Camera Fundas

8/12/2019 Camera Fundas

http://slidepdf.com/reader/full/camera-fundas 1/22

BRIDGING THE GAP BETWEEN FILM AND VIDEO

There are a number of things you can do to your project to make it look more like film butplease don't fool yourself into believing your cheap miniDV camcorder is any contest for 35mm

film or else you will be sorely disappointed.

. !se lighting creatively in your project. "y this # don't mean just turn on

a lamp. $hen you've seen any film on the big%screen you will notice that lighting is usedeffectively to create a mood. e.g. lighting under a characters face to make them appearmenacing. This is one of the major things cinema%goers subconsciously look at which tellsthem they are watching a film. &oorly lit projects will tell your audience straight away that it isthe work of amateurs.

. !se movie%like camera moves. (kay) that's a bit vague. "y this # mean

hold%off the *oom button during a shot. #n fact unless you re+uire a ,snap%*oom, for aparticular effect within your shot) don't touch the *oom button. #t looks cheap. #t looks shit.-ever use it unless it is to frame your shot. ollywood blockbusters rarely use *ooms. /owatch your favourite movie on DVD and count the number of times you see them *oom in. #

bet you it's less than three times at most.

(ther than the *oom button) learn about panning and tracking shots. 0or e1ample to open ashot you might want to follow a person's feet and move up the body to reveal them ratherthan just sticking a camera in their face. #t's the little touches like this that make thedifference.

3. 2earn about those camcorder settings that frighten you

41posure iris6) focus and white balance % they are amongst some of the most importantsettings on your camcorder and you need to know how to use them. 0ailure to adjust thesesettings according to your shot will again sound the sirens of ,amateur,.

#n a nutshell) the iris controls the amount of light getting into the camcorder so if it is a really

bright day you'd want to turn it down or else everything will be drowned out in white76. This isalso known as e1posure.

0ocus) well you should really know what that is) but what you choose to focus on will make thedifference between the amateur and professional. #t's all a +uestion of creativity. 8nd by theway) you should really turn (00 the auto focus.

8nd finally the white balance is an image control which helps your camera decide what colourwhite actually is. This might seem strange) but in all that technical wi*ard gadgetry) to get thebest colour reproduction from your video camcorder you need to help it get on its feet. !suallyall you need do is mess around with settings within the menu to point it in the right direction."etter camcorders allow you to point your camera at a white object and click a button % farmore accurate and far more professional. (f course you don't have to change the white

balance but then don't be surprised in that yellow flower you've been filming all day looks adifferent colour.

Depth (f 0ield is also a major factor in getting that ,film%look,. 9lick here to read more.

:. Don't use the camcorders ,digital effects, #f you have a lower%end

camcorder you will have noticed that you can add fancy effects to your footage like mosaic orspiral) or any number of tacky transitions. Don't use any of them. They all look really bad andwould look more at place in an awful wedding video. The only transitions you'll ever tend to

http://www.stormforcepictures.com/theshoot-depthoffield.php

http://www.stormforcepictures.com/theshoot-depthoffield.php



find in most movies is either a fade or a cross%dissolve yes ;tar $ars had some differenttypes but hey) that's ;tar $ars76. -ever use built in effects as you can't change it later. #f youmust alter the image in any way) do it later on the &9 so you can ,undo, it if it turns out bad.

5. ;hoot using a &82 camcorder (kay) this is where we get a bit more

technical about the look of film. Video footage is made up of a number of still images all

thrown together to make it appear that the images are moving. &82 camcorders 4uropepredominantly6 shoot 5 images a second and -T;9 camcorders !; predominantly6 shoot at just over 3< images a second. =es it is far more complicated than this but you really don'tneed know much more. 35mm on the other hand shoots at : frames images6 a second.

=ou may be thinking why does the number of frames>second effect the overall image % surelymore is better? $ell) no. -ot if you want it to look like film. "illions of people across the planetare now accustomed to seeing movies shot at : frames>second and so the motion on screenis embedded in their subconscious. #t is all about the ,feel, of film. 8 different frame rate andthe audience know something is up but they can't say what.

;o the closest you can get to shooting 35mm : frames>second film is &82 5 frames>second.

There are some high%end camcorders that can shoot : frames>second so if you can affordone) buy it % but only if you are intending for your film to one day end up on the big screen.

@. !se 0ilm%2ook ;oftware # saved this one until last as doing all the stuff above

will make a bigger difference than just using this type of software alone.

0ilm%look ;oftware mainly Aagic "ullet) 0ilm0B and 9inelook6 is software that takes yourfootage and tweaks around with the colour) contrast) grain etc. to make it look more like film.9hanging of the image in this way is also known as grading and it can really make your videofootage look much) much better.

0eature movies use grading all the time. Think ,The Aatri1, % a very dark) atmospheric film.Do you think it looked like that on set? "ollocks did it. =eah sure the lighting was done buttweaking the image to make the blacks really black and giving everything a sort of green tint %

that was the work of grading.

=our film%look software works in the same way Aagic "ullet even has a Aatri1 setting6 and soit takes your footage and gives it a desired ,tone,. ;ome of the software can even removedigital artifacts caused by miniDV to help clean the image. 8nd on the polar opposite) you canadd film artifacts like scratching) rolling and dust if you want you video to look like batteredfilm.

http://www.stormforcepictures.com/howto-getthatfilmlook.php

&hotographers set their e1posure using a combination of shutter

speeds and f/stops to get the correct amount of light on the film.

The shutter speed regulates how long the film is e1posed to light

coming through the lens. The f>stop regulates how much light is

allowed through the lens by varying the area of the hole the light

comes through. 0or any given film speed and lighting combination

there is one correct amount of light to properly e1pose the film. This

amount of light can be achieved with many different combinations of





f>stops and shutter speeds. This page goes over the f>stop and

especially its initially%confusing numbering at some length.

The f>stop is a source of confusion and mystery to many

photographers) even to some who use it all the time. # find it

interesting that in the local camera shop they have pictures underglass on the counter showing a scene using a range of focal lengths

for a good e1ample of this) see my friend Dave Dahms' 2ens 0ocal

2ength 9hart6) a bunch of photos showing the same scene printed at

different si*es and a set of photos showing an action scene shot at

different shutter speeds. 8ll that is assumed to be of interest and

comprehension to the customers. $hat they don't have is a set of

photos showing depth of field) or a scene shot at a range of e1posure

combinations where the f>stop's effects are shown. Aaybe it just takes

too much e1planation. $ell) too much e1planation is what this page is

all about.

Fill That Bucket!

Ay favorite analogy for e1posure is filling a bucket of water. 8 bucket

is of fi1ed si*e and needs a certain amount of water to fill it) just like

film) which is of a set film speed and needs a certain amount of light to

capture an image. To fill your bucket) you can pour a small stream of

water for a long time or a fast stream of water for a short time. 4ither

way) you end up with the same amount of water. #n photography) the

si*e of the stream of the water is analagous to the f>stop) the length of

time you pour is analagous to the shutter speed) and the si*e of thebucket is analagous to the film speed. "roadly speaking) from the

bucket's point of view) it doesn't matter which combination of stream

si*e and length of time you choose as long as the right amount of

water ends up coming in. 0ilm is the sameC within limits) it is

indifferent to the combination of time and amount of light as long as

the right amount of light eventually arrives.

Shutter Speeds

;hutter speeds are a bit easier to understand) so #'ll start with those."oth e1posure controls run through a se+uence of settings which

involve doubling and halving the amount of light reaching the film.

;hutter speeds are measured in seconds and fractions of a second and

so the doubling and halving is self%evident. (ne +uarter second is half

as long as one%half second but is twice as long as one%eighth. (ne

second is twice as long as half a second and half as long as seconds.

#t's pretty easy) and this works through the whole se+uence of shutter

http://www.paragon-press.com/lens/lenchart.htm






speeds. (n my -ikon 04) for instance) the shutter speed se+uence is

seconds : seconds seconds second >

second >: > >5 >3< >@< >5 >5< >5<<

><<<4ach of these settings is clearly half>double the length of time of its

immediate neighbours (E) # know) >5 isn't e1actly half the time of

>th and >5th isn't half the time of >@<th) but it's close6. This

doubling>halving is thus pretty simple to comprehend for this e1posure

setting.

F/Stops

f>stops are a bit more confusing because the numbers appear so

arbitrary. This is the standard se+uence of f>stops from f>.: to f>.8lthough it doesn't seem intuitive at first) in this se+uence the f>.:

setting lets in the most light while the f> setting lets in the least.

8lso) each of these f>stops has precisely the same halving>doubling

relationship as the shutter speed se+uence.

.: .< . : 5.@ @

(n the face of it) going from f>: to f>5.@ doesn't sound like halving the

amount of light. $hat's more) 5.@ is a larger number and sounds like it

ought to be more light) not less. -either does f>: to f>. sound like

doubling the amount of light. #n fact) each of the numbers in thisse+uence is a halving>doubling of the amount of light from its

immediate neighbours) just like the shutter speed settings are. -ot

only that) but it makes sense) as # shall show below.

The reason that both the halving and doubling and the smaller

numbers mean more light things make sense is that the f/stop is a

ratio. The ratio is between the diameter of the aperture in the lens

and the focal length of the lens. The focal length is generally

measured in millimeters) so we'll stick with those as our unit of

measure. (n a 5<mm lens) f> is saying that the diameter of theaperture is 5mm. The ratio is this 5<>5 F . 8 good +uestion might

be) what is the area of that aperture? $ell) the aperture is usually a

set of five to fifteen blades which form a roughly circular hole) so we'll

use the formula for the area of a circle) which as you all remember

from fifth grade math is G H radius. 0or G #'ll use 3.:5I@5. (n our

5<mm lens) the aperture at f> has a diameter of 5mm which is a



radius of .5mm. The area of the aperture is thus G B .5 ) or

3.:5I@5 B [email protected]) or :I<.I s+uare millimetres.

This fact by itself isn't all that useful. #t is useful in relation to the

adjacent f>stops. $hat is the area of the aperture at f>.? $ell)

because the f>stop is a ratio of the focal length to diameter) our 5<mmlens at f>. would have a diameter of 5<>. F J.@mm. The area of

the circle thus formed would be G B J.@>6) or 5<.5 s+uare mm.

That's about 5< s+. mm at f>. and 5<< at f>) a double>half

relationship. 8ha7 ;o that's it7 The area of the hole doubles and

halves) it's just represented by a ratio on the lens7 -o wonder it's so

darn confusing.

ere's a table of the aperture areas for the common f>stops for a

5<mm lens

f/stopDiameter of

aperture (mm)Radius of

aperture (mm)

rea of

perture (s"mm)

f>.< 5<.< 5.< )I@3f>.: 35.J J.I )<<

f>.< 5.< .5 :If>. J.I .I 5<

f>: .5 @.3 3

f>5.@ .I :.5 @3f> @.3 3. 3

f> :.5 .3 @f>@ 3. .@

f> .3 . :

8s shownon lens6

5<mm divided byf>stop6

> the diameter6pi B the radius

s+uared6

#f you look down the column of figures on the right) you can see the

more or less6 doubling>halving going on up and down the column. =ou

can see also how the big numbers make for smaller areas since the

f>stop number is being divided into the focal length) then halved) then

s+uared) then multiplied by G. #t's no wonder this seems obscure.

$hy not just call for the aperture area directly? 8 couple of reasons.

0irst of all) if you have a 5<mm lens on and say ,# shot this with my

5<mm at >5th and an aperture area of @3 s+uare millimeters, you

will impart correct and e1act information that precisely *ero people will

understand. #t's way easier to say ,# shot this at >5th at f>5.@,.

8lso) @3 s+uare millimeters is f>5.@ only with a 5<mm lens. #f your lens

is a 35mm) or an 5) or a 3<<) the ratio is changed around and the



e1posure is different. #n fact) that @3 s+. mm is about f>: on the

35mm) f>I.5 on the 5mm and f>3 on the 3<<. Enowing only the area

of the aperture re+uires also knowing the length of the lens also to be

informative as to the amount of light coming through the lens. The

f>stop figure incorporates both of these in one useful if initially

confusing measure and the lens length is immaterial. #t's shorthand) ineffect. $hen you say f>) you mean for this focal length the f?6) give

me an aperture whose area is such that diameter of the resulting circle

goes eight times into my focal length. 0ortunately) the lens makers

figure out all these things for us and just mark the f>stops on the lens

for us. They're doing us a big favor.

#ot it" $hat about other f/stop terms%

$hen people talk about an fast lens& 'hat does that mean%

2enses are referred to by their ma1imum aperture that's the biggest

hole) the smaller number6. Thus) -ikon made at least6 three mm

lenses at one point) a f>.<) a f>. and a f>3.5. 8ll three of

these lenses had f>:) f>5.@) and so on up to f>@C they were

distinguished by the ma1imum amount of light they could let in. The

mm f>3.5) one of which # own) when set to it's ma1imum aperture

of f>3.5) lets in one third less light that the f>.. The f>.) in

turn) at it's ma1imum aperture) lets in only half the light of the

f>.< at it's ma1imum aperture. 2enses which have wide ma1imum

apertures and let in lots of light are called fast lenses. 2enses which let

in comparatively less light at their ma1imum apertures are called slowlenses. The f>.< would be a fast lensC the f>. would be sort of

regular) for which there isn't really a nameC the f>3.5 would be kind

of slow.

$h 'ouldnt ou al'as use a fast lens%

$eight and e1pense. To get those larger diameter apertures means

you need larger pieces of glass mounted in correspondingly larger lens

barrels. They're harder to manufacture) the lens barrel keeps getting

heavier to hold all that heavy glass in alignment so it all gets weightyin a hurry) and they're more challenging optical designs. There have

been very fast lenses made which have the reputation of being really

nice wide open but kind of doggy perfomers stopped down. #f you

normally do not use the fast lens at its widest settings) if you are

mostly at) say) f>) then you are carrying around a heavy and

e1pensive optic which may be underperforming its cheaper brethern

stopped down.



The si*e penalty is really obvious in the long lenses. The weight

balloons and the cost skyrockets. 0or instance) # used to own a -ikon

3<<mm f>:.5 4D%#0 lens. The #0 is internal focus) the 4D had to do

with the 41tra%low Dispersion glass used. #t was a sweet lens) 3<<mm

in length) with silky smooth focusing and weighed in at lbs. .I o*.

IIg6. #f # stepped up to the 3<< f>. lens the weight went to 5 lbs. o* 5<<g6. -ot fast enough? ow about -ikon's 3<< f>? #t weighed

in at 5 lbs. @.I o*. J<<<g6. The 3<< f> picks up >3 stops over the

3<< f>:.5 # owned) but it takes an eminently hand%holdable telephoto

that fits in the camera bag and makes it into an unwieldly unit needing

a tripod) re+uiring its own suitcase and weighing seven times as much.

4ven on shorter lenses the difference is noticeableC my brother%in%

law's -ikon 55 f>. is much heavier than my 5< f>.. is viewfinder

sure is bright and that last stop can be handy sometimes) but the

camera weighs a lot on the neckstrap and you start to +uestion itsvalue if you're shooting at f> anyway. #f you do decide you want the

fastest possible lenses) go buy yourself a 2eica A@ or AJ) for which

you can buy a 5<mm f>.< lens and a J5mm f>.:. 8nd before you

think that it's modern technology that allows these wonders) recall

that 9anon made a 5<mm f><.I5 for their rangefinder cameras back in

the I5<s.

* hear stops referred to a lot" re these al'as f/stops%

-o. 8 source of confusion is that ,stops,) as in f>stops) has become

something of a handy shorthand for other doubling>halvingrelationships when referring to e1posure. Thus) when someone says

they ,stopped down,) they probably did change the aperture from)

say) f> to f>. owever) if someone says they wish they had a stop

more light) they mean they wish they had twice as much. #f they say

they got some 8;8 :<< film which is two stops faster than their ;ensia

##) it means it is four times as sensitive and you can infer that the

;ensia was 8;8 << from :<<) << would be one stop) one halving)

and << would be the second stop) the second halving6. 4ven

e1perienced photographers get confused sometimesC # had one guy

tell me he ,pulled his film @ stops) from 8;8 << to 8;8 @,. $ell)that's not si1 stops) it's four. ere) count along << to 5< is one) 5<

to 5 is two) 5 to is three) to @ is four.

-ote that stops always refer to e1posure things. =ou would not say a

<<mm lens is a ,stop longer, than a 5<mm because it was twice as

long7 =ou would say it was twice as long) or just that it's a <<mm.



$hat is stopping do'n%

#'ve had a number of emails asking about this. $hen you stop down a

lens) you are going to a larger number>smaller aperture and therefore

less light. /oing from f> to f> is stopping down. The opposite is

opening upC going from f> to f> is moving towards the smallernumber>larger aperture and therefore more light.

$hat bout m 'eird f/stops%

The f>stop se+uence # listed is the full stops. Aost things in

photography work in >3 and > stop increments) and you will find

lenses with ma1imum apertures at other%than%full f>stops. #n fact)

among the lenses # own or have owned) there are ma1imum apertures

are f>) f>. and f>:) all right on the full stops) and others in between

at f>.) f>.5) f>3.) f>3.5) f>3. and f>:.5.

+ou Sa ,ost things Double and -alve%

=ep. ;hutter speeds do the >5 >3< >@< >5 thing referred to

earlier. The f>stops we have referred to e1tensively in their

f>. f>: f>5.@ etc. se+uence. 0ilm speeds do the same thing. The

doubling goes like this in the common range of film speeds

5 5< << << :<< <<

4ach step here is a doubling>halving of the film's sensitivity to light.Thus) an 8;8 << film re+uires twice as much light to be correctly

e1posed as an 8;8 << film but only half as much as an 8;8 5< film.

=ou would say it was a stop slower than the <<) a stop faster than

the 5<.

There are third%stop intervals in 8;8s as well. ere are the third stop

increments of 8;8 with the full%stops in bold.

. 3 :< 0 @: < 100 5 @< .00 5< 3< 200

There are still films made at some of the intermediate speeds) like

Eodachrome @: slide film) &lus%B &an &rofessional black and white at

8;8 5) and 0uji -&; and some Eodak &ortra color negative film at

8;8 @<.

-o' do ou refer to e3posures bet'een full f/stops%



*oom lenses might have these6 or you have one lens coated and

another not coated. 8bout the only people who need this level of

precision are professional cinemaphotographers who use the t>stop to

set e1posure. Their lenses sometimes have both f>stop and t>stop

scales marked. 4ven when they know the t>stops of the lens) the

f>stops remain important because depth of field is driven by the f>stopregardless of the light%passing ability of the glass. # have never seen a

still photography lens marked in t>stops) but the concept is out there

so # thought #'d mention it.

The only time # have found the marked f>stop to be undependable was

with a Vivitar @<<mm f> ;eries (ne lens # had. This was a

catadioptric mirror6 lens billed as a ;olid 9at because rather than

mirrors and airspace) it had mirrors with solid glass in between. This

puppy weighed a lot7 8nyway) the lens was f> but my own e1perience

was that if you used a separate meter you'd better think about it as anf> and a half or f> lens.

So $hats *mportant in all this%

=ou need to know the doubling>halving relationship and how it works

with shutter speeds in e1posure. This is key since the shutter speeds

and f>stops you choose have implications in how your final photograph

will look in ways other than purely the amount of light on the film. =ou

need to know that as you stop down you get more depth of field. =ou

do not need to go around calculating aperture areas for your lenses

and f>stops. #f you're like me) it's worth doing it once to see that itworks) then forgetting about.

-o' a Range of Settings #ives the Same mount of 4ight

-ow) to bring this all together) we know that the shutter speeds and

f>stops both double and halve. Thus) we know that we can open up an

f>stop letting in twice the light6 and move the shutter speed one step

faster cutting the time in half6 and have the same amount of light on

the film. 0or instance) if we meter a scene and it tells us that >5th

at f> is the correct e1posure) any of the following combinations wouldwork

;hutter

;peed

>:

second> >5 >3< >@< 1/1. >5< >5<< ><<< ><<< >:<<

f>stop f>:5 f>3 f> f>@ f> f/5 f>5.@ f>: f>. f> f>.:



&ractically speaking) you aren't going to have one lens which takes you

from f>.: to f>:5 and your camera body may not have the higher

shutter speeds. 8lso) if you are without a tripod) there are limits to

how slow your shutter speed can be before your body movements blur

the photo) so there are some constraints. "ut the point remains) all

these combinations yield the same amount of light on the film and anidentical picture in terms of brightness. $hat does vary is the ability of

the camera to stop action and the depth of field) or how much is in

focus in front of and behind the subject. This gives you some control

over how your photographs will turn out. =ou should understand it and

use it.

&; 8fter an e1change with someone who finally understood this after

reading this page which is very flattering # must say6 it occurred to

me that part of the reason this whole se+uence of identical e1posure

combinations is absolutely second%nature to me yet so confusing tonewer photographers is that # started out life metering everything with

a handheld light meter. #nitially this was some long%forgotten ;ekonic

reflected%only selenium meter my Dad had) later IJ@6 the ;ekonic

29 meter) usually in incident mode. The common feature of these

two meters was that they displayed the readings on a dial that showed

every possible combination of shutter speed and f>stop for that

particular light level and film speed. "y the time # moved to modern

cameras and a digital readout meter my ;ekonic 23<"6 the whole

se+uence thing was completely ingrained. -owadays light meters like

my little ;ekonic and many cameras read out with needless and oftenconfusing precision and it appears that there is one correct e1posure)

not a whole se+uence that will give the same e1posure result. -ow)

not everyone gets to use old light meters for a few years to nail down

these relativities) so # did a sheet to help you see all your e1posure

combinations given a reading from your camera or light meter. Take a

look at this sheet and see if it helps.

&&; Thanks to Aike ;heehan of 8urora 9olorado who emailed me with

how to show pi in htmlC ampersand)pound sign)I@<)semi%colon. #

would spell it out like that but it would just show as G.

ave fun with all this7

http://www.uscoles.com/fstop.htm

&laying The 0ield

http://www.uscoles.com/exposures.pdf






The sharpness of the pictures in your footage is oftendependant on how the camcorder is set up. $ith a bit ofpractice) you can use depth of field to your advantage) asTracey ;mith e1plains

Depth of field is something photographers talk about a great deal) and amateur videomakersrarely think about. owever) understanding why parts of your video image are sharp whileother areas remain blurred is a skill which you can use to your advantage. Distracting areas ofyour shot can be made to blur out of focus simply by understanding how the camcorder'saperture works) which will help to concentrate the viewer's attention on the important part ofthe shot. 2ikewise) using a wide depth of field will enable you to cram lots of information intoyour shot without losing anything because it is not in focus.

$ith an ;2K camera the type with a detachable lens) used by professional photographers6)fiddling about with depth of field is easy. $ith some still cameras) there's a depth of fieldpreview) which allows you to see e1actly which parts of the picture will be sharp and whichsoft) before you commit your shot to film. owever) with a video camera) the depth of field isusually set automatically unless you have a manual iris facility which allows some degree of

artistic control. aving said that) there are a few tricks of the trade which are handy to know ifyou want to make your camcorder perform in the best possible way.

!sing a narrow depth of field) parts of the image will always be out offocus. $ith the aperture stopped right down) the only sharp part of thepicture here is the tree) while the window frame outside the depth of

field is blurred$ith this pot of spring flowers right6) a large aperture setting meansthat only a few of the flowers can be in focus at any one time and the

leaves remain blurred

$hat is depth of field?

$hen you focus your camcorder lens) you are adjusting the distance at which images aresharp. ;trictly speaking) depth of field is the distance the subject can be moved throughbefore the image appears blurred. 8nything within the frame that is nearer or further awayfrom the focused distance will appear progressively softer and softer.

0or instance) if you're shooting a football match on a bright day) you'd probably set up yourcamcorder so that the iris was stopped down enough to enable the whole scene to appear



sharp) giving you the ma1imum depth of field or else your camcorder would do this for you ifit was set to automatic6. This would enable you to follow the whole match without continuallyhaving to re%focus as the players move around) and you wouldn't have to worry aboutsubjects darting in and out of focus. owever) say you wanted to concentrate on oneparticular member of the team without changing the focal length using your *oom. =ou coulddo this by increasing the lens aperture opening up the iris6) thereby decreasing the depth offield) which would make the subject stand out. 8nd as the rest of the players behind him

would be further away from the focused distance) they would appear blurred. The same wouldapply if a player ran in front of your subject % he) too) would be out of focus.

The good thing about a wide depth of field is that providing your subject remains within the

set distance) you don't need to continually re%focus your camcorder. The depth of field can bereally wide) or particularly narrow depending on your shooting conditions.

The way in which depth of field works within a camcorder is that when you focus your image)points on the plane of sharp focus are focused as points of light on the camcorder's 99D.8reas of the image that don't appear on this focal plane are resolved as ever increasing largecircles on the chip depending on their distance away from it. These points will then appearblurred. The depth of field) then) is the distance through which the subject e1tends and stillforms a suitably sharp image. !sually) there is a greater depth of field beyond the plane of

sharp focus than in front of it.

The depth of field within your shot varies depending on three main things the distance atwhich the lens is focused the closer the focussed subject to the lens) the less depth of fieldyou will have6) the lens aperture the si*e of the iris6 and the lens angle in other words) thefocal length % the more wide angle the lens) the greater the depth of field6. Eeeping theaperture and focal length the same) the depth of field will increase as the camcorder movesfurther away from the subject. owever) the si*e of your subject will also decreaseproportionally. This also happens when you adjust the lens focal length ie) *ooming in willincrease the si*e of your subject6) but by adjusting the aperture) you can keep the si*e of yoursubject constant) and only affect the background or foreground. 0or e1ample) if you wanted toshoot a se+uence involving different coloured flowers against bright green foliage) you wouldprobably want to use a wide aperture giving a narrow depth of field6 to keep the flowers bigand bright in the frame) while allowing the green background to blur. This would help to make

the flowers stand out without the background competing for the viewer's attention.



$ith street scenes) such as this preparation for acarnival) you want as much of the image as possible tobe in focus as much of the action is happening in the

background

!sing a medium iris setting) most of the foreground issharp and the trees in the background are clear. (nly

the parts of the fence nearest the viewer are not withinthe critical point of focus

Enock%on effects

8s we've already seen) by decreasing the depth of field using the aperture) the camcorder'siris is opened up a few stops) so more light will enter the lens. (ne important knock%on effectthat this will have on the video) is that the camcorder's shutter speed will increase slightly inorder to decrease the amount of light reaching the 99D) otherwise the resulting footage could

be too light. owever) this could become a little tricky) especially if you're shooting fast actionsuch as someone running) as the movement will then become jerky. 0ast shutter speeds areusually reserved for when you want to analyse a fast action) such as a golf swing) step%by%step. =ou can pause the video and advance it frame by frame to view each individualmovement) but when the video is replayed at normal speed) it will appear as if there are blackflashes on the tape. Therefore) using a high shutter speed is generally only useful if yoursubject is either stationary or moving slowly.

There are ways around having to use a high shutter speed. 8s we e1plained earlier) movingthe camcorder nearer the subject will help to throw the background out of focus) especially ifthey are standing as far away as possible from the objects behind them. 8lso) using thetelephoto setting on your lens will cause the background to blur. The effect will be morenoticeable the further you are away from your subject. (bviously) if you are shooting in asmall room) there will be a limit as to how much you can *oom in without cutting your

subject's face in half % try moving away as much as you can first.

8lso try decreasing the amount of light in the scene. #f you're shooting indoors) this might

involve closing the curtains or switching off one of the lights) or else re%positioning yoursubject so that less light hits them. owever) you have to make sure that they are brightlyenough lit so that the viewer can see what you're shooting. 8nother good trick is to fool yourcamcorder's e1posure system by fitting a neutral density filter onto your camcorder lens)which will work to restrict the amount of light reaching the 99D. The camcorder will naturallyopen up its iris) causing the depth of field to be greater. 8lternatively) you could always try a



polarising filter) which will cut out some light if it is rotated correctly so it has the strongesteffect.

;hooting this football match is fairly straightforward using a narrow aperture to give the ma1imum points of focus in thescene. owever) to pick out one of the players) it's better to open up the iris and reduce the depth of field below6

#n some situations) though) you might want as much of the scene as possible to be in sharpfocus. 0or e1ample) if you're filming a street carnival) you'd want to be able to see the peoplewalking towards you as well as those following on behind. ere) you'd need to make sure thatyou use a wide focal length) increase the distance between yourself and the scene you'reshooting and make sure you have the camcorder set to manual or a standard mode % nothigh%speed shutter. 8lso) it's beneficial to increase the amount of light in the scene to forcethe iris to close down even more) giving you a wider depth of field.

D4&T (0 0#42D 4B&28#-4D

9ertain program auto e1posure modes on camcorders automatically adjust the iris value)although you might not realise it. 0or instance) a camcorder's &ortrait mode works bywidening the aperture and throwing the background out of focus) restricting the depth of fieldso that the view can concentrate on the subject or portrait in the frame. #t also helps byblurring any potentially distracting background movement. This) however) might be theopposite of the effect you're looking for in certain situations % for instance) it might also bebeneficial to show the viewer what's going on behind your subject.

2ow%light modes also adjust the iris to allow more light in) although on some camcorders) thismay be coupled with electronic boosting to brighten the image. ;ports and igh%speed shuttermodes also adjust the si*e of the iris and hence depth of field6 to compensate for the higher

shutter speeds they employ. (ften) however) these need to be used in areas of good or brightlight) to ensure correct e1posure.



Testing out depth of field

;tep . &osition your camcorder andtripod fairly level with the table) and

focus on the wine glass. #f yourcamcorder has the facility) choose a

wide iris setting) and watch how thewine glass becomes the point of focus)throwing the background into a blur

;tep . 41periment by changing the irissetting. "y narrowing the aperture andfocusing on the bottle of wine) the wine

glass and cork are blurred) yet thebackground becomes much sharper

;tep 3.;et the aperture to a mid%pointbetween the previous two values. erewe find that the cork lying on the tablehas become the point of focus) yet both

the glass and wine bottle are bothmuch sharper than before

http://www.whatcamcorder.net/articles/practicals/200202/200202.php

Lens Focal Length

What is Focal Length, anyway





!ery simply, it is the distance from the lens to the film, when focused on a su"#ect at

infinity. $n other words, focal length e%uals image distance for a far su"#ect. &o focus on

something closer than infinity, the lens is mo'ed farther away from the film. &his is whymost lenses get longer when you turn the focusing ring. &he distances follow this

formula:

&his means a (00mm lens should "e (00mm long. $f you get out your ruler and measureit, you will find it is less than (00mm. &hat is "ecause a camera lens really has many

indi'idual glass lenses inside, and this makes it "eha'e as if it is longer than it really is.

&his is called )telephoto.)

What is F-*top, anyway

F-stop is the focal length di'ided "y the diameter of the lens. For e+ample, a 200mm f/(lens will "e 0mm wide. et out your ruler and measure it. 200mm/0mm f/(. &hat is

why f-stop is typically written as F/4, meaning )focal-length o'er () or )focal-length

di'ided "y four).

Where do those num"ers come fromLenses are marked with a series of f-stops, each one lets in half as much light as the

pre'ious one. &he light-gathering a"ility of a lens is determined "y its area, and f-stops

are determined "y diameter. rea is related to diameter s%uared. &he progression of f-

stops, - .( - 2 - 2.1 - ( - . - 1 - - - 22 - 32, are powers of the s%uare root of 2.

For a further e+planation of f-stops, try this.

Lens Focal Length 4hart

&aking the nature photographs like those in my "ooks a"out 5ocky6ountain 7ational 8ark, Wildflowers and Wildlife re%uire an assortment

of lenses depending on the su"#ect. &ypically normal to wide angle lenses





are used for landscape photos and 'ery long telephotos are used for

wildlife. &he photographs "elow show the 'iews of a single scene taken

using these lenses.

&hese eight photos were taken from the same place with different lenses.

&he su"#ect is Longs 8eak from 9pper ea'er 6eadows in 5ocky6ountain 7ational 8ark.

2(

mm

3m

m

0

mm

00

mm

200mm

(00mm

100

mm

200

mm

"I want to take a bluebird picture. What lens

should I use?" $t is a symptom of "ird



photography that your lenses ne'er seem to "e long enough. &his is "ecause "irds are so

small. When photographing large animals, a (00mm gi'es you decent image si;e from a

reasona"le distance. ut remem"er, an elk is si+ or se'en feet tall. "ird is "arely si+

inches long, so when your su"#ect is twel'e times smaller, you ha'e to "e twel'e times

closer.

s you can see, e'en a

relati'ely huge 00mm

lens at the relati'ely

close distance of 20 feet

doesn<t gi'e the huge

magnification you might

e+pect. &he field of 'iew

is a"out twel'e inches. $t

takes a "ig lens to photograph a small "ird.

=ome

http://www.paragon-

press.com/lens/lenchart.htm

,atts -and 6hoto #uide 77 The

Technical Stuff 9ole's ome &age The 8rtistic ;tuff

This is a +uick and dirty reference piece to your camera's controls and

the ways in which they affect the photographs you take. There are two

controls which affect the e1posureC the f>stop or aperture6 and the

shutter speed.

Shutter speeds are indicated on your camera in fractions of a

second) that is) ) 5) 3< meaning >th) >5th and >3<th of a

second. 9ameras commonly go up to ><<<th of a second and somego to >:<<<th and even ><<<th. 8lthough) say) >3<th of a second

sounds just bla*ing fast) it is comparatively slow for a camera and is

probably as slow as you can hand hold the camera with your normal

lens.

The crucial thing to recogni*e on shutter speeds is that each setting is

half as long and twice as long as the adjacent speeds. That is) if your

http://www.paragon-press.com/index.htm



http://www.uscoles.com/index.htm

http://www.uscoles.com/artistic.html

http://www.paragon-press.com/index.htm




http://www.uscoles.com/index.htm

http://www.uscoles.com/artistic.html



camera is set at >5th of a second) moving the shutter speed to

>@<th opens the shutter and therefore e1poses the film6 for twice as

long) whereas moving it to >5<th of a second e1poses the film for

half as long. The whole se+uence does that%%doubling and halving as

you move up and down the dial.

-ote ere's the se+uence of standard shutter speeds) starting at

full second. Kemember) each of these is twice>half as long as the

adjacent shutter speeds

second > >: > >5 >3< >@< >5 >5< >

5<< ><<< ><<<

Aany cameras have manual or automatic shutter times slower than

secondC a few cameras have speeds faster than ><<<th. The to><<<th range is pretty universal although most leaf%shutter cameras

don't ask6 stop at >5<<th. 8lso note that many modern automatic

cameras will have digital displays showing intermediate speeds) e.g.)

>35<th) >J<<th) etc. Don't get confused. The same rules apply%%

>35<th is clearly twice as long as >J<<th) but is also somewhere in

between >5<th and >5<<th.

0rom an artistic point of view) the shutter speed you set controls your

ability to stop motion. Very fast shutter shpeeds ><<<th) ><<<th)

etc.6 can ,free*e, very fast action) such as a football kickoff or child on

a swing. ;low speeds >th) seconds6 have less ability to stop

motion. This isn't all bad%%think of a waterfall where an e1posure at

>: of a second invariably gives a more pleasing result than >5<<th

but use your tripod76.

The f/stop) or aperture) is the control which regulates the si*e of the

opeing in the lens through which the light passes. The small numbers

f>.:) .6 are large apertures) and let in loads of light. The large

numbers f>) f>@6 are small holes) and let in much less light. Lust

like on shutter speeds) each f>stop lets in half as much or twice as

much light as the adjacent stops. Thus) moving from f> to f>5.@smaller number) larger hole6 lets in twice as much light) whereas

moving from f> to f> larger number) smaller hole6 lets in half as

much light. 8lthough it isn't as obvious from the numbers) the f>stops

have e1actly the same sort of doubling>halving relationship as shutter

speeds have to each other. To see this e1plained further) take a look

at 8 Tedious 41planation of the f>stop to see if it clears things up a bit6





-ote ;ince f>stops can be confusing) here's the se+uence of full

f>stops. Kemember) each of these lets in twice as much>half as much

light as the adjacent numbers

f>.< .: .< . :.< 5.@ @ 3

2enses as fast as f>.< are e1tremely rare) rare enough that #'ve never

seen one in personC not many lenses for 35mm stop down as far as

f>3. -ote that in the lingo) going from a wide aperture small

number6 to a small aperture larger number6 and therefore letting in

less light is known as ,stopping down,. /oing the other way) and

letting in more light) is ,opening up,.

0rom an artistic point of view) f>stops affect how much will be in focus

in front of and behind the subject on which you actually focus. This is

called depth of field. $hen the lens is set to a large f>stop say) f>.6)relatively less will be in focus in front of and behind you subject. There

are times when you want to have absolutely everything in sharp focusC

a small f>stop large number6 is needed for this. (ther times) you'll

find that throwing everything but the subject out of focus is a very

good way of isolating your subjectC in this case) you'll need a large

f>stop small number6. 0inally) there will be other times when you are

fairly indifferent as to the depth of field) and in these cases) # usually

use f> or f>) which are the f>stops where lenses are usually their

sharpest.

-ow) lets tie it together. 0or any given amount of light and film

speed) there is one correct amount of light for a correct e1posure but

this amount of light can be achieved with a whole series of correct

e1posures. This is because both the shutter speeds and f>stops double

and halve. #f the camera gives you an e1posure of >5th at f>) you

can get the same amount of light to the film by setting the camera to

>5<th at f>5.@ twice the light for half the time6 or >@<th at f>

half the light for twice the time6 or >3<th at f>@ one +uarter the

light for four times as long6) and so on. #n each case) the amount of

light on the film is identicalC what changes is your depth of field and

your ability to stop motion. This gives you creative control over how

your pictures will turn out. !se it. # have posted a handy page here to

help make these relationships clearer. Take a look at this if this still

seems confusing6.

8nd dont get bogged do'n in the trivia. The stuff up above) once

learned) is the foundation for understanding the rest of photography.





#t's simple for enthusiastic amateurs and e+uipment freaks to go off on

debates about different camera brands or tripod +uick release systems

and try to impress you with their knowledge of filter factors. Aost of it

is trivia at this point. #t is true that wide angle lenses have greater

depth of field than telephotos) but the general rule that a smaller

f>stop gives greater depth of field still applies. #t is true that longerlenses re+uire a higher shutter speed to be held steady) but the

general rule still applies that a faster shutter speed has a greater

ability to stop motion. #t is true that films behave differently at very

short and very long e1posure times) but you probably won't be

operating in those regions until you are at a point where you'll be

ready to read about reciprocity failure and how to adjust for it. $hat

you need to understand is above) and further knowledge will flow

naturally from that and from taking and criti+uing lots of pictures. ;o

get out there and start shooting7

http://www.uscoles.com/technical.html

http://www.whatcamcorder.net/articles/





Camera Fundas

Documents

Transcript of Camera Fundas