Let’s Get Started Beginner’s Photography · 2011. 9. 11. · Shutter Speed Aperture Calculating correct exposure Diﬀ erences between shutter and aperture priority modes and

Lesson Two www.gulfphotoplus.com

All text and images copyright Robin Nichols and Gulf Photo Plus01

Content:

The Camera: Explore the functions of the program modes and understand how they relate the to creative and manual exposure control.

In detail this includes:

Depth of FieldIsolating a subject using a shallow depth of fi eld (i.e. small f-stop numbers)Average - shooting at the mid-ranges of the depth of fi eld (i.e. f8 – f11)Creating front-to-back sharpness (clarity) using large f-stop numbers ExposureShutter SpeedApertureCalculating correct exposure

Diff erences between shutter and aperture priority modes and related to real shooting situations.

CompositionPortrait vs. Landscape orientationCreating a ‘frame within a frame’

Welcome to Let’s Get Started: Beginner’s Digital Photography, a brand new, four-week course designed for all those starting in digital (and fi lm) photography, those that have been shooting for a while and needing a ‘refresher’ and anyone considering making the break from fi lm to digital.

While there are plenty of courses that off er a range of diff erent formats, this is the fi rst to incorporate the considerable benefi ts of face-to-face classroom tuition with the advantages of having Internet backup. This also works well for your assignments because you can complete them at any time within the confi nes of the course and simply upload when you have the time. No longer are students hampered by having to be physically present in class to complete the course (although of course there are also tangible benefi ts to being in the classroom) and if you get stuck or have a problem with one of the assignments, you can ask the experts any time throughout the course.

Let’s Get Started: Beginner’s Photography


All text and images copyright Robin Nichols and Gulf Photo Plus

Lesson Two: Let’s Get Technical

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Let’s Get Started: Beginner’s Photography

As a photographer you have tremendous control over your creative environment. You can use the two main exposure features, aperture and shutter speed, to make perfect exposures, or you can vary these settings subtly to create more clarity in the image or even to isolate the subject from the rest of the stuff in the scene. You can change the shutter speeds so that the subject is frozen in time, motionless, almost regardless of the speed at which it’s travelling. Or you can create really mystical eff ects with a tripod and an extended shut-ter time. Most of this is only possible with a camera that has a range of program exposure modes. Aperture, Shutter and Manual priority modes. In the shot below, I wanted everything to be as clear as possible so placed the camera on a tripod, set the aperture to the highest number (to give me a good depth of fi eld) and made the exposure. If I had simply pointed and shot, the camera would have produced an average result with camera shake (because of the long exposure and not tripod) and a poor depth of fi eld so not all the refl ection would have been clear (Canon EOS 400D, 1/4s @ f16, 800 ISDO).

Understanding Aperture

f16



Pointing and shootingWe have just seen how to create minimum and maximum depth of focus (also called depth of fi eld in our shot using specifi c aperture settings. If we simply point and shoot we can also get great results, albeit slightly unpredictable ones. In this example I didn’t think about the exposure, just put the camera into Program Auto mode pointed and this is what I got. A number of other factors aff ect how we get the results we get. The fi rst is the light. If it is bright, the camera can select a fast shutter speed and a high f-stop number, giving you crisp, clear looking shots but as soon as you walk into a dark place it begins to make decisions about shutter and aperture that you might not want. Program auto is a great place to start but be prepared to move into Aperture and Shutter Priority modes for the ultimate in exposure control. Another factor that has an infl uence over the result is the focal length of the lens. Wide and semi-wide angle lenses give a greater depth of fi eld than telephoto lenses. This landscape was shot using a 35mm semi-wide angle lens which explains why, at only f5.6, I still got most of the stuff in the frame sharp.

We have just seen how to create minimum and maximum depth of focus (also called depth of fi eld in our shot using specifi c aperture settings. If we

f5.6



Creating a shallow depth of focusTo create a minimum or shallow focus eff ect, we must be careful about precisely what we focus on. Using minimum apertures produces a shallow depth of fi eld, so if a mistake is made in the focusing, the eff ect is lost. Set the camera to shoot at the lowest aperture number, commonly about f2.8, and ensure that care is taken over focusing.

f2.8


All text and images copyright Robin Nichols and Gulf Photo PlusCreating a good depth of focusTo create an all-over, maximum sharpness in a picture, set the aperture to the biggest f-number that the lens can be set to. In a typical point-and-shoot camera this may only be f11. A D-SLR camera might go as high as f22 or f32,. Ensure that care is taken over focusing.

lens can be set to. In a typical point-and-shoot

f22



In many respects, the primary concern when learning to take pictures is to get the exposure right. We do this by combining our skills at seeing the selected scene in terms of grey tones, noting whether there are any specifi cally bright or dark areas within that selected scene, and then compensating for this using, typically the Exposure Compensation feature (more on this later).

In the fi rst lesson we briefl y mentioned that there are three fundamental features in a digital/fi lm camera that control exposure. These are shutter speed, aperture, and the ISO sensitivity. In this lesson we look at these three features in greater detail, how to control them and how changes in their characteristics aff ect how the picture looks.

For most beginners, understanding the relationship between aperture, shutter speed and ISO sensitivity is probably the hardest concept to grasp.

The aperture settings in your camera are similar to the iris in your eye. If the camera is functioning correctly in auto mode, the lens iris opens and closes, depending on whether the scene is dark or bright. This is the same for the iris in your eye, which

opens when the light level drops or closes when you walk out of a dark room into bright light.

Again, in the same way that our eye works, a digital sensor (the ‘CCD’ or ‘CMOS’ sensor) reacts to the amount of light received. Too much, and the picture is ruined because it’s too bright. Too little and the picture is ruined because there’s not enough light!

Unfortunately, because of cost and physical limitations, the lens aperture can only open and close within certain physical parameters, it has a ‘fi nite’ range of exposures (f-stops) that it’s capable of. For photographers needing to work in locations that have limited light, for example wedding photographers, you can buy lenses with very

Shutter Speed SuggestionsSports 1/50s +Formula 1 racing 1/2000s +Tennis players 1/2000sKids playing on the beach 1/250sYoung baby asleep 1/60 - 1/125sBoy on skateboard 1/125s – 1/500s

Fast Shutter Speeds1/4000s1/2000s1/1000s1/500sMedium shutter speeds1/250s1/125s1/60sSlow shutter speeds1/30s1/15s1/8¼s½sOne second, and slower…

Above and at Right: Shutter speed plays a huge part in getting your images sharp, or not. Shutter speeds of 1/60s and faster will ‘freeze’ a handheld shot while those slower than 1/60s require a very steady hand, or a tripod.

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Shutter speed & aperture control



specialised aperture setting ranges (for example, opening to maximum apertures of f1.2), but these come at a huge premium.

Another feature about lenses that is less understood is their ability to control how much detail is clearly produced in every shot. Typically we recognise the term ‘maximum focus’ in a landscape photo because everything from the pebbles in front of the tripod to the mountain range in the background come out pin sharp. This can be compared with the fashion portrait for example, shot using a ‘minimum focus’ technique so that the model’s face is relatively clear and sharp but the foreground and immediate background are completely out of focus (fuzzy). These eff ects are the result of manipulating a feature

called depth of fi eld. We don’t need to understand this concept to any great depth suffi ce to say we can create similar focus eff ects by changing the aperture (the ‘f-stop’), while being careful on precisely where (on the subject) the lens is focused.

To create an all-over maximum sharpness in a picture, we need to set the aperture to the highest f-number that the lens can be set to. In a typical point-and-shoot camera this may only be f11. A D-SLR camera might go as high as f22 or f32, depending on the model of lens used.

Going the other way, to create a minimum focus eff ect, we must be very careful about precisely what we focus on! Using minimum focus produces a

Locking the ExposureAbove left and right: Although all digital cameras come with increasingly sophisticated light meter technology, mistakes can still be made. This is why it’s vital to keep an eye on the LCD. Bright or dark subject matter is often at the heart of the problem. Point the camera in the ‘wrong’ place (top left, the dark door) and you get overexposure because the camera tries to brighten the scene. Move the camera a few inches (for example, over the white tile-work) and the results are diff erent. A fast way to solve an exposure hiccup is to half-press the shutter button and use the camera’s EV Lock feature (it’s like the focus lock). Half-pressing the shutter button takes a meter reading and focuses the lens at the same time. If you take a shot and it’s not perfect, reframe the image, and take another meter reading from a slightly diff erent part of the subject. Before pressing the shutter button to take the shot, re-frame the scene to where you originally wanted it. This is a technique called Focus and/or AE lock. Although designed for getting off -centre subjects pin-sharp, it also works with light meters on most cameras. If your doesn’t have this feature, check the manual. More than likely, it’ll be a separate button elsewhere on the camera.



shallow depth of fi eld, so if a mistake is made in the focusing, the eff ect is lost. Set the camera to shoot at the lowest aperture number, commonly about f2.8, and take care over the focusing.

Taken as an isolated eff ect, depth of fi eld gives the photographer immense power to isolate a subject from a background or to create a wide range of clear detail in something like a landscape panorama. However, as we’ve already learned, aperture is directly related to shutter speed. Think of this: if we are standing on the lip of the Grand Canyon and decide to get everything as sharp as possible using depth of fi eld, we’d set the camera to f22 or f32 if possible. This should be the ‘perfect setting’ to ensure that both sides of the canyon would be sharp and incredibly detailed. However, we also know that if we set the aperture to f32, it’s a very small hole in the lens so doesn’t let much light into the camera – so you get a very dark picture. How can this be fi xed?

The best way is to slow the shutter speed down so that, eff ectively, more light gets into the camera to compensate for the small amount of light allowed in by the tiny aperture. The danger here is that, if the shutter door is open too long, the subject will almost certainly be blurred. Obviously, in the example of a landscape photo, it almost doesn’t matter how long the shutter is open because the landscape isn’t moving, but you must use a tripod! For all other portraits and ‘live action’ photography we must make a mental note about the shutter speed so that we can get enough light to make the shot, but so that we end up with a blurred image.

While aperture controls the amount of ‘stuff ’ that’s in focus in the image, we can regard shutter speed as being able to ‘freeze’ movement. Typically, if we set the camera to Sport/Action mode, it locks the shutter off to a fast setting. In a point-and-shoot camera this might be 1/500s, but in a D-SLR camera, you can increase the shutter speed to 1/4000s, enough to freeze even the fastest-moving subject.

Above: Although digital and fi lm cameras are accurate, the auto meter can still be fooled if you choose a subject that’s predominantly white or black. In this case the meter over-reacts and produces a slightly grey (underexposed) result. Unless we check the LCD screen frequently and understand exactly how the image we see on the camera relates to the image on the computer, we can get a shock. How can we fi x this? If you know that you are shooting a predominantly white or dark subject, dial-in a plus (+) or a minus (-) amount in the camera’s exposure compensation feature (at lower left).

If your camera does not have the EV or Exposure Compen-sation feature, try using the Beach and Snow mode.

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Aperture speakA fast lens is one that has a lower or wider maximum aperture than the standard lens aperture. Fast lenses are often very expensive and have maximum apertures of f2.8, f1.4 or even f1.Wide open refers to a lens that has been set to its smallest f-number to enable the maximum amount of light to pass into the cameraStopped down refers to the aperture when it’s set to the maximum number, typically f11 on a point-and-shoot camera, and f22 on a D-SLR camera.Stopping down implies that you get a great depth of fi eld or maximum scene clarity by setting the aperture to f22.


All text and images copyright Robin Nichols and Gulf Photo Plus06

Relationship between Aperture & Shutter speed Let’s say that the exposure, calculated by the camera in the top frame is good. The photo looks bright and clear. If the aperture (iris) is then changed to a higher number (ie from f2.8 to f4) less light gets into the camera to make the picture. So, if the other part of the ex-posure formula, the shutter speed, is left untouched, the result will be an increasingly dark image. But, if the shutter speed is changed to compensate for this image darkening by slowing its speed down (effectively letting more light into the camera) the result is a perfect exposure, albeit one with slightly different clarity (because the aperture, remember, controls depth of field or ‘how much stuff’ we get sharp in the picture). Although this sounds like a perfect solution, bear in mind that if we drop the shutter speed below about 1/60s, we are quite likely to blur the resulting image, unless a tripod is used.

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Deliberate Movement Effects Sometimes it’s fun to deliberately blur part of the shot to add a sense of activity, ‘purpose’ and movement. In this example I set the camera to a shutter speed of 1/25s which, in Shutter Priority Mode, gave me a corresponding aperture of f2.8, the widest aperture the lens has. To make sure that I got a blurred result, the camera was set to the lowest ISO rating (in this case, 80). If I wanted to freeze the bicycle passing the camera, I’d have to shoot at ISO 400 or, better still, ISO 800, giving me a shutter speed of around 1/250s...



Exposure Pointers As with all things to do with photography, there’s always a chance to make mistakes. Here are some of my own examples of successes and failures. Top left: Shooting indoors with little light. I sued a Night Portrait mode to get this part sharp/part blur effect. The camera flashes but exposes for longer capturing some of the ambient light and the movement. Top right: Great food deserves to be photographed. There was not much light in this restaurant so I had to use a fast ISO setting and an aperture that was wide open (at f2.8) to get this result. Left: You really don’t have to think too hard to get this type of shot because it is bright and the camera makes all the right decisions because there is a lot of light. Lower right: Here’s a typical mistake we all make - shooting in a place with poor light with no flash. To fix this I should use flash or raise the ISO to its maximum (i.e. to ISO 800)

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Composition: Shooting Vertical or Horizontal

One of the most important things to practice is picture alignment. Most people take a snap in the landscape format, that is, horizontally, even if the subjects are predominantly vertical.

It makes sense to check the subject and then frame accordingly. After all. If you shoot a vertical build-ing horizontally, you include a load of additional stuff either side of the subject that’s irrelevant to the shot so why bother? As a rule of thumb, I always try to shoot a frame vertically and then do the same subject horizontally. It’s digital, it’s not costing anything to snap multiple frames and you might like the result. The Hong Kong ferries work well in both alignments but the ones on the following pages are specifi c to one alignment only...

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Vertical framing No prizes for getting this scene in the right alignment. Because I used a 400mm zoom lens to bring the buildings closer to me, it appears really magni-fied while the perspective is compressed. Although this would look OK in horizontal format as well, I think the vertical shape of the skyscrapers relate well to the frame alignment.





Like many of the strict photographic ‘rules’ most can also be broken, or at least ‘bent’, to assist in fitting what you want to shoot into how the rules dictate they should be shot. One of the best photo composition techniques is to use a window to frame a shot. By this I mean, shoot through a window, arch, doorway to add a frame around the subject, whether that’s a portrait or a landscape.

There are several reasons for doing this: you can use the framing device to exclude stuff that gets in the way of the ‘real’ subject, you can use it to disguise a location and even to remove or hide a lack lustre sky or distant hillside. The example at right, shot in the old granaries in Meknes, Morrocco, beats everything I have done so far with a total of 11 ‘frames’ in the same shot! Overkill maybe, but it gives a really good impression of the place. Small wonder that it’s such a popular choice for so many foreign filmmakers to use as a location. Below are a couple more examples of filling the frame while shooting through an arch for effect...

Composition: Framing the shot

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Very often you can use the viewfi nder extract or isolate elements in a scene so that the viewer’s eye is concentrated on repetitive lines within the frame. The fabric hung out to dry formed a perfect arrangement against the blue sky. I moved in as close as possible using the tele zoom lens to exclude the roofl ines and other distracting elements. (Program Auto mode, 1/400s @ f7.1)

When I saw the light poking through the bamboo roofi ng in Marrakesh’s old souk I deliberately underexposed the shot (using the Exposure Compensation feature set to minus two f-stops) to emphasise those amazing fi ngers of light probing the alleyway’s darkness like a laser beam.(Program Auto Mode, 1/50s @ f4)

Using Lines

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Lesson Two: Assignment Take a photo that’s best suited to the Landscape and Portrait orientation.Take these photos using diff erent depth of fi elds (i.e. f2.8 and f22 if possible)

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Let’s Get Started Beginner’s Photography · 2011. 9. 11. · Shutter Speed Aperture Calculating correct exposure Diﬀ erences between shutter and aperture priority modes and