with Lorelle and Brent VanFossen

Basic Nature Photography Chapter 4 – The Camera Body

Camera bodies were originally made from metals, typically aluminum. Today’s cameras have hard plastic bodies and will actually take a lot of abuse. Most modern cameras have a molded hand grip which often stores the batteries. This allows for a more comfortable grip on the camera.

front of the Canon A2 cameraIn the class, we refer to the “ideal” camera as a 35mm SLR camera. SLR means single lens reflex. Old box cameras and rangefinder cameras, and most new point-and-shoot and digital cameras have a viewfinder separate from the view through the lens. In the viewfinder are etched boxes to show the photographer the outline of the view of the lens. SLR cameras have a prism and mirror inside the camera which direct the actual view through the lens to the eye. What you see is a fairly accurate representation of what the film will see. You see what the lens sees.

Another characteristic of the SLR cameras is that they allow for interchangeable lenses in a variety of lens lengths and speeds. Only a few of the new point-and-shoot and digital cameras offer this option, replacing interchangeable lenses with long zoom lenses. This flexibility increases the photographer’s creative options.

The name “35mm” refers to the width of the film the camera takes. This is the most common film format used today. You can use the same film in a point-and-shoot camera as you do in a 35mm SLR professional camera. Digital cameras typically imitate this same size format. Other film and camera sizes include 120 or 2 1/4, 4 x 5, 6 x 7, 8 x 10 and a variety of others. Film sizes, gone the way of the pop top soda can, were 110, 126 and 8mm. Tomorrow, 35mm may even disappear in exchange for the next film fad or digital memory.

The Viewfinder Challenge

Example of how a small detail, like the sky peeking into the frame, can be missed with less than 100% viewfinder
Pay attention to the details NOT in your viewfinder. Most viewrfinders see less than the film records so you have to “see” what isn’t in the viewfinder that may show up on your photograph. In this photograph of the hills of the Painted Hills in Oregon, the sky sneaked into our composition in the upper left corner, not seen in the viewfinder.

Camera manufacturers have designed most camera bodies with less than a 100% viewfinder – a common coverage is about 92%. When you look through the viewfinder, you only see 92% of what will actually show up in your slide or negative. You carefully compose to eliminate that piece of sky from the corner of the picture, only to have it show up when your film comes back. And you swear that you looked around the entire frame before firing the shutter.

Why would a camera be designed like that? The main reason seems to be cost. It is technically difficult, and therefore expensive, to make a pentaprism which will show 100% of the image. And the resulting viewfinder image would be smaller and harder to see. The cameras which have 100% viewfinders are the professional models like the Nikon F5, F4, and the Canon EOS 1 series. These cameras also have what is called a “high-eye point” viewfinder, which allows a larger viewfinder image. In a very price-competitive market, few cameras have these features.

The other reason, the manufacturers tell USA, is that automatic print machines crop our pictures some when they print them. And slide mounts cover a part of the image. So the 92%, or whatever percentage your model has, is the manufacturer’s approximation so that what you get back from the photo-finisher matches what you saw when you took the picture.

Test image of grid paper reveals what is really photographed compared to what is seenthrough the viewfinderUnfortunately, we find that the approximation is not very accurate for us, and we have to zoom out slightly to check the edges for intruders before exposing our film. We recommend that if you can afford them, 100% viewfinders make tight compositions 100% easier.

To check your “view” in your camera’s viewfinder, with your camera on a tripod, photograph a piece of graph paper. Mark on the paper where you see the corners in your viewfinder. Get the film processed and compare the results. As you can see in our example, the corner marks are quite a bit indented from the actual film edge. With this information we can take more care in composing our images to account for this unseen space.

Outside the Camera Body

Back dials of the Canon EOS A2A camera purchased new today is a state-of-the-art computer, not just a glorified picture taker. In fact, the technical aspect of taking an actual photograph is the easiest thing the camera does. A computer isn’t even needed to accomplish that. Figuring out how to take the picture can require very sophisticated computer engineering. Nowadays, cameras beep, blink, flash, pop and whir and click at you. Some even talk to you: “There is not enough light to make a proper exposure.” It’s a little scary.

Whether you have a newfangled computerized camera or an old manual everything, or even a point-and-shoot camera, the basic functions are all the same. Let’s look at the outside of the camera first, then we will explore the inside.

What do all the buttons do?

A 35mm camera can be overwhelming when you stop and look at all the buttons and dials. They may spin, whirl, slide or twist, but they all do the same things. Camera manufacturers are always working to move things around on the camera so the fingers will have access to the appropriate buttons. Unfortunately, this doesn’t always happen, and so the camera designers redesign and redesign and confuse the heck out of camera buyers. Just remember this: even though it may look different, the buttons all do the same things.

The off and on buttons all look different on different cameras. Some cameras have a switch which slides, twists or swings. Some older cameras turn on their meters (that means the camera is on and power is draining from the battery) when the film advance lever is pulled out. Some cameras require two moves instead of one to turn it on; push in and turn at the same time.
The Battery Storage Area
Do you know how to change your camera’s batteries? Newer cameras need battery changes more frequently than some of the older cameras as today’s cameras require more power. Older cameras may take one to five years between battery replacements, so we tend to forget where the battery goes. If you will be storing your camera, you might want to think about removing the battery first. Always carry extra batteries. And then extra extras. This you will hear a lot from us. We know well the agony of photographing a prize animal only to have the camera go dead as the animal is posing perfectly. By the time you replace the battery, the moment may be gone.
Program Buttons
Program dial of the Canon EOS A2Most cameras come with a variety of program selections. They are often marked with a letter of the alphabet and you are supposed to understand what it means. Here is a brief list. For more specific information, look in your manual.
Program mode
In this mode, the camera will automatically set the shutter and aperture for the appropriate average exposure. It does all the thinking for you.
Manual mode
This is when you become the brains of the camera. Manual mode means the camera’s meter will tell you when it thinks the exposure is correct, but you have to choose both the aperture and the shutter speed.
A or Av Aperture Priority
Similar to Program mode, you choose the aperture and the camera will match it with an appropriate shutter speed. This is good for determining the correct depth of field and letting the camera choose the rest.
Auto or Aperture
In older cameras, this may mean Auto, which is the same as Program mode. In other cameras, it could mean Aperture.
S or Tv Shutter Priority
Similar to Aperture Priority, you choose the shutter speed and the camera will choose an appropriate aperture. This is good for moving subjects, allowing you to choose the speed you wish to “stop” them at. Tv means “time value”.
XFlash mode
This sets the shutter speed to the maximum speed the camera is capable of using while still synchronizing with a flash. In X mode, the shutter is locked to the flash speed and you may adjust the aperture to the desired depth of field.
In this mode, you have manual control over the shutter. It will stay open as long as you hold your finger down on the shutter button. You must still set the aperture to the desired setting, but this allows you to keep the shutter open for long periods of time. It is a fun creative tool especially for night photography or long, low light exposures.

Some new cameras also feature picture symbols on one of the dials: mountains, a person running, a flower and others. These are program choices which will take into account what your subject is. If you want the maximum depth of field and are doing a scenic or landscape of a field with mountains in behind, you might choose the symbol of the mountain for scenic photography. The running person symbol tells the camera to photograph the subject at the highest speed possible to stop the motion. A flower usually means you will be photographing close up and require closer focusing ranges and maximum depth of field. Check your manual to find out the specific meaning of each symbol.

Shutter Release
The shutter release is usually found on the right side of the camera (there are lefty cameras available but rare) right where you would put your finger. When pressed, it may do several things: turn on the meter, activate the autofocus, and take the picture. Autofocus and the meter are activated when you press the shutter release about half way down. Press further and it will take a picture. A few new, beginning level cameras have a protective feature that permits you to press hard once to autofocus and check the meter and requires a second push to take the picture. Some autofocus cameras will not allow you to take a picture unless the image is in focus, too. Read your manual to determine how to use the shutter release and practice pressing the shutter release when there is no film in the camera. If your shutter release button has a hole in the center of it, that connects to a shutter release cable connects there.
Speed Dial
expspeeddial2.jpgThis is the dial, switch or control which adjusts the speed of the shutter inside the camera. When the camera is in manual mode, you have control over the speed. The speed or shutter dial tells the camera to open and close the shutter at the set speed. It controls the time light comes into the camera and exposes the film. We will discuss its purpose more in the Exposure section. Each camera model has the speed dial or shutter control in a different location. Some cameras feature the dial on top of the body, while others use one switch to control both aperture and shutter, but you press a different button somewhere else on the camera to choose which one you want to adjust. Read your manual to find out how this works.
Aperture Dial
The Aperture Dial or Aperture Control button selects the aperture of the camera. Consult your manual for the specific location and action to initiate this button or dial. It may be a button on the camera body or it may be the ring around the lens close to the body of the camera. The aperture of the lens controls the amount of light coming into the camera and affects the exposure of the film to light as well as the depth of field in your image.
Depth of Field Preview Button
This is another feature which does not exist on many newer cameras. The depth of field preview button closes the lens aperture to the selected f -stop so that you can preview the depth of field before taking the photo. For those who don’t recognize the name, this is the button that makes everything in the viewfinder get darker. The depth of field preview button is useful so you can see if you have chosen an aperture which will hold the subject sharp, while controlling how out of focus the background is. By closing the aperture to the chosen f-stop, the image seen in the viewfinder gets darker, and it may be hard to really see what is there. With a little practice, however, you can see enough to help you in your aperture choice. The final photo will look normally bright, because you are compensating for a smaller aperture with a longer shutter speed.
Mirror Lock-up Button
When pressed, this button manually lifts the mirror inside the camera. This is useful for minimizing camera shake, which can cause out-of-focus images during high magnification photography.
Autofocus/Manual Focus Button
On most autofocus cameras, there will be a button either on the camera or on the lens which turns the autofocus feature on and off. For those times when autofocus is inconvenient, this is a nice feature.
ISO/ASA Button or Dial
The ISO is the abbreviation for the International Standards Organization. In the “old days”, this was called the ASA or American Standards Association. The numbers indicate the sensitivity of a film to light, and the higher the ISO, the more sensitive the film. For example, 200 speed film is twice as sensitive as 100 speed film and requires a faster shutter speed or smaller aperture. And 400 speed film would be twice as fast as 200. The ISO control tells the camera which speed film is in the camera. In modern cameras, there is a sensor which reads the coding on the side of the film canister, called “Dx”, and relays this information to the camera. The ISO control overrides that setting.
Lens Release Button
To remove the lens from the body on most newer cameras, press in this button and twist the lens to unlatch it. On some older cameras, the lens is literally unscrewed from the body. If you are having problems focusing with autofocus cameras and lenses, check to make sure the lens is tightly fastened to the camera body.
Exposure Lock Button
Press this button to “freeze” the exposure setting on the meter. This is useful if your composition places the neutral-toned object away from the metering points. Meter the subject, lock the exposure and recompose, and take the picture.
Manual Advance Lever
Most newer cameras automatically advance the film after the exposure is finished. Older cameras have a manual advance lever located near the thumb when the finger is on the shutter release. Pulling this out turns on the meter. Ratcheting this out and to the right advances the film and readies the camera for the next shot.
Manual or Power Rewind Button
Found in various places on different cameras, these allow for rewinding your film in the middle of the roll.
Exposure Compensation Wheel or Button
This tells the camera to over- or under-expose the film by a specified amount, usually up to 2 stops plus or minus.
Self Timer
This button will set the camera to take a picture 2 to 20 seconds after you press the shutter. This is the feature you use to put yourself in the photograph. It’s also useful if you have forgotten or lost the cable release.
Fancy Buttons
Cameras with a lot of bells and whistles have assorted buttons which allow you to do fun things. You can print the date on your film, turn the beep on or off, take multiple exposures, change the options, rewind the film, and control the bracketing capabilities.

More Things on the Outside of the Camera Body

Camera designers and manufacturers put all kinds of fancy buttons, LCD readout screens, mini TV screens, and lots of windows and gadgets onto the outside of the camera body. Here are a few of the traditional elements:

Film Counter
explcdtop.jpgEither seen as a counter through a small window, usually by the shutter release, or as an LCD readout, this information tells you how many pictures you have taken. Occasionally, it can be set to show how many pictures are left.
Film Window
Most cameras made since the 1980’s feature a window in the back of the camera for viewing the film canister. In that window, film manufacturers have placed the specific information regarding the film’s speed, number of exposures and brand. Older cameras had a holder on the back of the camera which held a torn off top of a film box in place to remind you what kind of film you had in the camera.
Flash Mount
Found on the top of the camera over the viewfinder, this slotted head connects with the foot of the flash. Even new cameras which feature a built in flash have the capability to attach an external flash.
Tripod Mount
A threaded hole is usually inset in the bottom of the camera for attachment to the head of a tripod. There are two standard sized holes for the tripod mount. Check your manual to see which one you have so you can purchase a tripod head that will fit appropriately.

Inside the Camera Body

While computer technology has changed much about the inside of the camera body, the basic functions and parts are still basically the same as they have been, working in combination to control the amount of light that enters the camera and exposes the film.

Reflex Mirror
The mirror is the first thing you see when you remove the lens. The mirror reflects the image of an object or a scene onto a viewing screen so that focus, lighting, and composition may be evaluated. When the shutter release is pressed, the mirror moves up and out of the way to allow the exposure of the film. Afterwards, it automatically returns. If you listen closely, you can hear this motion. The impact of the mirror going up and coming down is called “mirror flap”.
expshutteropen.jpgOpening the back of the camera, you will find the shutter behind the reflex mirror and the lens. After the mirror lifts, the shutter slides away exposing the film. The shutter controls the amount of time the film is exposed. There are several types of shutters, leaf or focal plane, but they all do the same thing. When installing film in the camera, take care not to touch the shutter blades. They are easily damaged, and repair costs can be exorbitant.
Located in the top housing on the camera behind the viewfinder is a prism which directs the lens’s view from the mirror into the viewfinder. As the image passes through the lens, it is inverted. The prism restores the image to its normal appearance. Some top of the line cameras have a removable prism housing for interchangeable viewfinders.
Loading the Film
Most new cameras feature film drop-loading, where you put the film in your camera and close the door, and the camera loads the film automatically. In the older cameras, you have to thread the film onto the take-up spool manually. Many electronic cameras nowadays will not function unless a sensor is triggered which tells the camera that the film is loaded properly. Read your manual to find out how to load and unload film.
Film Pressure Plate
A smooth metal plate is located inside the back of your camera that presses against the film to hold it in place. It is supported away from the camera body with springs. Because the film slides across this plate, touching it or getting dirt on it is a no-no. Once in a while, gently blow it clean with a hurricane blower or the like. If this is damaged, you may notice scratches on your film, missed focus, or an unbalanced depth of field. Get it to the repair shop as soon as possible.
Focusing Screen
Every SLR camera has a focusing screen inside directly above the reflex mirror. Looking through the viewfinder, you will typically see something etched on the focusing screen. It may be a circle with two split halves, rectangular boxes, squares, or lines. Camera designers have created many aids that help you aim and focus the camera. In some newer cameras, the focusing aids are illuminated, and they can often be changed by the user. The change usually represents a change in the focusing ability, metering capabilities or view such as changing from standard to panoramic perspectives. Many cameras feature interchangeable focusing screens. These come in a variety of designs, but our favorite is an architectural grid with horizontal and vertical lines that helps with composition, specifically maintaining a level horizon. Be very careful not to scratch this screen when cleaning the camera.
Camera Meter
The meter is a tool inside the camera which assists the photographer in determining the proper exposure. There are three types of through-the-lens metering (TTL) found in cameras. All a meter can do is measure light entering the camera through the lens, and make a decision, and give you that recommendation. Center-weighted metering looks at the whole picture area but its decision is most affected by what is in the very center of the image. Spot metering determines the exposure by looking only at a very small part of the whole frame, usually marked by a circle or square on the focusing screen. Multi-pattern metering is one of the most sophisticated metering systems. It takes readings from different parts of the image and compares the results with information stored in the camera’s computer memory. It then figures out the highest probability of a particular kind of picture you have (backlit, evening light, sunset, etc) and reports back to the photographer the recommended exposure. Some cameras will give you all three choices and others will have only one. Check with your manual to determine what metering capabilities your camera offers.

The Manual

Time and time again we have mentioned consulting the manual for your camera. If there is one thing we never leave home without, it is our camera manual. Especially with the newfangled auto/computer everything cameras, it is a requirement. We are often out in the field with a new creative concept and can’t remember how to do it on the camera. Having the manual with you overcomes that hindrance. When you are sitting and waiting for a bus or airplane, or even for the moose to come strolling by, take it out and read it. You will learn all kinds of things you forgot you knew about your camera’s capabilities.


Take It Apart, Put It Together Again
In the chapter on Composition, we discussed understanding how your equipment works so that you will understand its strengths and weaknesses, allowing you to concentrate on the photography not the equipment. It is time to put that into action. Practice taking your camera apart and putting it back together. Take the lens on and off and change it with others, working towards being able to do it by touch and not looking at it. Do the same with the batteries. Take them out and put some in, then do it again and again. Do it so you aren’t paying attention, you are just doing it by habit.
What Do The Buttons Do?
Do you really know what all the buttons on your camera do? From the manual, make your own portable list of what the different buttons and custom functions on your camera do. Make it the size of a business card and laminate it. Put it in your camera bag so it is handy when you forget what something does.
Testing Buttons
Take a serious of photographs which test what the different functions and buttons on your camera can do. If you have controls for bracketing or multiple exposure, take some test shots to see what the results look like at the different settings. Does your camera have different timer functions? Test those to see how it feels when photographing at the different waiting times (like a 2-second delay or 15-second delay – what does that really feel like). Go through the manual and test drive your camera in the field with all of its different functions. Take notes in your manual because what it says and how you really understand it to work maybe two different things. Write it down in your own words.


  • Massey F. Jones
    Posted May 26, 2005 at 11:23 | Permalink

    Don’t change anything about your website. It’s lovely. I was a military (read professional) photographer for 30 years and understand all that is being presented. This is a website for the learned, not the dummies. Keep up the good work.

  • Posted May 26, 2005 at 15:34 | Permalink

    How kind. Thank you.

    We like to keep our site for the learned and the dummies who want to learn. We send the “willing to stay ignorant” elsewhere. :-)

    We’ve put a lot of work over the past 10 plus years on this site and it has been overalled quite dramatically over the years, too, as technology and styles change, but the content remains solid over time.

    Thanks a lot for the nice things you said. You’re someone who has truly “been there done that”, so it is much appreciated.

  • Kakai
    Posted January 26, 2008 at 22:48 | Permalink

    what is the function of a prism in a camera and the film speed scale?

  • Posted January 27, 2008 at 14:46 | Permalink

    The prism has nothing to do with the film speed. These are both explained in the article. The prism redirects the image to the eye through the viewfinder, flipping it over so you can see it “right side up” since it comes in actually upside down.

    The film speed scale tells you how fast the shutter speed is by the split second. 125 is 125th of a second. 500 is 1/500ths of a second.

Post a Comment

Your email is kept private. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.