Film cameras
Pentax New scan of just the metering pages User manual
User manual for Pentax New scan of just the metering pages. 18 pages in English. Read the original PDF, download or print a copy without registration.
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- Brand
- Pentax
- Model / document
- Pentax New scan of just the metering pages
- Document type
- User manual
- Language
- English
- Pages
- 18
- File size
- 1.4 MB
- Category
- Film cameras
- Document date
- Not specified in catalog
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Page 4 · Read text
The10l21o Meter is extremelysimple to use. Nevertheless,you should read the in-
structions beforehand.For those in a hurry, a good start can be made by examining
the illustrationsidentifyingthe externalparts, and by following the ABC's of opera-
tion. A more thorough reading of this booklet should follow later.
. " i ; .
A short ABC of Exposure Readings ;-:
with your Honeywell PentaxIol2l" Meter t
A. Set the ASA scaleto the correctfitm speedratingof the film you'reusing.
B. Hold the meterin your right hand (with viewingocularcloseto your eye)and
directmetertowardphotographicsubject.
c. Centerthe smallcircleon areaof primepictureinterest.Observeon the H scale
of the viewingscreenthe light level(L.L.)numberat whichthe needlecomesto
rest. lf the levelis less than 10 on the H scale and/or the needteis not de-
{lected,then pressthe "L" buttondown and observethe L.L.on the low range*
indicatedby L scale.
D. Set this observednumberbelowthe silverindexmarkon the metercalculator
by turningthe knurledouterring.
E. Selectthe shutterspeed and f/stop combinationdesired(from the two top
scalesof the metercalculator)and transferthis datato your camera..
xlmportant-Refer to Low Liqht phenomena-section ib
@ 1966Honeywell,tnc., Printed in U.S.A.View original page 4Page 5 · Read text
Honeyvuell Pentax 1'/?-1o cds
secti o n clxposiLrFe rrreten
2,
a. Dbsign-The 1o 121"meter is a
rugged, portable,practicalexposure
meter for on-location or in-studio
use.The meter is light in weight and An L.L. (Light Level) scale is lo-
is designedfor raPid,one-hand oP- cated beneath the viewing screen
eration.The changeoverfrom read' below the circle in large black num-
ing high to low levelsof light inten- bers which can be easilYread, even
sity is instantaneousand requires under low levelsof brightnessof the
no change of positionwhen holding o b j e c t b e i n g v i e w e d o r P h o t o -
the meter. The meter is essentially graphed. The scale is essentiallY
a single-lensreflex optical system, self-illuminatedand will prove ad-
consistingof an objectivelens and a vantageous to PhotograPherswith
reflex viewing system with a 1.5x eye- a vision problem as well as to the
piece or ocular.The viewing screen a v e r a g e p h o t o g r a P h e rw o r k i n g i n
covers a viewing angle o121"and in dark locations.
the center of the screen is a circle The scales located on the meter
definingthe 1o angle of acceptance calculatorare engravedin three col-
of the cadmium sulfide light sensi- ors for good visibilitYand ease of
tive element. reading. 18
www.orphancameras.comView original page 5Page 6 · Read text
The external design of the 10 l21o
meter is clean, contemporary, and
functional.The hand grips its pistol
shape in a mannerthat affords com-
fortable ease of use. Eye-levelview- The internal design characteris-
i n g m a k e s s u b j e c t l o c a t i o n a n d tics assure long life through rugged
metering of a fast-moving subject a construction. The basic chassis is I simple task. The high range of the made from cast aluminum covered
meter will function with removal of with a molded impact-resistantma-
t h e l e n s c a p . T h e i n d e x f i n g e r i s terial. The brackgts supporting the
automatically led to the ,,L,' button e l e c t r o n i c c o m p o n e n t s a r e t h i c k
where low range readings can be brass or steel fixed in position with
made quicklyand without fumbling. brass screws. Both battery cases
R a i s i n g t h e i n d e x f i n g e r a p p r o x i - are spring loaded and of extra heavy
matelyllinch will bring it to the ,,B" construction which will preventcon-
button which is used to check the tact failure. Positive and negative
battery.All this can be accom plished terminals of both compartments are
w i t h o u t m o v i n g t h e e y e f r o m t h e clearly marked to prevent improper
viewing screen. replacementof the batteries.
At the base of the meter is a tripod A l l e l e c t r o n i c c o m p o n e n t s , i . e . ,
socket which is also used for a neck g a l v a n o m e t e r ,c a d m i u m - s u l p h i d e
or wrist strap providinga secure and cell, and resistors, are of selected
easy method of carrying the meter. quality elements. 1 9 t i .
I iView original page 6Page 8 · Read text
identification of extennal pants
1) Objectivelens 10)ASA scale
2) Zero adjustmentscrew 11)Inbexfor ASA scale
3) Battery checker button 12) Light-levelscale 'L'switch
4) buttonfor low light 13) Indexfor light level
5) Adjustableeyepiece 14) Batteryhousing cover
6) Shutter speed scale 15) Outer ring for matchinglight level
7) Diaphragmscale 16) Film-speedsetting plate
8) DIN scale 17)Nipplefor turninginner disk
9) Indexfor DIN scale
21View original page 8Page 9 · Read text
carriesvaluesfrom 3 to 10,and the
high levelrange(H),abovethe line,
carriesvaluesfrom 10to 18.In sub-
dued light the (L) Low rangeof the
scale is used.(lmPortant: This
s c a l e s h o u l d n o t b e c o n f u s e d
b. The Scales-The 1" 121"scales with the EV or ExPosure value
are designed with ranges of shutter system used on some cameras
s p e e d s , f / s t o P s a n d A S A f i l m and shutters.)The numberson the
speeds above and below the limits L. L. scalearea convenientseriesof
of today's cameras,which is built-in numbersexpressinglight intensity
insurance that your meter will re- or "light level" for the 10121"meter
m a i n a h e a d o f o u r e v e r - g r o w i n g only and cannotbe transPoseddi-
technology. rectly to camerasor shutters with
T h e e x p o s u r e c a l c u l a t o r o f t h e the EVSor LVS systems.TheremaY
meter includes two movable rings. be instanceswhen the values,be-
The first scale located on the outer cause of a certaincombinationof
ring at the bottom of the calculator the variablesof lightand f ilm speed
(12) is the L.L. (Light Level), scale of the {ilm you are using,would re-
and is markedin numbers from 3 to sult in the L. L. numberbeingthe
1 8 . T h e s e c o r r e s P o n d t o t h e L . L . sameas the EVS number;however
scale on the viewing screen. The this would be purelycoincidental.
low level range (L), below the line'
??
www.orphancameras.comView original page 9Page 10 · Read text
The secondscale"T" locatedon triangleas an aid to motion picture
the outer ring at the top of the cal- photographers,who maywishto use
culator (6) shows shutter speeds this as a point of departurein ob-
from 4 minutesto 1l4OOOsecond. tainingreadingsfor movieuse.1/30
The silvernumbersare fractionsof secondis the shutterspeedfor most
a s e c o n d% , % , % . . . 1 1 4 0 0O0r.a n g e 16mm movie camerasoperatingat
numbers2,4 . .. 30arefull seconds. 16framesper second.(SeeSection
Orangenumberswith a smallm be- 8 for motionpicturedata).Interme-
side representfull minutes.1/b0 diate shutter speeds other than
secondis markedby a smallorange ASAstandardspeedsare shown:
40 20 l0 5 2.5 t.2 1.6 : 6 40 50 1%Ml%M 2%M3ht
Shutter speed Scale "T"-Time
adjacentnumbersrepresentdouble
The DiaphragmScale ,,F" located or halfthe amountof lightadmitted.
on the inner rotatingdisk (17),con- Since f/numbersare fractions,the
tains lens diaphragmf /numbers higherthe number,(actuallya de-
Irom t11to f 1128.Numbersmarked nominator),the smallerthe aperture.
are ASA Standardf/stops and each Otherintermediatestopsare shown
interval repres'entsa full stop, i.e. on the followingscale.
l9 11 20 28 10 56 80 ll2
D i a p h r a g m S c a l e , F ' - f / n u m b e r s o f l e n s d i a p h r a g m .
P3View original page 10Page 11 · Read text
The inner rotating disk also has two grees from 10to 11" is a logarithmic
film speed scales.The orange scale series, base 2, and designates the
calibratedin ASA, the green in DlN. same film sensitivitiesas the alter-
The I ndicesfor the film speedscales nate arithmetic series 6 to 6400.The
as well as the L.L. scale are respec- log seriesin degreesis called "film-
tivelycoloredtriangles(9, 13 and 11) speed values" to distinguish them
on the innermostnon-rotatingdisk. from the arithmetic "film speeds."
The ASA film sPeedsare calibrated The two series do not exactlYco-
i n t h e f a m i l i a r a r i t h m e t i c s e r i e s . i n c i d e ; h o w e v e r , t h e c o n v e r s i o n
These numbers again relate to {ull shown is sufficiently accurate for
f/stop values which are an indica- g e n e r a l u s e . N o t e : D o u b l i n g t h e
tion of the f ilm sensitivity.The cali- A S A f i l m s P e e d P e r m i t s c l o s i n g
brations on the ASA Film SPeed down 1 {/stop; halvingthe ASA film
Scaleand the intermediatenumbers speed requiresopening up 1 f /stop.
indicated by marks between the en- Addition or subtraction of 1 to an
graved numbers are shown below. ASA degree value is equivalentre-
The new ASA film sPeedvaluesare spectively to a decrease or an in-
also shown. This series o{ ASA de- crease of one f/stoP.
{0 80 160 320 640
A S A F i l m S p e e d S c a l e
24
www.orphancameras.com
. - - - i : : - , - . : t s r lView original page 11Page 12 · Read text
c. Reading the Meter the 10 on the H (high) scafe, which
1) Turn the inner rotating disk (16) covers light levels 10 to 1g. lf the
by means of the nipple (17),and set light level of the subject is less than
the film speed, ASA or DlN, to its 10 and the needle does not move far
respectiveindex (9 or 11). enough to the right to reach 10 on
2) Remove the lens cap and turn the H scale, press the ,,L" switch
the eyepieceto adjust it to your eye- button. This places the meter in the sig ht. second or low range indicated by
3) The subject is selected and lo_ the "L" scafe. Numbers from B to 10
cated within the 21oviewing angfe on fall in this range. IMPORTANT, do
the screen. Note that the image is not push the " L" button putting the
erect and unreversed. The center meter on the low range, until you
circle of the viewing screen covers have determined that the tight levelis
an angle of 1o in which the meter's below 10. lf the"L', switch button is
Iight sensitive elements function. depressed in bright light the needle
T h e s p e c i f i c a r e a t o b e m e t e r e d will read off the sca/e and this may
should be centered within the 10 damage the meter movement.
circle. 5) Observe the L.L. or light level
4)With the removalof the lens cap number from the position of the nee-
the 10l21o meter reads high light in- dle on the scale.Move the outer ring
tensity. lf the area of subject within (15), and match with the light level
the circle is sufficienfly bright the i n d e x ( 1 3 ) ,t h e s a m e n u m b e r o b _
needle will then move to the right of tained from the light level scale on
25View original page 12Page 15 · Read text
e. Low Light Level Phenomena-
1) Photoconductorconditioning-
W h e n t h e m e t e r i s t o b e u s e d t o
read very low-level subject bright-
ness, and the caP has been in Place
on the meter, it is advantageousto to some degree,dePendingon the
"condition" the meter by viewingan frequencyof use. ExPosureto a
object of slightly greater brightness brighterobjectfor a secondor two
than the subject of interest.As long will permitinstantaneousreadings.
as the object is within the 1o circle, One precautionis advised-expo-
the dual-rangebutton does not need sure of the Photoconductorto an
t o b e d e p r e s s e d .O b v i o u s l Y ,i n a extremelybright light will resultin
studio situation,leavingthe cap off over compensation,i.e.,when the
betweenreadingswill keePthe me- meteris redirectedto the low level
ter conditioned.The advantage of subject,the needlewill stoP at aP-
this "conditioning" of the cadmium proximatelyoneL.L'unithigher,and
s u lf ide crystalis si m p ly a time-s aver' then slowlY move to the left and
becauseif the dual-rangebutton is come to rest on the correctvalue.
held down, a low level reading will This maytakeas long as a minute.
be reached without "conditioning" The importanceof good judgment
in about 2 to 3 minutes {or a meter being used in choiceof an object
is reduced ject is thereforeobvious.I whichhours. hasThe beentime constantcaPPed for several only slightlybrighterthan the sub-
2A
L . www.orphancameras.comView original page 15Page 16 · Read text
2) Dampening-Thetime constant
for those phenomenaand speedof
the needlemovementin general,as
well as fluctuationsof the needlein
scanningsubjectsof variedbright-
ness levels,are functions of the
dampeningeffectof the individual
meter.Thesevariationsareinherent
Example:1) Photoconductorcondi- in any electronicinstrument.
tioning-Metercap on for t hour; 3) Drift-lf the needleis observed
time requiredto reach readingof to drift,i.e.,theneedledoesnotcome
L.L. 3.5-3 minutes. to restwithina reasonableperiodof
Conditioningby exposureto L.L. time, providedthe light source is
6 valueobject-approximately1 sec- constantand the meteris held in a
ond;timerequiredto reachreading rigid, fixed position,batteryweak-
of L.L.3.5-approximately1 second. ness is indicated.
29
.--at:,-.))E -.r.:,View original page 16Page 17 · Read text
f. Mechanics-replacing batter- batteries to fail eventually even with
ies, etc. n o u s e , a n d t h e o u t p u t s l o w l y d e -
1) Zero correction-The 10l21o me- creases as the batteryages. The life
ter will retain its accuracy with an depends upon the qualityof the dry
a b s o l u t e m i n i m u m o f a t t e n t i o n . cell and how much it is used. The
Should the needle ever not lie ex- life expectancyis six months to one t
actly on the zero mark when at rest, year for the 9V dry cell.
zeroing is easily accomplished by 3) How to test batteries-The bat-
turning the adjustment screw above tery checker button (3) checks the
the battery test button. l i f e o f t h e 9 V d r y b a t t e r y . L o o k
2) Battery life and method of re- through the viewfinder,and depress + p l a c e m e n t - T h e 1 " / 2 1 " m e t e r i s the battery checker button. lf the
powered by two batteries-one 1.3 needle moves to the black mark be-
volt mercury battery and one 9 volt tween the f igures 7 and 8, the dry bat-
dry cell. The mercury battery oper- tery is still active.lf it does not move
atesthe high range,"H,"and the dry to this mark, replace the battery.
c e l l o p e r a t e s t h e l o w r a n g e , " L . " The mercury battery usually lasts
The life of the mercury battery is for about a year.When it is depleted,
very long at a uniform levelof output t h e n e e d l e w i l l n o t m o v e r a p i d l y
untilfailure.Lengthof life is depend- against bright light. lt should usu-
ent on frequencyof use,but it should ally be replacedafter one year's use.
be replaced after one year's use. When replacing batteries, use the
I t i s a c h a r a c t e r i s t i c o f d r y c e l l correct replacement batteries.
30
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