Photo 10: Intro to Photography

Everything I know about Metering

So What is Metering? Metering is the best way to really understanding exposure as a creative tool. It can be easy to think of the meter as being able to just spit out the correct settings for you to imput. I think this is a mistake. Its more useful to think of it as an exposure tool. All the meter can really do is measure the light it cant tell you what the correct exposure is. One of the really great things about taking an analogue photography class is the fact that it forces you to learn to use the camera in its most basic form. You will make tons of mistakes of course after over of decade of film photography i still make exposure mistaks. As a beginner often times you just want to get out there and take pictures buts its going to be things like your exposure that really begin to shape your aesthtic as a photographer.

DONT GET BOGGED DOWN. allow yourself to take a meter reading and adjust intuitvly.I know this is scary with expensive film that you cant see. To be honest the film has alot of lattitude and its more important to meter correctly than to meter often. This is also true of focusing. One of my biggest regrets when learning photography starting out was allowing myself to get bogged down with worrying about what the meter was saying. So much of photography is learning to trust your own insticts. The idea is to get familiar enough with metering to make decisions comfortably and confidently. I can’t tell you how important this is. Photography is subject driven. its important to engage with your subject regardless of what the meter is doing or saying. Getting the photo is more important than the photograph sometimes. Do your best to not overthink it. When you get your film back you will learn from the mistakes. This is the natura way and its really the beauty of shooting film. Honestly when i learned to just trust my intuition when metering i started to have much more consistent exposure. You measure the light with your meter then you make decisions about exposure with your eyes. take your meter reading. and then ask yourself has the light changed? has the subject moved in the photo. have the clouds moved. you can tell theses things pretty easily. if the light hasnt changed there is no reason to re-measure the light.

How is Photographic light Measured?

Light is measured in stops. In photography everything revolves around light stops. you will also commonly see stops of light reffered too as EVs. these two terms are interchangable. the term stop cam from the indentations of the various settings on a camera. For example on a lens you will often feel clicks between the number. some lenses will have steps inbetween the larger clicks in equaly increments to ensure consitency. most lesns and shutter speed dials have indentations of full stops and sometimes 1/3 or 1/2 stops between. 1 stop= 1 EV. exposure value increases and decreases logarithmically. what this means is that each stop of light is double the amount of light as the previous. mathmaticall its written this way

What is an F-stop?

on your photographic lenses you will see these ev values written as f-stops. or apeture stops. usually starting around f1.4 all the way up to f64. these depend largely on the lens and the format. larger format lenses will have smaller f-stops and smaller formats will have small formats. remember. these stops increase and decrease logarithmically. f1.4 is twice as much exposure as f2.o which is twice as much light as f2.8. and so on and so on. So as the lens opens up you expose the negative to more light. this is usually refered too as opening up. and as the lens is closed down you are exposing the negative to less light. This is usually reffered too as stopping down.

What is a shutter speed?

first we have to discuss shutters. their are typically two types of shutters. their are focal plane shutters and leaf shutters. you will typically find leaf shutters on medium and large format cameras but sometimes you will find them on 35mm cameras. to put it simply leave shutters are in the lens and focal plan shutters are in the body of the camera. 35mm slr cameras typically have focal plane shutters. These are the most common cameras for beginers. on these cameras you will see the shutter speeds written on a dial on the lens. The range of shutter speeds will depend on the camera. most of your analogue cameras will top out between 500 or 1000th of a second. and they will go down to 1 second. These shutter speeds are fractional. they arent always written that way depending on the design but they always correspond to fractions of a second. These shutter speeds are also conviently seperated by stops or EVs of light. they go from 1, 1/2, 1/4 , 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, 1/500, 1/1000. there are also somtimes settings of 2 or 4 or 8 seconds. and usually always a bulb setting. the bulp setting leaves the shutter open for as long as you hold it down and it allows you to make exposures as long as you need too. these settings also increase and decrease logarithmicly. 1 is twice as much as 1/4 with is twice as much as 1/8 which is twice as much as 1/15. these “stops” corespond conviently with the stops on the lens. this allows you to couple these stops and change them in eaqual amounts to get precise exposure.

What is ISO?

Iso is typically your only static setting. Iso correspods to the sensitivity of the film? all films have a native iso. The iso is the sensitivity setting that the film is best shot at inorder to give the maximum amount of dynamic range. in analogue photography you can change the iso as a setting but you actually arent changing exposure you are simply changing the way the meter works to possibly compensate later in processing or to simply change what your looking for in terms of correct exposure. Remember iso is always static. Iso does not change exposure it only changes the way the meter responds. only shutterspeed and fstop effect exposure. iso is static.

isos are specified in the specs of a film stock. they are usually written in full stops but sometimes they fall in between. for example. 100, 200, 400, 800, 1600, 3200. each one of these corespond to EVs or stops of light. changing your iso setting on the camera is the simplist form of exposure compensation. This typically refered to as pushing and pulling film. you can request for a push or pull from the lab you are processing your film. pulling film involves overexposure inorder to gain access to wider fstops or slower shutterspeeds. pulling film also trades contrast and possibly highlight detail for this. Pushing film does the opposite. pushing film involves underexposure to gain access to smaller fstops and faster shutterspeeds. pushing film trades shadow detail and resolution for these chages.

You can think of the photographic film as being a bucket of information that slides along a scale from dark to light. your can slide that bucket towards the highlights or toward the shadows depending on how and where you meter. pushing and pulling typically involves chemical compensaiton for changes in exposure. so rather than moving that bucket from towards the shadows or towards the highlights you keep it where it is stretching it or compressing it. digital histograms represent this well. pushing the film compresses that information and pulling the film spreads it out. inorder to fit in the same bucket pushing the film involves throwing away information in the middles tones this is why pushing the film simultaneously decreases the resolution and increases the contrast. pulling the film reduces the contrast while maintaining the resolution.

Types of meters

There are two basic types of meters reflective meters and incident meters.

Reflective meters:

Reflective meters measure the light that is bouncig off the subject back into the camera. images are made up typically in these two ways reflected light and incident light. Reflective meters are the meters found in your camera. so we have to pay special attention to them. reflective meters use the tonality of what you point them at and then use a reference value to give you a series of camera settings. these are the EV values i talked about. although these values may not be the exposure were looking for we can use them to measure the light and make decisions later about exposure. The reference tone that reflective meters usually use is 18 percent grey. . we call that neutral grey. a reflective meter is always trying to reproduce this 18 perecent grey when it takes its measurment. you have to keep this in mind when your photographing. when you average out the tones of many photographs then you end up with grey. But of course photographs arent grey. as an image makers you want to aspire to make images with rich dynamic tones. you cant do that if you settle for 18 percent grey. its a good starting point but you have to move past it. For example if im trying to photograph something black with a reflective meter it will give me the settings to produce a grey image. and if i try to photograph something white it will do the same it will give me the settings to produce something grey. but whats useful is the fact that those settings will be differnt and i can use the differnces to figure out what the correct exposure is. this strategy is known as the zone stystem and it is one of the foundations of photographic metering.

What is the zone system?

The zone system was invented by Landscape Photographer Ansel adams. The zone system is a way of using a refletive spot meter to place tones along a scale in a photograph depending on where we find neutral grey. The zone system also involved making adjustments for out of range elements with manipulation in processing. the zone system essentiall involves taking meter reading of the most important part of a scene with a reflective meter then placing the tones along a scale of reproducable tones and using processing manipulation to fill in what the film struggles to produce. this typically involves exposing for the shadows and processing for the highlights. you cant always making adjustments for individual images in processing for your pictures. when shooting roll film we have to make decisions about the general tones we are willing to focus on and the ones we are willing to compramise. this is what i mean when i say moving the bucket of information around. with roll film you can manipulate the processing on a roll by roll basis but you can still manipulate exposure with every image. the zone system can s be a really useful tool for understanding how to do this. Ok so you can think of the zone system as a gradient of tones with zones from zone 0 all the way to 10 1 being the lightest and 10 being the darkest. we really only have to worry about zones 2 through 9. these zones conviently are also seperated by EVs . the zone system is the key to understanding how to properly use a reflective meter. A reflective meter is always trying to reproduce 18% grey on the zone system that means zone 5. if i know where are all my other tones lie along the zone sytesm i can make adjustments by the same amount of diffence in zones as stops of light on the light. meter. if youve watched my video you can see how this works.

Incident Meters:

Rather than measuring the intensity of light reflected off the subject an incident meter measures the light falling on the subject. Incident meters don’t care about the tonality of the subject they are simply measuring the light independent of the subject. Incident light meters are typically handheld for this reason. they are measuring the light the subject is in and in order to do that you have to be in the same lighting conditions. generally the closer you are to your subject when measuring the more accurate your meter reading. these meters are by their very nature more accurate because they are measuring the light directly. if you can calibrate your film to the best iso best represents your film stock you can meter very precisly. these meters can be used both in the studio and outdoor. as long as the light your in isnt falling off or ubstructed by shadows for example your metering will be consistent. remember an incident meter must meauree the light that is in the same lighting conditions as what your photographing. the differnce between incident metering is best understood as meter from the front or inside of the camera or from behind it. the reflective meter is looking at the subject and metering and an incident meter is metering the subject at the source where it is.

PROS and CONS

Incident vs reflective pros and cons.

the benefit of a reflective meter is it allows your to meter both visually and compositionally through the camera. the issue is it can be misleading because it is trying to reproduce 18% grey. in difficult lighting conditions and for beginners they can be misleading.

The benefit of a incident meter is accuracy. an incident meter doesn’t care about the tone of what the subject is. it meters the intensity of light in a literal way. the con is that you need to be in the same lighting conditions. you need proximity to be accurate.