flash meter iv user guide

FLASH METER IVUSER GUIDE

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#wrst*ntsIncident 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 processin 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 rthe 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)


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.

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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.

' ,"]; - I Set rhe modes, I selector to the

oeisiirio meter type.(AMB|, CORD, NON. C.)

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

,"- '" i i - ' ; 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 IVnear 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 : 14 stops 1 6 : 15 stops J Z . I

6 stops 64:17 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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Chetering:

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 lightingconditions 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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Reflected light metering: Basic operction

Minolta Flash Meter IV operation in the reflected light meter mode is shown below., Attach the View-

finder 5", theViewfinder 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 subjectt

IV

Foint thereceptor

directly at the subject

Press themeasunng

button to take ameasuremenl

Bead therequrreo

exposure setting fromthe data panel

A H

oTIMEG VrsoFNo

20 www.orphancameras.com

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.

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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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Table 2Difference inmetered exposure(Ex lN.)

Subjectcontrast

1 stop z , I

2 stops A ' 1

3 stops 6 . 14 stops 1 6 : 15 stops 32:16 stops 6 4 : 17 stoos 128:1B stops 256:1

emphasized 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 '

,'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

m

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

=#a ':Eh ":-"

(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.


@ - 3

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

Monitoring subject contrast with reflected light metering as described on thepreceding page is a particularly effective means of adjusting lighting to controlreflections, to depict of translucent objects and to accurately place of highlights andshadows. Consider the. scene on the page at right.

To emphasize the tones of the purple glass illuminated by light from below thescene was metered with reflected light metering and thereading locked with the A key. The blue glass on thetransparency beneath the purple glass and the brightwhite were then monitored.

These readings showed that when the exposure isweighted for the purple glass (which then becomes the0 reference), the white areas will appear as highlights onthe printed film and the blue glass will be reproduced atapproximately the same density as the 0 reference {orthe purple glass.. Meter the purple glass ('A' key)

tl32 + 112,1160 sec.- 4 . . 3 s . . 2 . { . O . I . 2 x . 3 . 4 .

, f i lCr f i FNd E. E l i J - a r " o " or s o E U \ J L : '

being a bright white.

- 4 . 3 s . - 2 . j . 0 . I . 2 r . 3 . 4 .

i r d r f l F N o E- n U ] J - , c o n o

r s o ! - u \ J L - l

Exposure: i l22+ 213.1/60 sec

. Monitor the white highl ights------ l

z i t

E r n u [ l

#_\ Jls"'""Another application is demonstrated by the photograph beiow. Here the exposure wasdetermined with incident light metering, then the digital display was locked by pressingthe 'A' key. The tiles and shadow of the can were then monitored with reflected lightmetering to confirm that colors would appear in the shadow with the remaining tiles

.lncident l ioht measurement ( ' .A' key). Monitor the white areas on the t i les

4 . . 3 E . 2 . I . O . | . 2 r . 3 . 4 .

5 i r e r l F r o A --nU

1 7 -r.o,oE , ' , \ J L J

. Monitor the f ront t i les

- 4 . - 3 s . - 2 . j . 0 . I . 2 r . 3 . 4

*r-5il '*" l^l - "oh Jl_]""""

@!9

2500ws

b2500wsl i lm

Contrast control

When the subject contrast exceeds the latitude of the film, shadows or highlights areoften sacrificed the composition (see page 23). Both in the studio and out, lighting canbe controlled to adjust subject contrast without losing any detail in the picture. In thescene at right, the outside is brighter than the inside (the contrast is high), and thesubject contrast exceeds the film latitude.

lf the exposure is adjusted for the outside, the model and car will be too dark asshown in photo C at the bottom right. Similarly, if the exposure is adjusted to the inside,the.outside will be grossly overexposed (photo B, bottom left). In such situations,daylight synchronized flash* will add light and decrease the contrast, producing photo-graph A. In short, additional lighting (flash light in this case) lowers the subject contrastto within the film latitude.

Metered outside (memorized)

ffi'lr, ^-;Metered indoors, on face

ffi '1"r"-^-;Metered indoors, on face withsynchronized f lash

o 3

@ t f l b

In the photograph (A)the natural (ambient) light outside is metered, the flash is thensynchronized to fill the shadows inside and lower the contrast to approximately 2: 1 sothat the background is slightly overexposed. Shadows (on the radiator grill), the model'sface and highlights (on the wall)were then monitored with reflected light metering.

Shadows monitored

ifrl,Fn F& ^ '

N L i ? F*jr-\ J.D ?"o""

*Daylight flash sync is a process is which sunlight (ambient light) and flash light are both used inthe exposure. The analyze and memory functions of the Flash Meter IV are very effective whenphotographing scenes using both daylight and flash light.

II6iI

t

(A) Exposure: f/5 6, 1/60 sec


Creatimxrng a

measurement:flash lighting

Mixing ambient light with a flash and an orange filter can effectively create a twilightatmosphere on cloudy days. In the photograph right, exposure was balanced for thebackground.

The hat was then measured and a strong flash added to enhance contrast andaccents, turning an othenruise non-descript, cloudy sky into a bright evening sky withsunlight slanting down through the clouds.

. Flash exposure was meterd.

oEg

t* '1fr fl.fr fr*.". Measure ambient l ight

T r '""q1J,.,o""'* ,..11

\ f. L, I

EXposure: Il5 6 + 112, 112 sec.

Mixed lighting control:neon and flash lighting

Flash light was added to the model holding a blue neon tube and the greenneon light in the background was moved throughout the one-secondexposure to create a flickering effect.

The model's face and legs, illuminated by both the blue neon light andflash, were metered. The analyze function was then used to determine theratio between ambient and flash light on the face and legs to adjust thelighting. Flash intensity was decreased to emphasize the blue light from theneon tube.

On face

4 Z

@

4 Z I . 0 . I . 2 x . 3 . 4

@ t uI J D . .

m-;- i \ f ,J ,q {oNcf i 1

On legs

f t m 1 3t \.fr tE UU I

Exposure: I l2B+112, 1 sec


The model's body and the flowers were illuminated with a spot flash, letting light fromthe television screen illuminate the face.Using the analyze function, a measurement of the model's face indicated additionallighting was needed on the body and flowers; the spot flash was positioned to helpaccent the face.

The Flash Meter IV handles such assignments easily. Conventional meteringtechniques have a hard time determining the effect that subtle changes in lighting willhave on exoosure comino from sources such as a W screen.Reading on face

r . l i . - z . u ! 6 . t . 2 " . 3 . 4 -@ , 8 F MI r r* El_l J.A ,/"o""

Reading near waislt - r - .r . . 3 . . - 2 . { , . \ 0 . 1 . 2 4 . 3 . 4

,fi[E] , s F&

=-=-f---. t/ fl 7**.' ' - h I \ r ' r ' t L

Reading on flowersI r l !- 4 . - 3 s . - 2 . { r D . 1 . 2 x . 3 . 4

@ , s F &I r r%Y_l J.D 1"o""

Exposure: Il4+112, 1 sec.34

b1 5OwsBo*! &


A sense of dynamic action was captured bymoving the camera during a one-second expo-sure under mixed lighting consisting of a bluefilter over a tungsten light and normal flash. Whilethe blurs are accented highlights illuminated onlyby the tungsten, flash light was added when thecamera was stopped.

The analyze function was used to determinethe illumination and color reoroduction of themotorcycle while the camera was still. The bikewas almost completely exposed with a 1/30 sec.exposure following shutter release and prior tocamera movement. With an f/5.6 aperture, thetungsten light had virtually no effect on colors.

i - r , . - . . . . i ! i . , . 2 , . 3 . 4 ^@ ' t f i F &

_fr-f r f* t;i_1 J.A J*""- a . _ 3 , . - 2 . l i . i . 1 . 2 " . 3 . a ^ '

f u e , s F M-rih fl.n.'*".

Blu€ f i l ter\'gN, o h3n)N Z E V-

Exposure: fl5 6, 1 secwww.orphancameras.com

Cu m u lative exposu re meteri ng

The first exposure captured the blues of the blinds. Thesecond exposure turned the spaces between the slatswhite and caught the tire peeking through from thebottom. In the third exposure, the blinds were removedand the bicycle was exposed as a blue silhouette.

Cumulative readings with reflected light meteringenabled the photographer to control the contrastbetween the slats and monitor the exposure of thoseareas silhouetted by the bicycle through the blinds andthose areas not silhouetted.

The digital display indicates the integrated value ofthe three exposures creating the bicycle silhouette. Thepointer above f/45 on the analog scale indicates the partof the slats which will not be silhouetted; f/90 is thecumulative exposure for the spaces between the slats.

-TE{- rr:J";";-;::i,Exposure: 1st

2ndBlinds exposed blueTires visible through blindsexposed: illuminatton frombehind the bl inds; blue l ights infront extinguishedBicycle silhouetted: whitebackground l i t with blue l ights;blinds have been removed

Cumulative exposure metering: Mul

To il luminate these large buildings with a small f lash (GN32), the tables were exposed by firing a flash 8 times.The building was exposed by firing a flash 22 times withthe flash unit as shown in the figure below.

The tables and patio were metered eight times withincident l ight metering and the cumulative readings; thebuilding was metered 22 times with the reflected lightmetering and the cumulative readings.

The exposure was adjusted so the background wouldbe slightly underexposed because ambient light has aneffect on the exposure during the duration. Flashrecharge per exposure was 8 seconds with the cameraset at "bulb'i

I Ki\l v e q e \ - / '

Guide number: 32

Meter the building

1 1 4 2 2 8 4 5 6 8 I t 1 6 2 2 3 2 4 5 6 4 9 0 !

@ i ' ? s , F Mn L r r;;--- --r lJ -, I? : NoN c*

f r u , \ - _ t . L f L uu , r , +fi?''v.ll','*,,Exposure: f/5 6, bulb exposure (approx 4 min )

Flash fired B times towards the tables, 22 timestowards the buildinqs


Cumulative exposure metering of this scene indicatedmost objects would be fully exposed with the first andsecond exposures, leaving the lamp-lit miniatures to befinished with ambient and flash light. The miniatures onthe chair were illuminated by both the lamp light andblue-filtered flash light. The miniatures on the chair wereslightly overexposed, compared with the edges lit onlyby the flash.

In the third exposure, the photographer sought to flarethe light coming through the openings in the chair andilluminated from behind. An aperture-priority cumulativereading indicated that the flash should be fired fourtimes with the lens at f/90 to overexpose the gaps byabout three stops compared with the main lighting in

lst exposure reading

1 C s* J f l " l , ' * 3 3 - . o " o' " o . i , / \ ' L L f " u . r ,

Cumulative reading of 1st and2nd exposure

lrr"r'^fut

Yellowf ilter' lD2400ws

'tg'u $

3#--,.1'"r r l,-"3rd exposure reading

rThrsr,;:Exposure: 1st Exposure made with a

small tungsten lamp on thechair and f lash l ight withblue filter.

2nd Exposure from small standlamp on chair top: softeffects filter on lens.

3rd All lights on chair turned off;i l lumination f rom back-ground f lash with yel lowfilter; soft effects fllter onlens

tl22+ 112,30 sec.

tl22+112,30 sec.

tl22+1l2,"bulb"exposure; flashfired 4 times.

exoosures one and two.


Booster II and attachments

The Minolta Booster II is a TTL exposure meter cellwhich permits direct metering of low light levels usingany of the Booster II reflected-light receptors. Thereceptors enable direct metering via Flash Meter [V* oflight levels which cannot be metered with a flash meteralone.

Some examples: brightness at the focusing screen oflarge format cameras, at the film plane of SLR camerasor at the eyepiece of the viewfinder, in the eyepiece of amicroscope and other applications in which light hasalready passed through an optical system.

The booster's cable plugs into the accessory jack onthe Flash Meter IV, and the spot-probe attachment, SLReyepiece attachment, microscope receptor or 35mmfilm olane attachment is attached to the booster. One oftwo metering techniques is used:

Fixed aperture meteringIn this technique the aperture is preset. The meter reading can be read from the FlashMeter IV data panel as when metering with Flash Meter IV alone. This techniquecorresponds to exposure measurement at open aperture. and is used with the spot-probe attachment or SLR eyepiece attachment.

Stop-down meteringAs the name implies, the aperture is stopped down to the desired aperture and theshutter speed or guide value (GV) is read when the Flash Meter IV indicates a specifiedaperture. This technique corresponds to stopped-down, TTL metering and is used withthe 35mm film plane attachment or microscope receptor.

When first using the booster, it is also necessary to obtain the ccjinpensation factorindicated on the compensation scale according to the optical characteristics of thephotographic equipment used, including the camera and lens.lf the same equipment and materials for which this compensation factor is determined,are used, TTL metering is possible under the same conditions as reflected lightmetering.

. For details refer to pages 48 and 49 and the Booster II instruction manual.* The Booster II can also be used with Minolta Flash Meter III, Flash Meter II, and Auto

Meters III. IIIF. and II

Spot-probe attachment SLR eyepiece attachment 35mm film plane attachmentMicroscope receptor

Taken with large format view camera(using spot-probe attachment)4 x 5 view camera.fl32. 11250 sec

Photomicrograph (10X objective, 10X close-up lens)(using microscope receptor)35mm camera; using polarizing light

Macrophotography with 35mm SLR, magnif icat ion 3.35X(using SLR eyepiece attachment)35mm camera: f /11. 1/60 sec

Low i l lumination exposure(using boosted sensilivity. ref lected light receptor)4 x 5 camera (with UV f ilter), 1122, 12 min, 30 ws ultra.viotet liqht source


with the spot-probe attachment:wqr/ camera exposures

TTL metering within a 5mm diameter circle on the focusing screen of a view camerais possible by attaching the spot-probe attachment to the Booster II. Commonly usedin product photography, on-screen metering with the spot-probe permits accuratemetering of the exposure and subject contrast without calculating exposure increases.Even more precise measurement is made possible by using three choices of exposure(highlight biased, shadow biased and averaging).

For example, the photograph at right was taken with illumination shining through theglasses. The spot-probe attachment was used to carefully meter the subjects andvarious locations in the background to determine the exposure so that subject contrastremained within the latitude of the film. To emphasize the tones of the bird, the birdwas metered and key [A]was pressed to lock the reading. Numerous spots fromhighlights to shadows in the background, various parts along the stem of the purpleglass and the glass with liqueur were all then metered.

Purple glass steReading: Glass bird

1 . 2 n . 3 . 4

* llo , '-"

JtJ coRo- i f i l J t r -5

- 4 . - 3 . . - 2 . - r . O . | . 2 H . 3 . 4

*"-ffi'--7'l 5"o*or4.-3s . - 2 . - 1 . O . | . 2N . 3 .4

* l,-to,

'* J^J coRo-q r | 7E I

Blues in the packgroundt

- 4 . - 3 s . . 2 . - l . O . t . 2 6 . 3 . 4

,flte , -r FNo E

4r1 1l-q'o'.

Green liqueur

- 4 . - 3 s . - 2 . - i . 0 . 1 . 2 r . 3 . 4

* llO

,*o J"-l coRD

%t_l 1( 5

Exposure. t l32+112,1/125 sec.

Reading:-Flash Meter IV withBooster II and spot-orobe attachment

Background highlights

Background shadows

* l.'o Ft{o E-t 't coRoJ ( 5t"" 5 rl

Blue in center glassI

. | . 2 H . 3 . 4 .

E'1 't coRD7 (5

-4. -35 . - 2 . - t .

* lln

FNo''o -5 fi

46

Booster compensationThe Booster II contains a built-in increased sensitivity feature which boosts metersensitivity in 1/3 stop intervals; when the compensation dial is set to C, sensitivity isboosted five stops; when set to H, sensitivity is boosted approx. eight stops.

Booster sensitivity matches that of the Flash Meter IV when the dial is set to L, !:allowing the booster to be used as a reflected light receptor with a 60o acceptanceangle by extending the receptor hood.

The difference in sensitivity between optics of the photographic system and spot-probe attachment must be determined with the booster set up as a reflected lightmeter before using the spot-probe attachment. After calibrating the booster, the sceneis metered with either fixed aperture or stop-down metering.

Fixed aperture meteringCalibration

'1. Set the sensitivity dial to Land meter a flat surfacewith even reflectance* usingreflected light receptor. Jotdown the reading.

*The surface should be an evenlyilluminated surface, such asawall, large enough to cover theangle of the lens to be used.

Metering: Fixed aperture

2, Direct the camera at the 3. Set the spot-probe attach-$ame even reflectance ti.:,'. ',1. ment to the focusing screen

, surface and hold it firmly. and turn the compensationFocus the lens at infinity ' ' . .i dial until the readingand close the aperture to matches that noted inthe desired setting. ;,,:.' , step 1. ' , ; : r,e Setting the dial to H may in

some circumstances not besufficient. lf this happens,increase the ISO setting onthe Flash Meter IV until thereadings match or use the

iJ:f,ffiyJ meterinso Block any light which does

not come directly throughthe lens when metering onthe focusing screen.

The compensation dial should be set to the position determined in step 3 above before metering.As the compensation factor differs according to the lens in use, the compensation factor has to be

Adjust the camera and lightsand set the lens to theaperture used when : :. : j:.:, :;:calibrating the booster.

Set the spot-probe atl&sh- ,:ment on the groundglass andtake a reading. Readings indi.cated on the Flash Meter IVdisplay can be used as is. :

48

Stop-down metering

CalibrationCompensationbelow:

Adjust the camera and lightsand close the lens to thedesired aperture. .;

required for the stop down metering mode is determined as explained

1. Set the sensitivity dial to L. and meter a flat surface :: l, with even reflectance* :-' using the reflected light

receptor. Jot down thereading.

*The reading should be a shutterspeed and aperture smaller thanthe full lens aoerture.

3. Set the spot-probe attach* .ment on the focusingscreen and meter with theshutter speed noted in step1. Turn the compensationdial until the display on theFlash Meter IV indicatesthe same aperture setting.

o Block any light which doesnol come directly throughthe lens when metering onthe focusing glass.

MeteringThe compensation dial should be set to the position determined in step 3 above beforemetering. (lf the booster is calibrated in fixed aperture metering with an f/5.6 aperture,that setting on compensation dial can be used in stop-down metering, too.) ..,

2. Direct the camera at thesame even reflectancesurface. Focus the lens atinfinity and close the aper-ture to obtain the samereading as in step 1.

Set the spot-probe attach-ment to the groundglass andtake a reading. Use theshutter speed or GV readingindicated when the display onthe Flash Meter IV for correctexposure.o Either aperture-priority or ,.:

shutter priority metering canbe used. lf aperture-prioritymetering is used, set theFlash Meter IV to FNo.mode. Use f/5.6 to take thereading.

hi i


Wireless remote data transfer viathe Data Receiver DR-IOOO

The Minolta Flash Meter lV is the world's first hand-held exoosuremeter to incorporate an on-board infrared transmitter which permitswireless data transfer and camera control from a distance.By attaching the Data Receiver DR-1000 to the Minolta 9000/MAXXUM 9000 (or 7000/MAXXUM 7000), the user can a'utomaticallytransfer the correct meter-derived aperture and shutter speed to thecamera, then trigger flash and release shutter...a tremendous time-saverin studio situations!

Wireless triggering of flash byIR ReceivenTrigger

Wireless triggering of flash is made possible by using the optional lRReceiver-Tri g ger. Th is versati le accessory f rees photog raphers f romtroublesome handling of the sync cord.Simply attach the lR Receiver-Trigger to the flash, then the flash can betest fired by pressing the measuring button on the Flash Meter lV.


flash meter iv user guide

Documents

flash light

light attachmentwww

light meteringlncident

reflected light attachment

ratio of reflected light

incident light meteringsystems

continuous light sources

instantanieous light