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FLASH METER IVUSER GUIDE

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Incident and Reflected Light Meterings

I ncident I ight metering: characteristics

Incident l ight metering: basic operation

Determining the l ight ing rat io.

Flash Meter IV analyze function

Aperture-priority meteri ng

Exposure meters and fi lm sensitivity

Reflected light metering: characteristics

Reflected light metering: basic operation

Subject contrast and exposure determination.

Contrast control

Creative exposure measurement .

Cum ulative exposure metering

B o o s t e r I I . . . .

Spot-probe attachment . .

Booster compensation .

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Whether working under continuous light sources such as sunlight or tungsten bulbs,or with instantanieous light sources such as electronic flash, photography is a process

in which illumination from the light source strikes and is reflected off the subject,passes through the camera lens and forms an image on a light-sensitive surface. Amechanism for controlling the lens aperture and shutter speed, as well as flash outputwhen using flash light, is required to make sure the right amount, of light reaches thefilm olane.

There are two basic ways of measuring this brightness: incident light meteringsystems which indicate the required exposure by measuring the amount of light(llumination) illuminating the subject, and reflected light metering systems whichindicate exposure by measuring the amount of light reflected off the subject(luminance) and received by the camera (See Fig. 1).'

The Minil1a Flash Meter IV permits incident light metering with spherical diffusers,mini receotors or flat diffusers, or reflected light metering with Viewfinder 5o or View-finder 10d II, a reflected light attachment (40' acceptance angle) or the Minolta Booster II.

Selecting which metering system should be used cannot be reduced to simple Suidg- ,lines based on specific photographic situations or whether the receptor is directed at r

the subject or the camera. Rather, the selection should be based on a thorough under-standing of the differences between the merits of the two systems.

To ddmonstrate the differences between incident and reflected light meteringsystems, we photographed black, gray, and white wallpaper samples (respectivereflection faciors [ii., the ratio of reflected light to incident light on the sublect] ofapprox. 4o/0,180/i and90%) shown on page 3 under the same light conditions andmetereO with the Flash Meter IV. The pictures in group A were exposed as indicatedwith incident light metering; those in group B were exposed as indicaled with reflectedlight metering.

Fig. 1 Incident light metering Reflected light metering

lncident l iqht Light source

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l-ll Grl mllncident light metering Camera(using spherical recePtor)

Reflected light metering

Reflected l ight metering(ref lected light attachment)

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Incident light meteringInincident l ight metering, l ight i l luminating the subject (i l lumination) is measured andexposure is calculated with the formula [i l lumination (l ight striking the subject)x

Accordingly, incident light metering will indicate the same exposure level (f/16 ingroup A photographs)for all subjects, i.e. irrespective of the subject reflection factor,when photographing uMer the same light conditions, and therefore render the neutralgray sheer as gray, the high reflection factor white sheet as white, and the low reflectionfactor black sheet as black.*Standard reference subjects may have a ref lection factor anywhere between 120/o and26% Minolta bases its readinos on a

reference subject with an 180/o reflection factor.

Spherical diffuser

Flat diffuser

Minireceptor

Reflected light meteri ngReflected light metering measures the light reflected by the subject luminance andcalculates the exposure so the specific subject luminance is rendered in neutraltones. The formula used in this calculation is: fsubject luminance (i l lumination)xsubject reflection factor + film sensitivity : exposufe.]

Accordingly, reflected light meters will indicate different exposures (f/5.62, f/160, andfl32stor the black, gray, and white sheets, respectively; see group B) for subjects withdifferent reflection factors when photographed under the same light conditions. Theresult is that black, gray and white subjects will all be rendered in the same neutral gray.

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Ref lected-l ight attachment

Viewfinder 5o

Booster II

The most outdoor scenes have a reflection factcir close to 1B%, the reflection factor ofthe reference subject on which most incident light meter readings are based. Thismakes the incident light meter quite effective for portraiture, and is the reason incidentlight meters are most frequently used for this and similar applications.

In addition, most photographic situations include objects with reflection factors bothhigher and lower than the 180/o reterence. As previously explained, incident lightmeters will reproduce these subjects in respectively lighter and darker tones. Theincident light meter is therefore suited to situations requiring exposure averagedacross the scene, as well as to shots of open scenery, everyday street scenes andmost indoor photography.

Another reason why incident light meters are so frequently used is that the lightreceptor accepts and exposure calculations are based on the full range of light strikingthe subject. In most situations the surface of any three-dimensional subject is coveredby both light and dark areas (shadows). What's more, some amount oT light from alllight sources, including the sides and back of the subject, is reflected towards thecamera and has some effect on the picture. (See Fig. 2-a.)Spherical receptors areable to reproduce and measure the same illumination as that striking the subject for amore precise exposure determination.

Conversely, with flat subjects such as pictures and posters, less light originatingfrom the sides or back of the subject is reflected to the camera, and has a correspon-dingly smaller effect on the exposure. (See Fig. 2-b.) In these situations, the flat diffusef-ris used to more nearly reproduce the illumination on the subject for exposuredetermination.

@ Three-dimensional subject @ Flat sublect

ryry

Fig. 2 Effect of illuminationsources InphotograPhY of three-dimensional and flatsubjects

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Incident light metering: Basicoperation

Minolta Flash Meter IV operation in the incident light meter mode is shown below.

t ' ' :" i ' " t Attach thei,, .N,'.. ,i spherical diffuseror flat diffuser to thereceptor, or use the minireceolor.

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- I Set rhe mode

s, I selector to theoeisiirio meter type.(AMB|, CORD, NON. C.)

i ";;i;" i Set the functioni .fi '^"r selector to TIMEor FNo. TIME: shutterpriority meteringFNo. : aperture-PrioritYmetering

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Use the. *F i decrease/inCiease control to selecleither the shutter speedor aperture (f-number).(fhis should normally beset to the flash syncspeed during flashphotography.)

o AMBI: measures ambient (continuous) light.CORD, NONC: measures flash light or flash liglt and ambient light.

o Please read the Flash Meter IV instruction manual for details on operation.

meter to produce a more accurate reading.As stated before, incident light meters make exposure calculations based on the

exposure required to reproduce a neutral density subject with a reflection factor of1B%. Special consideration is therefore required when metering and photographingsubjects with a significantly higher of lower reflection factor than this 1B% standard.

: Hold the: Flash Meter IV

near the subject withthe receptor pointingdirectly at the camera

Press the' " , meaSuring

button to take ameasuremenl.

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(A) Exposed at metered values. (B)Slightly "underexposed"

lf the reflection factor is high: lighter subjectsFor example, if the scene is of predominantly white, i.e. has a high reflection factor, and these white subjects are tobe reproduced with maximum detail, better results will be obtained by underexposing the picture one-half to onestop from the exposure indicated by the incident light meter.

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Exposure: (A) 1122, 1/60 sec.; 1/3 stop(B) t132, 1/60 sec; 1/3 stop

lf the reflection factor is low: dark subectsSimilarly, if the scene is dark overall, i.e. has a low reflection factor, and the dark areas are to be emphasized, theexposure should be increased one-half to one stop from the exposure indicated by the incident light metering.

Note that the exposure compensation described here and above should not be used when photographingpeople and other subjects having an average reflection factor.

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Exposure: (A) 11132, 1/60 sec.; 1/2 stop(B)t122,1/60 sec.; 1/2 stop

(B) Slightly "underexposed"

(A) Exposed at metered values.

lf the subject is backlitNormally, opaque subjebts illuminated by backlightingor side lighting can be safely metered by followingstandard incident light metering rules, but there are alsotimes when the subject is translucent and/or i l luminatedby backlighting and the receptor must be directed atthe light source itself in order to meter and determinethe proper exposure.

In such situations light from all sources will have adrrect effect on the exposure, and it is necessary topoint the receptor in numerous directions in order toproperly meter the overall light situation.

In such situations, a standard reading should betaken with incident light metering, and the receptorshould be pointed bothup, away from the lightsource, and directly at thesource. The exposuremust then be determinedwith resoect to thecomposition, desired Exposure: Il32+112,1/60 sec; 1/3 stopresults and other lightingfactors.

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Open sceneryAlthough the light receptor is normally placed near thesubject and directed at the camera lens, this is oftennot possible and frequently not necessary when photo-graphing outdoors. The receptor can usually be placednear the camera with acceptable results. This isbecause a light source such as the sun will provide thesame illumination at the camera as at the subiect.

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Determining the lighting ratio

The lighting ratio, or contrast, is the ratio between thehighlight and shadow areas of a subject. In normalcolor photography, a lighting ratio of between 4: 1 and8:1, or two to three stops, will produce the most naturalrendition of colors and contrast.

The lighting ratio can be used to control the overalllighting effect, including the relationshtp between themain subject and background or the effect of shadowson the main subject during portrait or product photo-graphy in a studio environment.

The Minolta Flash Meter IV can meter illumination ofthe subject from a number of individual light sourcesusing a flat diffuser and store readings in the memoryfor easy comparison on the exposure index number(ExlN.) display and contrast scale to determine thelighting ratio.

To illustrate how the lighting ratio can be determined,refer to the photographs on the page at right. This shotwas illumrnated with two lights: the main light sourceand a fill light. The lighting ratio was determined asfollows:(1) Attach a flat diffuser to the light receptor.(2)Set the film speed and metering mode as described

in "Basic operation" on Page 9.. Make sure the function selector is set to TIME(3) Foint the flat diffuser directly at the main light source

from the subject position and store the reading in thememory.

(4) Now meter the fill light in the same way and storethe reading.

. The flat diffuser should be shielded that noillumination from the main light source directly strikesthe flat diffuser.

(5)The difference between these two readings can beread from the contrast scale (or the f-number scale).Stored values can also be recalled to obtain thedifference. This difference is the ratio of the two lightsources on the subject. (See Table 1 and Fig. 3.)

For example, if the exposure index number Jor the mainlight source is 1O.2 (11322) and that of the fill light is t122,the difference in sources is 10.2- 9.2:1.O stop, or alighting ratio of the main light to the fi l l l ight oI2:1.*The lighting ratio is normally determined in order to check theactual lighting situation when photographing subjects wlth anormal reflection ratio. Extreme dlfferences in the reflectionratio of the subjects composing the picture may exceed thelatitude of the film even after the llghting is adjusted. In suchsituations the techniques used Jor determining exposurebased on subject contrast as described on page 22underreflected light metering should be used.

Meter the main l ight(memorized)

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(A) Lighting ratio: B:1Exposure: (A) Il22 + 213, 1 160

sec; 1/2 stop

These two exposureswere made with differentlighting ratios to demon-strate the effect of differingratios on the final expo-sure. The top photographhad a lighting ratio of 8: 1which was adjusted to the2:1 ralio o1 the lowerphotograph by fi l l ing insnadows.

Fig. 3 Lighting ratio

(B) Llghting ratio'. 2:1Exposure: (A) Il22 + 213, 1 160

sec; 1/2 stop

Table 1

Difference inmetered exposure(Ex lN )

Lightingratio

1 stop 2 : 12 stops 1 1

3 stops B : 1

4 stops 1 6 : 1

5 stops J Z . I

6 stops 64:1

7 stops 128:1

Flash Meter lV analyze function

ln actual flash photography the total light used for the exposure contains some degreeof ambient light-unless you're working in total darkness. This means conventionalflash meters (e.9. the Minolta Flash Meter III) express the required exposure as thesum of both constant and flash illumination striking the receptor within the period theshutter is open. Accordingly, the photographer does not know the amount ofillumination provided by only the flash or ambient light, and the meter seems toindicate a constant exposure even ijthe shutter speed was changed after lightmetering was completed.

The Flash Meter IV employs separate metering and adjustment for ambient andflash exposures. lt then stores these values to calculate the exposure setting.Accordingly, the ratio between flash and ambient light can be read from an analogscale on the Flash Meter IV and used to retain the effects o{ ambient light (whethernatural light or modeling lights) or to emphasize shadows, Furthermore, this ralio canbe controlled by changing the shutter speed to vary the amount of the ambient light orthe guide value can be adjusted to vary the amount of flash light after metering iscompleted.

When metering the scene shown in the photographs at right with the Flash Meter IV,set the normallanalyze switch at ANALYZE lo meter the flash light; the three pointersappear on the analog scale and the exposure required for the overall light level is shownon the digital display. The pointers in pholographB indicate:(1) Total exposure value of the ambient light and

electronic flash light (the pointer at 0 on the. contrast scale)

(2)Proportion of the flash light (blinking pointer)(3) Proportion of ambient light

The difference between flash and ambient light levels can be determined withpointers (2) and (3). The difference here is approximately 1/4 stop, indicating nearlyequal portions of flash and ambient light in the exposure (see photograph B at right). pIn photograph A, the shutter speed was lowered lo increase the tungsten (ambient)light component, As shown on the contrast scale, the ratio of flash to tungsten light isclear: the flash light to total light ratio is indicated at 2 stops while tungsten light isindicated at 1/4 stops.

In photograph C the situation was reversed: the flash units power level was increasedto increase the amount oJ flash light in the exposure. The tungsten light to total lightratio is - 2.5 stops, making the flash the main light source. flffhile the same ratio canbe obtained by increasing the shutter speed, the total light level will also changq andthe display will indicate a larger aperture is required.)

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Apertu re- priority flash meteringThe Flash Meter IV permits aperture-priority flash metering in addition to ambient lightmetering of daylight and tungsten light. i ;:1 , .r . , : .,Since ambient light exposures are controlled by the aperture, which Controls the .,,.,amount of light striking the film, and shutter speed, which controls the length of time'rthis light strikes the film, one must determine the aperture for shutter-priority meteringand, conversely, the shutter speed for aperture-priority metering.

However, tne flasn unit's duration is very short, and with most cameras, it is not , .:possible to control the amount of time lighifrom the flash strikes the film plane. i)''Accordingly, the aperture is normally adjusted to control the amount of light reachingthb film. (On automatic flashes the flash duration is controlled.) ln conventionalmetering systems (the Minolta Flash Meter III), the shutter speed was set (within thecamera's X-sync range)and the aperture was calculated for the amount of flash andambient light which would strike the receptor at this shutter speed.

Since the Flash Meter IV employs separate metering and adjustment for ambientand flash exposure which can indicate the amount of flash light, the scene can bemetered with the required X-sync shutter speed and desired aperture, and the meterwill indicate how much additional flash light (expressed as a 'guide value" IGW isrequired for the exposure. This figure is based on a constant (unvarying)ambient lightlevel, and indicates how many stops the power level must be increased or decreasedto provide a proper exposure at the specified aperture.

For example, less d'epth of field was desired in the photograph at right. Accordingly,the aperture was set to f/16, and the meter indicated * 1 GV indicating that flashillumination must be reduced one stop, i.e. power should be reduced lo 1t2 the currentlevel. Similarty, if +'1 GV is indicated, the power level should be increased one stop.

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&posihte mefers'ehd film SiensitivityIt is important to know the characteristics of the film when thinking about exposure.When the film is developed, the amount of light (exposure)* on the film appears as thedensity of images on the film. The line graph illustrating the relationship between expo-sure and density is the film characteristic curve. The characteristic curve indicatesfilm sensitivity, which is required when determining exposure, film latitude and other :factors important to a obtaining correct exposure. " -

Fig. A shows the typical characteristic curves for color reversal and color negativefilms. As would be expected, these curves indicate opposite tendencies for each ofthe three primary colors, red: green, and blue. We will refer to the composite curve ofFig. B to simplify the discussion here.The X-axis indicates the logarithm of the exposure, and the Y-axis is the transmissiondensity of the film. Color reversal film becomes increasingly transparent as the expo-sure increases, and becomes increasingly opaque as the exposure decreases, pro-ducing an inverted S-curve descending to the right. The curve indicates that exposure ,and density are not proportional at the two extremes (the top and bottom of the curve)'but are proportional through the straight line in between. This straight line indicatesthat part of the film which most accurately reproduces variations in light intensity on . .lthesub jec t . . ' t . t : , ; , ' - ,

This range is referred to as the film's exposure latitude, most commonly a differenceof about five stops between maximum and minimum exposures with color reversal ,:.film. (The area between S and H on the Flash Meter IV contrast scale is the exposure :'

latitude of the film.)At about the center of this range is reference exposure Hm, whichis used to calculate film sensitivity; the intersection at which reference Hm producesmidtone density Dm is film sensitivity M.

With incident light metering, the required exposure is obtained by measuring illumi'nation on the subject. Exposure calculations in this system are designed to reproducean 18% gray subject exposed at the indicated aperture and shutter speed in neutral :.:tones, i.e. at mean densitY Dm. -,In reflected-light metering systems, the light reflected by the subject is measured to ..,,,

determine subject luminance, and exposure is adjusted so this is equivalent to refer- '"

ence exposure Hm. In other words, all subjects, no matter what their reflection factor,will be reproduced as a mean density Dm image. In actual photography, the highestreflection factor encountered for white objects is about 85% to 9Ao/o, and the lowestreflection factor is that of black objects, about 2.5o/o to 3%.

In terms of exposure differences, this range breaks down into about five stoPs ofapprOximately 3o/0,60/o, 120/o,24.0/0, 4Bo/0, and 96%, placing the 18% gray subjectroughly the middle. Accordingly, the exposure indicated by an incident light meter andtheixposure indicated by a reilected light meter using a subject with a reflectionfactor of approximately 18% will be nearly equal under equivalent lighting conditions.lf thepicture is exposed at the metered levels, subjects with a reflection factor of from

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Fig. A Color film characteristic curve

Color negative film

This example approximates an areawith 18% reflectance.Fig. B Composite film characteristic curve

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Ch

etering:

Reflected light metering systems measure the light reflected by the subject. Thereceptor is pointed directly at the subject and thereby measures the actual light(luminance) which will enter the lens and be recorded on fi lm. All scenes contain bothlight and dark objects, and for certain applications the reflected light meter can bemore effective than an incident light meter, the readings of which are based on areference reflection ratio of 18%.

One normally seeks a natural balance in which light objects appear light and darkobjects appear dark. There are, consequently, some problems presented by reflectedlight meters as they will turn both light and dark objects gray in the final photograph. ltis therefore important to meter the right part of the scene to produce the best results.Understanding this principle will enable the photographer to adjust the exposure toemphasize a particular subject, or to add detail to a generally white or dark picture. Inaddition, determining the contrast in the scene and monitoring how certain l ightingconditions are reproduced on film will enable the photographer to use other techni-ques to get the most from the film's potential.

Reflected light meters also permit accurate metering of translucent subjects, neonlights, lamps, and other light-emitting subjects, in addition to metering of subjectswhich cannot be conveniently approached.

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1/3 aperture

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Reflected light metering: Basic operction

Minolta Flash Meter IV operation in the reflected light meter mode is shown below.

, Attach the View-finder 5", the

Viewfinder 10' II orreflected light meterattachment to,thereceptor, or use thebooster.

Set the measuringI mode selector to

the desired meter type.(AMB|, CORD, NONC.)

Set the functionselector to TIME

or FNo. TIME: shutter-priority meteringFNo: aperture-prioritymetering

Use thedecrease/increase

control to select eitherthe shutter speed oraperture (f-number). (fhisshould normally be set tothe flash sync speedduring flash photography.)

r For further details, refer lo the instruction manual.

The biggest difJerence between metering with a reflected light meter and an incidentlight m-e1er is in step 5: in reflected light metering the receptor must always be directedat the subject from the direction at which the camera will be located.

There are two major techniques used in reflected light metering: (1) averaging*, inwhich the entire subject is metered from the camera position, and (2) spot metering, inwhich a narrow acceptance angle is used to meter a specific part of the subject. (SeeFig. 4.)*Care musl be taken so that shadows from the meter or photographer do not cover the subject.

Fig. 4 Relationship between acceptance angle and subject

tIV

Foint thereceptor

directly at the subject

Press themeasunng

button to take ameasuremenl

Bead therequrreo

exposure setting fromthe data panel

A H

oTIMEG VrsoFNo

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Average meteringIn average metering, the receptor acceptance angle (40' on the reflected light attach-ment, 10" on the VieMinder 10o [, 5o on the Viewfinder 5")permits metering of lightreflected off the subject, thereby producing an averaged reading and exposure.

lf the reflection factor of the overall scene is approximately 18%, the exposure willbe equivalent to an incident light metered exposure of the same scene. See photo-graphs A and B.Although this technique produces a quick, easy reading, the exposure will be un-balanced if large parts of the scene are extremely light, dark, or backlit. See photo-graphs C and D.

@' f n Fb

Spot meteringA narrowed acceptance angle is used for spot metering, thus permitting metering of aclosely defined part of the subject. This narrow angle prevents interference from sur-rounding lights and reproduces the metered area as a midtone density. lf the meteredarea has a reflection factor of about 18%, an averaged exposure similar to that pro-duced by an incident light meter will result. See photographs E and F.

With the Flash Meter IV, the photographer can meter either tight (whites)or dark(blacks) areas, and press the highlight (H)or shadow (S) key to retain maximum detailin that part of the subject while maintaining a natural balance on the overall exposure.Accordingly, best results are obtained with spot metering by first determining theoverall comDosition before meterino.

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Subject contrastand exposure determination

The spot metering technique described on the previous page compensates for manyof the problems inherent in reflected light metering and can be used to producephotographs exposed for specific objectives. To really optimize the possibilities ofiettecteO tignt meters and to get the most from the film, the following technique shouldalso be mastered.

This technique involves spot metering of both highlights and shadows, and thendetermining the expoSure from these metered exposures and the exposure latitude ofthe film. In other words, knowing the brightness, ie. luminance, of the subject is themost effective way to reproduce these images on film. This range of subjectbrightness is called subject contrast* (or subject brightness range) and is expressedas a ratio between the highest and lowest luminances on the subject. Subjectcontrast is defined by the lighting ratio and the subject reflection factor'

The Flash Meter IV includes both a memory function and analog scale for easy,visual confirmation of subject contrast. lt is also equipped with highlight (H), shadow(S) and averaging (A) keys which let the photographer determine the exposure bym6nitoring subject brightness before shutter release.For example, the difference between highlights (the wall of the outside building) andshadows (the car radiator grill inside) in the pictures at right is eight stops, or a subjectcontrast of 256: 1. (See Table 2.)

At the same time, howevet the latitude of most color reversal film is approximatelyfive stops with subjectcontrastof32:1 (seepages 16 and 17). Insuch situations wherecontrast exceeds filmlatitude, exposing thescene with an averaged[(A) key]exposure willoroduce washed-outhighlights and darkshadows (picture B).

lf the situation allowsthe highlights to be

Highlight area (memorized)

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0

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Table 2

Difference inmetered exposure(Ex lN.)

Subjectcontrast

1 stop z , I

2 stops A ' 1

3 stops 6 . 1

4 stops 1 6 : 1

5 stops 32:16 stops 6 4 : 1

7 stoos 128:1

B stops 256:1emphasized and theshadows dismissed, press the H (highlight) key to meter for a highlight-weighted expo-sure; all shadow areas below the S mark on the contrast scale will be completely black(picture A). Conversely, if the shadows are to be emphasized, press the S (shadow) keyfor a shadow-weighted exposure; all highlights above the H on the contrast scale willbe washed out (picture C). Refer to the scales and exposures indicated to the right of

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each photograph.

*lt is important to selectively meter the brlghtest and darkest points essential to the composition,not simply measure any two indiscriminate points of maximum contrast. lt is also important toconsider the differences in brightness related to color hues.

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(A) Highlight-weighted exposu re

Exposure. I l11 + 1 14, I /30 sec

(B) Averaged exposure

Exposure I l56+112, 1 /30 sec

(C) Shadow-weighted exposu re

Exposure: I l4 + 1 14, 1/30 sec

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The photographer can judge the subject's brightnesslevel and decide where'jn the film's latitude the tonesshould be reproduced.

In the scene show4 in photograph A-3, the subjectcontrast is 1.5 stops, 'a 3: 1 ratio. The darkest tones werethe shadows in the facq and the lightest tones in thewhite clothes. When the photo was exposed using anaverage meter reading, the white clothes became a lightgray and the face was a slightly darke.r gray, as shown inA-1. When exposed using a shadow-weighted reading,the face was reproduced very darkly, as shown in A-2.Since the most important areas in the scene are whiteor very light tones, it is clear that a highlight-weightedreading should be used to give added detail to the facewithout loss of detail in the white dress, as shown inphoto A-3.

In photograph B, the subject contrast was approx. 4stops, 16:1. The scene was exposed with a shadow-weighted reading to retain tonal detailof the clothes. Bymetering the face, it was determined that it wouldappear lighter in the final results.

The Flash Meter IV will fix the exoosure value on thedigital display derived from an incident or reflected lightmeasurement. Afier taking a measurement, additionalareas can be measured to determine the tonal relation-ship between different parts of the picture. These mea-surements can be comoared on the contrast scale. Forexample, if the face in photo A-3 is to be a midtonedensity, meter the face and press the A key was pressedto lock the reading on the display. Then the clothing andhighlights can be metered and compared with thisreference point to determine how brightly they willreproduce in relation to the face.

Meter the face, monitor the clothes.t

Exposure: fl11 +114.1/60 sec

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(Ihis example shows that the photograph will be slightlyunderexposed compared to photograph A-3)

A-2 Shadow-wei ghted exposure

Exoosure: tl22+112. 1/60 sec.

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A-3 H ighlight-weighted exposure

Exposure: l l56+314, 1/60 sec

75ws

Lxposure. l l9 ' 314 1/60 sec

B Shadow-weighted exposure