebox.Theimagestillwon’tbeverylarge,butitwillbebrighterandinbetterfocus.Youmayneedtoadjusttheplacementofthe box (the best strength of the reader depends on thelengthofthebox:2or2.5magnificationworkswellwitha14-16inchbox).C.Thisshowstheimageinsidethebox.D.MyfavoritewaytodoapinholeistotakeapieceofSTIFFcardboard and punch holes in it, describing the date andlocation.ThentakeaphotoofitsSHADOW.Eachholemakesacrescenteclipse!Get it ready thenightbefore (a funkid’sactivity),andthenphotographjustaftertotality.
3.EclipseGlasses:A.Eclipseglassesareasafeandinexpensivewaytoobservethe eclipse. Be sure you get them from a reputable source,that have the “CE” or “ISO” certificationmarked on them. Ilike the ones from Rainbow Symphony since they give apleasing orange colored sun. You can use them to observesunspotsatanytime!Protectthemfromscratchesorholes.B. Although eclipse glasses are easy and fun, they do notmagnifythesun.Youcantell theprogressionof theeclipse,butyougenerallywon’tbeable toseeanysunspots,unlesstheyareextralarge.4.SolarFiltersA.Forme, themostcomfortableandnaturalviewofa totaleclipse(solarorlunar)isfromapairofbinocularsmountedonatripod.Youcanusetheshadowofthebinocularstodoarough alignment (minimizing the size of the shadow), thenlookthroughtheFILTEREDbinocularstofindthesun.Zoomouttofindthesun,thenzoomintogetabetterview.Haveastepstoolonhandsochildrencantakeapeektoo.Byputtingonthetripod,severalpeoplecansharetheviewwithouteachhavingto“find”thesun(noteasyusingfilteredbinoculars!).Iprefera10-22zoom,50mmdiameterbinoculars…goodqualitybutnottooexpensive.(Youcangetcheaponesfor$30butIpreferthegoodonesfor$150).SolarND(neutraldensity)filtersarealsoavailableforlargertelescopes.AlwaysputthefilterontheOBJECTIVEendofthetelescope,neverontheeyepiece.B. There are two critical pieces of equipment: The solarfilters ($20each) that cap thebinoculars (I like theonesatRainbowSymphonysoIcanslipthemonandoffeasily)https://www.rainbowsymphonystore.com/collections/solar-filtersMeasure the OUTSIDE diameter of your binoculars,telescope,videocamera,orcameralens,andgetthenextLARGERsize.Theyprovidefoamtapeforasnugfit…youdon’twantthemtofalloff,butyoudowantthemtocomeoffeasilywhentotalityhits!The second critical item is the “Binocular tripod adapter” - purchase from a photo ortelescope store or from Amazon. Prices range from $9 to $28. One end screws into themountingholeonthehingeofyourbinoculars(whichmightbecoveredbyacap).Mounttheflatendontoyourphotographictripod.Thisgivesyoufullcontrolofthedirectionthatthebinocularsarepointing.Thisisreallygoodforobservingthesun(orotherastronomicalobjects-youonlyneedthesolarfiltersforobservingthesun).However,iftheSunisveryhighinthesky,itbecomesawkwardtolookthroughbinocularsonatripod-seebinocularprojectionbelow.
C.Finding thesun in filteredbinoculars isharder thanyoumight think - the only thing you can see is the sun! Don’t“sneakapeek”-itcankillyourvision!TofindtheMOONinthe sky, or a bird in a tree,with binoculars, first look at itdirectly with your eyes straight ahead (moving your headtill you are facing it squarely). THEN put the binoculars(zoomedOUTforminimummagnification)uptoyourfaceandtheobjectshouldbein(ornear) the fieldofview.Thenzoom in.Theprocedure to find theSUN is similarBUTyouhave todo itwithyourEYESCLOSED.Closeyoureyesandmoveyourheadarounduntilyoufeelthesun’sheatonyourfaceandyouthinkyouarefacingstraightatit.Thenbringup theFILTEREDbinoculars (zoomedOUT)andopenyoureyes.Again it shouldbe inornearyourfieldofview.D.Ifyoucan’tfindthesun,oftenafriendcanseetheshadowofthebinocularsonyourfaceandtellyoutotipback,orleft,orwhatever.HereIamlookingattheSunnearlocalnooninMay,neartheelevationoftheeclipseinJanuary.Igotagoodview but it is really tough on your neck to hold it for verylong.5.BinocularprojectionA.Whenthesunishighinthesky,themostcomfortableviewis using a pair of binoculars to project an image. Put thebinoculars on a photographic tripod, using a “binoculartripod adapter” - see 4B above. Cover one lens of thebinocular with its cap or with a solar filter but leave theother lens uncovered. NEVER LOOK AT THE SUNTHROUGH BINOCULARS WITHOUT THE SOLAR FILTER ON! NEVER LEAVE THISSETUPUNATTENDED-SOMEONEMIGHTTRYTOLOOKTHROUGHTHEBINOCULARS!IputthetripodonitsLOWEST(shortest)settingtomakeithardforsomeonetotrytolookthroughthebinoculars-thatalsomakestheimagethebrightest.Adjustthetipandrotationofthetripodheadtomaketheshadowofthebinocularsthesmallestpossible…thenitwillbelookingexactlyatthesun.Ideally,adjustthelookdirectionslightlytoprojecttheimageintoashadowedarea,ifoneishandy(seephoto).Putapieceofheavywhitecardboardtoprojecttheimageonto,ortapeawhitepieceofpaperontosomethingheavy.Tipthepapersoitisperpendiculartothelineofsight,sothatthesun’simageisacircle,notanoval.Usethe zoom and focus adjustments on the binoculars to make the best view. For a largediameterbinoculars,youcangetanimage3inchesacrossormore.B.Ifyoudon’thaveashadedareanearby,youcanmakeyourown shade. Here are some smaller binoculars on a smalltripod.Againuse theshadowof thebinocs toalign.See theimage of the Sun on the paper near the shadow of thebinoculars.
C.Wrapadarksheetortowelaroundthebinoculars,keepingonly theuncoveredaperture in the sunlight.The towelwillmakeashadowthatyoucankeeptheimagein.Astheearthrotates,youwillneedtoadjustthepointingofthebinocularstokeeptheimageintheshadow.6.SunspottersA.Thesafestwaytogetabig imageof thesun is throughacommercial“Sunspotter®”devicefromScienceFirst.It’snotcheap(around$400),butit iswelldesignedandcanbeuseto sketch sunspots at any time(http://shop.sciencefirst.com/starlab/models/5818-sunspotter.html). To align, first move the device around(sliding the triangular assembly up and down and rotatingthewholethingsothattheshadowofthepeg-abovethe“p”in “Sunspotter” - is minimized.) Then a white dot shouldappear near the white circle (lower right). If the device isaligned, putting thewhitedot into thewhite circle should give youa solar imageon thewhitepaper.Mine is a littleoffbut it is closeenough to find the sun.Youcanadjust thefocusifnecessarybutmineisusuallyjustfine.B. The Sunspotter evenworkswith the sun nearly directlyoverhead.Anotheradvantageofusingasunspotter is thatayoung person or student can be in charge of keeping italigned…thereisnowaytolookatthesundirectlythroughit.7.H-alphaTelescopeThe most expensive way to observe the sun is through aHydrogenAlpha telescope. Insteadof filteringout all of thedifferent wavelengths of light equally, it selectively admitsonlytheredlight(656nm)whichisemittedbyaHydrogenatomnearthevisiblesurfaceofthesun.YoucanobservetheSun’s prominences, convection cells, and plages any time -notjustduringaneclipse.Byslightlyadjustingthewavelength,youcanadjusttheheightofthe features that are best seen. Less expensive models use photographic tripods. Moreexpensivemodelshavemotorsfortrackingthesunacrossthesky.Iowna40mmCoronadoandIfinditcanbetrickytokeepthesuninthefieldofviewwithoutthetrackingmotor.Note: All imagestakenbyPatriciaReiff([email protected]).Permissionisgrantedtoprintoutanddistributethisfornon-commercialeducationaluse.Disclaimer:Ihavenocommercialinterestinanyoftheseproducts(Ihavepurchased theseproductspersonallyandamahappycustomer);however Ido sell eclipseglasses throughmycompany’sonlinestorehttp://spaceupdate.com/store/equipment.html
