UMBRETLA?

BY BILL NORMAN

noPman A Brandof PromarkIntemational, Inc.

1268Humbracht Circle . Bartlett,lL 60103 1-800-787-8078. 630-233- 1538 [email protected]. www.NormanLight.com WHY UMBRELLA?

by Bill Norman

ovER250,000 coPtEs IN PRINT

@ Copyright1970 - Norman Enterprises,Inc. WHY UMBRELLA? In recentyears, umbrella bounce lighting has becomeincreasingly oopriutin almostevery phase of electronicflash photography Although no'particularlighting technique will solveall yourlighting problems' um6rellaoouncE tigtit has true meritswhich you mayfind very useful' The purposeoithis reportis to familiarizeyou with answersto the ouestionsmost often askedus concerningumbrella bounce lighting' Wehooe vou will findthis information valuable for yourparticular type of eIectronic flash PhotograPhY. Yourquestions and-suggestions are alwaysappreciated at Norman Enterprises,for they enableus to improveour productsand to meet yourcontinua lly cha nging needs.

WHAT ARESOME OF THEADVANTAGES OF UMBREIIA BOUNCEIIGHTING OVER DIRECT TIGHTING Umbrellabounce light is a softerlight than mostdirect light This soft effectcan be creatld in waysother than umbrellabounce, but in most casesthe other methodsare not as portableor as practicalas umbrellas.For example, many soft light lampheads or bounceflats are too largeto useon location;also, wall and ceiling color encountered on locationare not always correct for bouncinglight. Thissoft lightis generallydesirable for highkey photography where shadowareas aie keptto a minimum. Muchof today'slow key portrait photographyis done with umbrella bounce light because light Placement is uncomplicatedand skin tones are quite flattering. Umbiellabounce light produces a larger,more even angle of cover- agethan most direct light units. This can mean that light placement is lels critical,especially in situationssuch as fashion and some commer- cial photographywhere your subject is movingover a given.area. UmUrettibounce light tends to wraparound the subjectand in manyinstances, this reducesthe numberof Iightsrequired to createa particulareffect. Also,umbrellas can be utilizedto simulatethe "north-

_l_ o 2..'- l- I UMBRTTI.AB0uilctI.IOHTITTII|S T|) IVRAPAR()UND THE SUBJECT. Fig.1 light" effectand therebyminimize retouching. In smallshooting areas where you are not ableto movedirect light equipmentback far enoughto obtainadequate depth of light,umbrella bouncelight is especiallyhandy. lvlaximumdepth of light penetration is possiblebecause the light fall-off(inverse square law) is measured from the light to the umbrella,then back to the subject.

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WHATARE SOME OF THEDISADVANTAGES OT UMBRELLA BOUNCETIGHTING OVER DIRECT IIGHTING? In situationswhere depth of field is to be maintained,umbrella bouncelighting generally requires more light output from yourelec- tronicflash unit thanyou needwhen using direct light. This is due to the lightlosses in the umbrellafabric as wellto the increasedangle of coverageobtained from bouncing the light. In manycases this means that the electronicflash equipment you needwill costmore because of the additionalpower required to work at a givenf stop. However, sinceyou may not requireas manylampheads to createa particular effect,your overall investment in equipmentmay be similarfor a direct orumbrella bou nce system. Umbrellalight is notpractical for manysituations where a highde- greeof contrastand control is needed.This would be the casewhen usingbarn doors, snoots, spot lights,etc. However,in manyof these instances,umbrella lighting may still be utilizedas a fill lightsource. Umbrellalighting does not lenditself to situationssuch as outdoor shootingon windydays, or to candidwork where you haveneither time nor spaceto set up a Iightstand and umbrellaassembly. In somecases modeling lights are not brighi enoughfor use in umbrellasand it is difficultto composelighting and focus the camera. This problemhas beensolved in manyinstances by the use of high poweredquartz modeling lamps.

CHOOSINGTHE PROPER UMBRETI.A Thereare round umbrellas, square umbrellas, white umbrellas, silver umbrellas,large umbrellas, small umbrellas,umbrellas designed to changecolor balance, and everycombination imaginable. We haveno stockanswer designed to recommendwhich one you need,but rather feelan intelligentdecision should take into consideration the equipment youwill be usingand the effectyou desirein yourphotography.

WHAT ABOUTROUND UMBREIIAs? Roundumbrellas produce round catch lights. ln most casesthe catch light lookscompletely normal. lt is sometimespossible to see the actualshape of the umbrellaperimeter in the catchlight. This couldbe desirableor undesirable.lt's all a matterof personalprefer-

Roundumbrellas generally have curved ribs. Theangle of reflection is lessnear the edgesof the curvedribs than it wouldbe nearthe edges of flat ribs,thus you get a greaterwrap aroundeffect than with flat ribbedumbrellas. This addedwrap around effect is verydesirable for colorportraiture. The resultingsoft light requireslittle or no fill light, dependingon the desiredeffect. The curvedribs also enableyou to featherthe light with more controlthan viith flat ribbed umbrellas, becausethe angleof coveragehas a moredefined cut off point.

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tig. 4 cuRvtontBs ww TflEu0Hr MOUilDTHt SUBJECI In someround umbrellas, the curvedribs can causethe reflected light to producea focal point. This focal point couldbe undesirable whenusing the umbrellaat a distancefrom the subjectequal to the focallength of the umbrella-lightcombination. Testing your umbrella to makesure this is nota problemwill enable you to utilizethe umbrella to yourbest advantage. The umbrella focal point is morenoticeable in silverumbrellas with non-textured fabrics because this type fabric pro- ducesa harsherlight. Harshnessdepends both on the fabrictexture andthe reflectionquality of the material.lt varieswith each umbrella rype.

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tig. 5 CURVEI)RIBS CAN CAUST A TOCAI. POINT

HOW AEOUT SQUAREUMBRETI.AS? Squareumbrellas produce square catch lights. Some photographers likesquare catch lights because it lookslike the reflectionfrom window light. On the other hand,some photographersobject to squarecatch lights. lt's strictlyup to your personalpreference. Squareumbrellas generally have flat ribs. Sincethe angle of re- flectionis equalto the angleof, incidence, the light paiternproduced by a fully openedflat ribbedumbrella has no apparentfocal point,and thus produces a more even angle of coveragethan curved ribbed umbrellas.

Fig.6 fig. i FUTTY()PTNE|) UMBRITI.A ct0st0 0oviltuMEREl-ta wrl)tRANGII 0t covtRAct TTSSC(}VERAGE SOFTTRTIGHI l)UTPUT M()N[TIGHI OUTPUT Manysquare umbrellas can be openedto variousdegrees, permit- ting the reflectedangle of coverageand the lightoutput to be controlled -4- at a givendistance. Opening the umbrellawidens the angleof coverage and lowersthe Iight output. Closingdown the umbrellanarrows the angleof coverage,jncreases the lightoutput, and producesa moreharsh effect.

WHAT ABOUT WHITE UMBRETIAS? Whiteumbrellas produce a softerlight than do silverumbrellas of compara ble size. We havefound the light losswith most white umbrellasto be ap- proximately2f stopsless than direct light. Thesefigures are basedon white umbrellaspowered by an averagestudio lamphead containing an averagereflector. Our definitionof an averagereflector is one producing a 10to 1 lightoutput ratio and havingan includedangle of 60' coverage. This10 to 1 ratiosimply means that the reflectorproduces 3f stopsmore light than the same lampheadwould on bare bulb operation. Many white umbrellasutilize translucent fabrics. Thus some of the lightwill filtef throughthe umbrellaas well as reflectfrom it. This can be an advantageif the umbrellais placeddirectly in front of a bounceflat, wall or corner:the additibnallight reflected from the bounce flai, wall or cornermay producean even softer lightingquality. The translucentfabric can also be a disadvantagein situationswhere the camerais locatedbehind the umbrella:filtered light could strike the cameralens and causeflare. With umbrellalighting it is desirableto use a lensshade to preventflare

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fig. I ]NA STUCTIIIFABRIC ADDITIt|T{ALI.IOHT RTFTTCTID FITTTRTOI.IGHI MAY CAUST TIART. fRoMtvA - A|DSS0FT UCHflN00UAUTY. HOW ABOUT SITVERUMBREIIAS? Silverumbrellas produce a harsherlight than do white umbrellas of comparablesize. This harshlight is still much softerthan the light producedin most direct light systems. Silverumbrellas reflect more light than white umbrellas,making them desirablewhere maximum depthof field is requiredfrom a bouncelight system. Our tests show that silver umbrellasIose from r/zto IVzf stopsover direct light, depend- ing on the reflectionindex of the Darticularsilver nraterialand the shape of the umbrella. Again, these figures are based on an average studio lampheadcontaining an averagereflector. Somesquare silver umbrellas have a reversiblefabric which has a high contrast design on one side and a lower contrast desisn on the otherside. This enablesyou to vary contrastby reversingthe fabric. In all the silver umbrellastested, we found that very litfle light was transmittedthrough the umbrella. This minimizedthe problemof flare due to light filteringthrough the umbrella. However,one must be awarethat lighttraveling around the edgeof the umbrellacould cause a problemto yourcamera iens.

WHICHTO UsE.TARGE OR SMAtt?

Largeumbrellas produce a softer,broader light than do smaller umbrellas.The largersize will illuminatethe subjectfrom greater angles. lf youwere to createthis effectwith directlight you coulduse severallampheads (fig. 10). Onedisadvantage of usingmultiple lamp- headsis that crossshadows will be produced. To-eliminarecross shadows,a diffusionsheet of sufficientdensity would have to be placed in.frontof the lampheads(fig. 11), making them appear as onesingle lightsource.

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Fig.l0 tig.l1 MUI.TIPTEI,AMPHTADS PNODUCE 0ltFusroflsHttT H.tM ATIS cR0sssilAD0ws. cnosssHADows

Figures12, 13,and 14 further illustratehow the size of the light source effects softness. In figure 12 the Iampheadis pointed direcfly at the subject. The anglesof reflectjonare greatat the sidesof our subject,thus the illuminatingpower of the light sourceis weak at the sidesof the subject. The illuminatingpower of the lampheadis great only at the front surfaceof our subject where the subject plane is per- pendicuIar to the lightbeam. br!. A.!1. ol R.ll..lion

fig.12 DIRECTLlcllT - ltLuMltlATlt{GPolvtR ls wtAl(AT THt Slots 0f rHt suBJEcT.

Figure 13 showsthe lampheadpointed into a sma.llumbrella The angle of reflectionis less at the sides of the trapezoidalsubject than wii-htne direct light: thus greaterillumination on the sides of our subjectis obtainedthan with direct light.

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Fis.13

SMAII.UMBRTTI-A: II.LUMITIATIS THI SIDTSt}F THt SUBIECIEETTER IHAII DIRTCT TIGIIT'

Figure-of 14 showsa lampheadpointed into a largeumbrella The angle reflectionis evenless than that obtainedwith the smallum- brella,thus a softer,more even light is produced.

Fis.14 UMEREIIA'IITUMII{ATES SII)IS OF SUB.|ICI BETTTR IHAN SMATI. UMBNIIU. In caseswhere depth of field must be maintained,it takesmore light outputfrom your electronicflash to illuminatea largeumbrella thanto illuminatea smallurnbrella. This is becausethe lamphead mustbe furtheraway from the umbrellain orderto illuminatethe en- tirefabric.

\\ tis.15 fig. | 6 LtMPlt0 BAC|(tR0M UMBnELU tAl,tpHtAoCtostR T0 uMBnt[u sofl UGHT,M0nE CoVtnAGt M0REt-loHT tNTtt{StTy, ttss c0vt[A8t HOW ABOUTSMAII UMBRETTAS? Smallumbrellas produce a harshlight compared to largeumbrellas. lf an umbrellais too small in relationshiDto the diameterof the lampheadreflector, a goodportion of the light will bounie back into the lampheadreflector and producea void in the beampath: you will noticeboth a lightoutput loss and a blackshadow in the centerof the catch light.

tig. It uMBn[[[AT00 sflat-t [{ Rtt-Altoill0 tAMpH$DpRoDtJcES A V0t0 n THt EIAMpATfl. WHEREDO YOU GO FRO'\AHERE? Usingthese basic principles as a guide,you can moreintelligenfly selectthe bestumbrellas for yourparticular type of photography. Maywe suggestthat too much of a goodthing can be badl For example- whenusing two or moreumbrellas, it is possibleto make the lighttoo softor too flat. lf this happens,your photograph will lack depthand the colorscan be too bland. Don'tforget that you are gen- erallytrying to makea two dimensionalpiece of photographicpaper lookthree dimensional.