Equipment Share your camera knowledge!

As requested in this thread, here's what I've got so far. A lot of it's really basic, but I'm not sure what level it's supposed to be written at so meh. If I've missed anything out please do contribute, or if I've got stuff wrong let me know. The section on aperture probably needs to be rewritten - I had no idea how to word it. In the ISO section it might be handy to get some feedback from people who own different cameras on how they perform at high ISO etc.


Basic Terms

ISO
In film terms, this is the sensitivity of the film to light. However, in digital terms this is the sensitivity of (or amplification of the signal produced on) the sensor. Therefore, to get a well-exposed photo, less light is needed (the shutter needs to remain open for a shorter length of time) when using a higher ISO. There is one disadvantage to using a high ISO (800, 1600 or 3200 for example) though; noise levels increase leading to a horrible mess of oddly-coloured pixels if the camera performs particularly badly at high ISO.

Digital SLRs tend to perform better at high ISO, with Canon leading the pack as regards noise levels, however many compacts which perform well above ISO 200 have been released.

<examples needed>

Shutter Speed
This is essentially the length of time for which the sensor is exposed to light. A general rule is that to counteract the effects of hands shaking the camera, a shutter speed of 1/focal length should be used. For example, when using a 200mm lens, a shutter speed of 1/200s would be an acceptable minimum. This rule is not always applicable however, and depending on how steady your hands are, you can get away with much slower shutter speeds quite often.

Aperture/f-stop
The aperture of a lens is essentially how wide it opens to let light in. The actual amount of light being let through the lens is defined as focal length/f-stop. Therefore with an aperture of f/1.8, this value would be 1/1.8th (around a fifth) of the focal length. Aperture and shutter speed work in tandem to control the exposure of an image. A larger aperture (smaller f-number) will brighten the image, as will a longer shutter speed. The advantage to using a larger aperture (if you hadn't guessed already) is that you can use a faster shutter speed to freeze motion much more effectively. See the "How do I get this effect" section for more notes.

More to come soon...

 

How do I get this effect?

Shallow Depth of field
This is incredibly popular in portraits since it helps isolate the subject from the background. All you need to do is use a wide aperture (low f-number) and the depth of the image in focus will decrease. Likewise, if you want to get everything in focus, use a high f-number such as f16 or f22.

Set camera to Aperture priority ("Av" or just "A" on the dial) so that it automatically calculates shutter speed to compensate for the wide aperture and prevents overexposure of the image. A low ISO rating may help.

Funky blurred water
To blur running water, a long shutter speed should be used. Depending on the speed at which the water is flowing, a good blur can be achieved with an exposure of 2-3 seconds, however a smoother effect might require an exposure of 20 seconds or so.

Set camera to Shutter priority ("Tv" or "S" on the dial) so that it automatically calculates the correct aperture setting to compensate for the long shutter exposure. A low ISO rating again may help. If the image is still overexposed, use a neutral density filter, basically sunglasss for the camera. A rating of 0.6 should generally be sufficient.

(Sorry to interrupt. --Nexxo)

 

A lot of my friends were asking to explain such things so I had a little written for them explaining ISO and etc. link

[if the link is not appropriate here tell me I'll remove it]

 

Hey Nath...I really don't want to steal your thread and I think it's a great idea about sharing ideas and such and my intentions are completly good and honest and not mean in any way and bla bla bla...

But there is an excellent book that covers everything about photography...and its pre-digital too. Why do I say pre-digital? because everything explained in the book teaches the skill of photography. And with a ton of practice you can pick up any camera, digital or film, and be able to use it to your max ability.

Here's the title: The Photographer's handbook by John Hedgecoe, 3rd edition.

 

There is actually more then one, closer to say....200 good books that cover the basics of photography. It is a subject that is heavily written about.

 

It's no problem at all - the intention was to have anyone who is able to contributing.

 

Wrote by me for a local Car Forum, but every bit as useful here.

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I think it's a good idea if I start typing up some tutorials that cover the basics in Photo theory on here, as once you understand these, it all becomes SO much clearer, and you'll no longer be scared of that manual setting

There's no way to avoid some of the more technical issues, because they're the foundations of photographic theory, but I'll try to keep the maths and stuff a bare minimum.

The following rule however, is the cornerstone of exposure theory, and should be learned. I've used some analogies that make it easier to understand, so hopefully even those new to the hobby can get to grips with using a camera manually.

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Reciprocity Law



The trick to exposure, is understanding something called reciprocity law. Basically, you can't just use any shutter speed you want, because the relationship between shutter and aperture are linked... it's reciprocal.. hence the name. Basically, think of a lens as a tap, but instead of letting water in, it lets light in. There are two ways you can control the amount of water (light) that flows through your lens (tap).

Aperture (the amount you open the tap). Basically, this is the size of the hole that lets the light in. The bigger the hole, the more light flows through.

Shutter (the amount of time you open the tap for). The more time the shutter is open for the more light flows through.


So thinking of a tap: If tap A is open halfway for 1 second it will flow X amount of water. Tap B however, is open all the way for 1/2 second.... that also flows X amount of water. The result is that the bucket (your film or chip) contains the same amount of water (light).

Start thinking about it as the water analogy until you get your head around it.

The amount of light received by the film is referred to in "stops". The name comes from the "stops" on the lens aperture ring (most modern cameras no longer have this), but the same name applies to shutter speed as well because they both control the same thing: The flow or amount of light (water). Get it?

Aperture stops:

F1
F1.4
F2
F2.8
F4
F5.6
F8
F11
F16
F22
F32

As a diagram, it would look like this



Here are some images of a real camera lens showing the aperture blades in action at various settings.



Shutter speed stops.

These are just fractional numbers denoting time.

1 second
½ a second
¼ second
1/8
1/15
1/30
1/60
1/125
1/250
1/500
1/1000
1/2000
Etc

Your camera may not have all the same f numbers or shutter speeds, but don’t worry about that.

Modern cameras are also capable of using values in-between stop as well, such as f13.6 or 1/235th sec. Don’t worry about this for now either.

Any given amount of light is called a “Exposure Value”, or EV. Because the reciprocal nature of aperture and shutter speed, an EV can be made up in many different Combinations of shutter speed and aperture. This is the main concept behind Reciprocity Law.

For example:

EV0 = a shutter speed of 1 second @ f1. So thinking back to the tap analogy, can you guess another way to get EV0?

If it’s 1 second at f1, then 2 seconds at f1.4 will give the same amount of light, and therefore the same exposure.

If you make the aperture smaller (larger f number), you use a longer shutter speed (bigger number), and vice versa. Just like the tap. If you want to fill the bucket (expose the film) in half the time (twice the shutter speed), you need to open the tap more (use a wider aperture – smaller f number).

Just remember, that with aperture, the higher numbers mean less light (smaller hole), and shutter speeds with larger numbers are shorter because they’re fractions…. 1/30th second is longer than 1/60th for example.

The only thing to remember, is if you go longer than 1 second… then the numbers will start going up again the other way… 1 sec, 2 seconds, 4 seconds etc… For now though, until you get your head around it, just assume that 1 second is the longest you’ll ever use, and 1/2000th of a second the shortest.

So if a light reading is saying we need 1/125th @ f8 reciprocity states that we can also use the following

1/2000th @ f2
1/1000th @ f2.8
1/500th @ f4
1/250th @ f5.6
1/125th @ f8
1/60th @ f11
1/30th @ f16
1/15th @ f22
1/8th @ f32

Look at the relationship between those numbers!

As shutter speed increases (higher number), we have to stop down (open up the lens – smaller number) by a corresponding stop.

All those combinations will result in EXACTLY the same exposure.

That’s Reciprocity Law.

Practice this, until someone can say to you “Sixtieth at F8” and you can then recite all other combos that give the same EV. When you can, then you’ve cracked it, and we’ll move on to WHY there are so many settings that give the same EV and WHAT the effects of each are. While they give the same exposure, they do however, give lots of different effects.



Just remember the relationship.

Exercise….

Your meter suggests 500th sec @ f4

What aperture do you need for 1/60th of a second.

NB. Your camera may not display as a fractional number… it may say “500” instead of 1/500th.


Next up…. Light Meters: Why they're god damn bare faced liars!

 

Light Meters: Why They Are Bare Faced Liars


So we now know understand what these numbers mean, but how do we know what numbers to use in the first place?

If you read and understood the last part, you’ll know that a “EV” can be made up of a range of shutter speeds and apertures that give the same value. That’s great, but we need to know what the correct EV is for a scene, or understanding the numbers won’t help you get a correct exposure.

To do this we use a light meter. If you have a camera, you also possess a light meter, as most modern cameras have one built in. Some professional cameras don’t have any light meter at all, but most these days do. Do not however, assume that what it’s telling you is always correct, because 5 times out of 10, it won’t give you the best exposure. So why bother? Because it’s only doing it’s job, and like most tools, it requires skill to wield it correctly: Having a full Snap On toolkit doesn’t make you Adrian Newey, and likewise, owning a Nikon D3 doesn’t make you Nick Knight either.

18%

All in-built light meters measure the same thing: Reflected Light! That’s important to remember. They measure the light bouncing OFF a subject and heading back to the camera. Because most scenes are made up of a massive range of colours, tones, levels of brightness etc (just look out of your window now… count the colours, look at the difference between the lightest and darkest bits), the meter has to average these out. I won’t go into theory too deeply here, as it’s beyond the scope of this post, but suffice to say that it’s been determined that the average scene can be represented by a surface that reflects 18% of the light falling upon it. Also, as scenes are made of many colours, we’ll average that to grey as well. So a light meter will suggest a setting that will correctly expose a 18% grey card as 18% grey. (more on grey cards later).

That’s great if you’re photographing a grey card that fills the entire frame, but you’ve got to be a special kind of person to do that

As some scenes contain massive differences between light and dark, the averaging type of meter often gets things wrong. We need to know how to interpret the readings it gives us.

To better understand what a light meter does, here’s an example.


Here's a shot of a battery sitting on a piece of white paper.



I've reduced the image to greyscale so you can more easily see what's going on here.

As you can see, it's a mid tone battery on a white piece of paper as it should be. Want to see what a camera's auto exposure did to it?

Set to auto exposure the camera produced this.




Why? Because your camera's meter takes an average reading of the whole frame and determines an exposure value that will render it a mid tone.. usually 18% grey. It does this because most outdoor scenes with a range of tones from light to dark can be well exposed by doing this. However, when teh background forms the majority of the frame, as you can see, it fails.

To further illustrate my point, i placed the battery on a black piece of paper, and this is what the camera did.




You'll notice that the paper has been rendered exactly the same shade of grey as the previous pic, yet in reality, one was white, and the other black. Because of this, it's the battery that's been wrongly exposed, not the paper. (none of these images have been corrected in photoshop etc)

To transfer this example to real life… you’re probably more familiar to a scene like this.




I held my hand up against the window, and photographed it.

As you can see the one on the right is what resulted. The meter was fooled into thinking it was the background I wanted correctly exposing, because that was the largest area of the image, and being the brightest forced the camera to expose for that. The result is a dark hand. WHy? Because the background was so much lighter than my hand. It's tried to average out everything to 18% grey.



On the left is a correct exposure for the hand.. on the right is how most auto exposure modes will render the scene if left on Auto.


Basically, the camera had no idea it was the BATTERY (or hand) I wanted to photograph, NOT the piece of paper (window) it was sat upon (in front of).

That’s the problem with meters: They’re accurate, but stupid.

Grey Cards

So… how do we tell the camera it’s the battery we want? By understanding what it’s trying to do. It’s measuring the amount of light that’s bouncing back off the subject regardless of colour, contrast etc, and giving a reading that will correctly render an 18% grey card as 18% grey.

So if we actually measure the light from a grey card, then in theory, it will give us a nicely exposed scene regardless of what’s in it.

The first piece of advice I can give you, is go buy a grey card. Jessops sell them. Don’t think you can use a piece of paper scribbled in with a HB pencil… you can’t. A proper grey card is a finely calibrated tool… it’s exactly grey, and it reflects exactly 18% of white light falling upon it. They cost a few quid, but if you want to get correct exposures, every time without forking out for a hand held meter, get one!

To use a grey card point your camera at the scene as you normally would (if it’s on a tripod this is way easier) then before you take a light reading, hold up the card in front of the camera so it’s filling most of the frame (preferably all of it) with the card perpendicular (square on) to the lens, and then take a reading… then set the camera to what it suggests in manual mode*. Remove the card… take the photo. Its as easy as that. Make sure however, that you, or your camera does not cast a shadow upon the card or it will give a false reading (particularly important if the sun is behind you). Basically, in most outdoor situations it will work so long as the same light that’s lighting the scene is also falling upon your grey card.

By doing this we’re ignoring the scene, and just measuring the amount of light falling upon it instead. This method will give more reliable results, more of the time (if done correctly will be almost 100% of the time).

Of course, if your camera does not have a manual mode, you may have to hold the card in front, and then use AE lock by pressing the shutter halfway… the problem with that, is that will also lock FOCUS on the card as well.

In short… to really get creative with photography, you need a camera that gives manual control, or at least allows you to lock exposure separately from focus. A fully auto only camera will always lead you around by the nose and give you little control.

One way around this, is Exposure Compensation. Not all cameras have this, but if you have a fully auto camera that does, then it’s your “get out jail free” card, and you can get away with it. It’s not as exact as using full manual, but will get you out of trouble. Referring to the hand images above, you can set + exposure compensation to force the camera to let more light in when your subject is in front of a bright background, or less light when in front of a very dark background.

Hand Held Meters

Another way of metering is by using a hand held, or “incident” meter. These measure the light falling ON the subject rather than reflecting OFF it. They give the same results as a grey card… without having to use a grey card. There are loads of different types, some costing thousands, but to this day, I use a Sekonic L308. It’s small, light and easy to use.

With a hand held meter, you stand AT the subject, and point it back to the camera so you are measuring the light that’s falling upon the subject. For instance: If you’re taking a portrait… walk over to the sitter, place the meter directly in front of his/her face, and point it back towards the camera, then take a reading.

Out of the above methods, an incident reading is the most accurate, and the one most professionals will use. The grey card will give equally as good results if used correctly, but is more of a pain in the ass. Using the camera’s meter alone is the least reliable.

Having said that, some cameras use matrix, or evaluative metering. Basically, they will split the viewfinder up unto sections, take separate readings for each section, and then average them out. Modern cameras such as the Canon EOS400D or Nikon D300 etc will use this method, and will be fairly accurate most of the time, and not be as bad as older, or basic cameras, but they still get it wrong.

Grey card or incident metering is the only way to get it right, all the time.

At this point though, it's worth noting that most cameras and films can only record a certain level of contrast, usually a total of around 4 to 5 stops maximum, so about 2.5 stops each side of the mid range tones. If the scene has more contrast than that, then something will be too light, or too dark. So no matter how accurately you meter, make sure there's not too much contrast. For example.. if you're photographing someone sitting in deep shadow from a wall, but the rest of the scene is in brilliant sunlight, you can usually only expose for one or the other - not both. In this situation, move the subject into the light. No matter how accurately you meter the scene, you won't get everything if the contrast is outside the range of the chip (or film).





*most cameras have a command wheel that allows you to manually set aperture and shutter speed, and you vary one, or both of these until the moving needle, or LCD diplay registers as “o”. See your camera’s manual for exact instructions once you read and understand this article, and also part 1 of this thread.


Next up…. ISO… What the hell is it, and what does it do.

 

Your Camera's ISO Setting


ISO (ISO (International Organization for Standardization)

This is a method of determining a film’s (chip’s) sensitivity to light. Like all photographic measurements, it’s calibrated in stops, i.e.,

ISO 100
ISO 200
ISO 400
ISO 800
Etc

The higher the number, the more sensitive the film or chip, and thus needs less light. The lower the number, the less sensitive it is, and needs more light to give the same exposure.

For example:
Using what we’ve learned already, if a ISO100 film needs 1/60th of a second shutter speed at f8 (1/60th @ f8) then a ISO200 film is one staop faster… or needs one stop less light.
1/60th @ f8 for ISO100
1/125th @ f8 for ISO 200
1/250th @ f8 for ISO400

Etc

You can also alter the aperture instead of shutter speed, e.g
1/60th @ f8 for ISO 100
1/60th @ f16 for ISO200
1/60th @ f22 for ISO400

The good thing is, you rarely have to change the ISO, and you can just concentrate on shuuter and aperture. ISO is less important now than it used to be, as fewer and fewer of us are using film. Digital cameras still have a ISO setting though. Why is this?

Imagine you leave your camera on it’s default ISO setting (usually 100) and you’re trying to take a photograph of a fast moving object. This as you will imagine needs a fast shutter speed to freeze the movement (more on this next tutorial). So you set it to 1/1000th of a second, as that will pretty much freeze most things. Remembering reciprocity, we now know we need a larger aperture (smaller f number). So we open up our lens as wide as it can go… and the camera (or light meter) is still saying it will be underexposed. What can we do then? The lens won’t go any wider, and we can’t lengthen the shutter speed because we need to freeze the action. Well… start thinking in stops. If the meter is saying we’re still 2 stops under exposed with our lens on it’s smallest f number, we can still get another 2 stops by increasing our ISO setting (or loading a film 2stops faster).
So why set it to 100 in the first place?
Like all things… there’s no free lunch. There’s a pay off. With film, the faster it gets, the more grain you get, and the image is less sharp. With a digital camera, there’s more noise if you set it higher. Try it yourself: Take some shots with your camera set to ISO100 and then at ISO1600 or as high as it will go. You’ll notice far more noise on the higher settings.

In short, if you can get away with leaving it on ISO100.. do so. If you need more light but need a fast shutter speed and your lens is already wide open, you can increase the ISO setting.

The alternative is also true. If you need a long shutter speed on a bright day, and your lens is already at it’s smallest aperture (biggest f number), you can reduce the ISO to 50 or whatever the lowest is on your camera.
Use this as a last resort though, and is only really useful when you need to use faster speeds in low light.

Next up: Shutter speeds and Depth of Field – The differences between EVs.

 

Ok... the Juicy Stuff.

So.. armed with the above theory, what can we do with it?

Well.. loads. Some, or all of which you will probably have stumbled across accidentally. Lets put it all together so there are no more accidents

Depth of Field

Earlier, we learned about the reciprocal relationship between aperture and shutter speed, and that there are more than one combinations of these that result in exactly the same exposure. So why do we need to know how to use them all? Simply put, aperture and shutter speed each change certain characteristics of an image other than the exposure (amount of light).

Aperture.

The most noticeable effect of this is depth of field. The correct definition of Depth of field is "the extent of acceptably sharp focus in front, and behind the point of focus". So if I focus on something 5ft away, the depth of field is how far I can move that something forward and back before I have to re-focus the lens.

Here's an example.

In the first shot, the shutter speed was 1/4 sec with an aperture of f4, and it gives this result.




Here's the second shot. As we learned earlier, using reciprocity, we can also use 4 seconds at f22 (remember you can go past 1 second as well, and then it becomes 2 secs, 4 secs, 8 secs and so on)... so that's what I used: 4 seconds @ f22



As you can see, the exposure is pretty much teh same.. it's no lighter, or darker. However, look closely.. you'll see some rather striking differences.

In the first shot, the only thing in focus is the pair of headphones, because that's what I focused on. The speaker behind, and the mouse in front, are soft and out of focus.

Now look at shot 2. While still not in razor sharp focus, you can see that the whole shot, from front to back is almost completely sharp.

This is depth of field in action, and it's a direct result of aperture.

Here's a diagram to illustrate.



As you can see, as we stop the lens down to a smaller aperture (bigger number) the area behind and in front of the object we focused on also starts to come into focus. In reality, only the actual point we focus on is ever in sharp focus, but the area of acceptably sharp focus is greatly increased.

You'll also notice that the area of sharpness behind teh object in focus is always greater than that in front. This stands true for all lenses and apertures: There's always more depth of field behind teh object than in front.

The focal length of the lens itself plays a big part too. Wider lenses (shorter focal length) lenses display more depth of field than longer ones. In reality, they don't, but due to magnification, the visible results give the impression of more depth of field, and that's all we're bothered about in this article. For example, the diagram above is for a 18mm lens. If we were to use a 200mm lens for the same aperture, the diagram would look more like this.



Obviously the objects concerned will be further away, as that's when we generally need to use a longer lens, but relatively, the depth of field is compressed, and not as deep with a longer lens.

To sum up.

SMall apertures (higher f numbers) give more depth of field, and wider apertures (smaller f numbers) give a more shallow depth of field.

So by using reciprocity law, we can determine the best aperture/shutter soeed for any given exposure depending on what effect we want.

If you want a blurred, soft backdrop to highlight your subject, and your meter suggests f11 @ 250th, you know that you can open up your lens to f4 and speed up the shutter to 1/2000th and the exposure will be identical.. only the DOF will have changed. A faster shutter speed will freeze movement more, but as in this case it was fairly fast to start with, only the DOF will have changed.

So by understanding Reciprocity, we can choose a shutter/aperture combination that suits our needs.


So.. that’s aperture, and we now know what effect it as on the image, and how we can choose the best aperture for what we need: Landscape for instance, will probably benefit from a small aperture (large number) so you have great depth of field from front to back, where as a portrait may well benefit from a large aperture (small number) to blur a distracting background. Brilliant… but as we know, adjust the aperture, and we also have to adjust the shutter speed to maintain the same EV (reciprocity law). So what effect does shutter speed have?

Shutter Speed

Well, this is probably the easiest to understand, and probably the most obvious. Long shutter speeds will not freeze action, whereas short ones will. Sounds pretty obvious I know, but there are a few things you need to be aware of. Also, there are some creative uses for a shutter speeds that mean you sometimes need to do the opposite of what you think you should.

Let’s start with the basics: Shutter speed is simply the amount of time the shutter is open for, and is measured in fractions of a second or even whole seconds if the light is low. SO if we want to freeze action, we use a very short shutter speed such as 1/1000th of a second. If we want to photograph a city nightscape, we put the camera on a tripod and leave the shutter open for many seconds to allow the much smaller amount of light to “build up” on the film, or chip. This leads to one thing you need to consider: Camera shake.

Curing the Shakes

As a general rule, shutter speeds of 1/30th of a second, or lower are usually too long for hand held use (but this figure will rise if you use a longer lens.. for e.g, a 300mm lens will be hard to hand hold at less than 1/300th sec). You’ve probably noticed this yourself in low light with no flash.. the image is blurry. You know it was in focus at the time you took it, yet it’s still blurry. This is because your auto exposure picked a low shutter speed because it was dark. Most fully automatic cameras will pop up the flash at this point to allow more light, but to be honest, unless you’re photographic anything that’s moving, you’re better off using a tripod and switching your flash off. (More on this subject later). We simply can not hold a camera still enough for 1/30th of a second or longer. Because the camera is basically moving, despite how still we think we’re holding it, the shutter speed is now long enough to record this movement.

You also need to consider the relationship between aperture and shutter once more: If we select a fast shutter speed to freeze action, then because of reciprocity again, we also need a wider aperture to let more light in. Most fast action shots will therefore by default have a quite shallow depth of field. The only way around this is if the light is exceptionally bright, or you’re using a very wide lens (refer to the depth of field section and diagrams). You can also set your ISO setting to a much higher speed, and this can often allow you to decrease the aperture size by a few stops. Generally though… a fast shutter means a wide aperture, and unless it’s very dark, a slow shutter means a small aperture.

Freezing Action

The effects of shutter speed are pretty self explanatory really.

Again, I’ll use reciprocity to illustrate:

Shot 1: 1/500th @ f5.6




The silver car driving past at around 30mph has been frozen completely because in the 1/500th of a second the shutter was open, it hadn’t moved enough to register any movement on the film.

Shot 2: 1/15th @ f32



Because of reciprocity the exposure is the same... e.g.

Shot 1 was 1/500th @ f5.6 and shot 2 is 1/15th @ f32

Remember, as we increase aperture, we have to decrease shutter speed… so

1/500th @ f5.6
1/250th @ f8
1/125th @ f11
1/60th @ f16
1/30th @ f22
1/15th @ f32

The exposure value is identical in both shots as you can see, but the difference the shutter speed has made is obvious. The car is now very blurred, because it travelled further over 1/15th of a second than it did over 1/500th of a second… because.. well.. it’s a longer period of time

Because all of the objects were fairly far away, depth of field was not an issue, but were there any objects close to the camera, they would have been out of focus in shot1 but much sharper in shot 2. Why is this? Because shot 1’s shorter shutter speed required a wider aperture, and wider apertures give a shallower depth of field. In fact, in shot 2, you can start to see the rain on my window as the depth of field is now so much deeper. In shot one, the fast shutter speed required a much wider aperture, and the shallow depth of field blurred out the rain on the window entirely. Shot 2 uses a smaller aperture, and the greater depth of field is now starting to render the rain sharp enough to see.


So.. armed with this info, we can now work what shutter speed we need for any given situation. Cars need fast shutter speeds if they’re moving, right? Well… yes, but only if you WANT them to be frozen. With a moving car, it is often desirable to convey movement, and freezing it entirely just makes it look static. For all you know I could have lied and the car in shot 1 wasn’t moving. It was of course, but you can’t really tell.

So how do we convey movement? The best way is a slow shutter speed “Hang on a minute”, I hear you say… “ You just said you need a fast speed for a moving car”. Yes.. you do. If you want to freeze it, but a slow shutter speed will convey motion. As you can see though, it also blurs the car beyond recognition. So how do we convey motion, yet keep the car sharp?

Panning.

No.. not panning for gold.. Panning is a term that means tracking, or following a moving object with the camera.

Look at the photo below.



It was taken with a shutter speed of 1/60th of a second. Not very fast.. in fact, just one stop above the limit for hand holding. Yet the car is sharp. This is because I tracked the object as it sped past, keeping it in the same place within the viewfinder. As a result, the car’s speed relative to the camera was very small. Instead it’s the background that’s blurred, which has three benefits:

1. It isolates the car from an otherwise messy background
2. The blurred background denotes speed more than if the entire shot was sharp by using a much higher speed.
3. And blurring the background cancels out the very deep depth of field the smaller aperture would have given us (slow speed- small aperture… fast speed – large aperture).

It also means the wheels are blurred to help denote speed further. This is because the wheels are rotating, and not merely moving in one direction.

Panning is difficult. It will take practice, and your first attempts will be terrible, but stick with it, as it doesn’t take long to master. Hold your camera firmly in both hands, tuck your elbows into your chest so your upper body are rigid, and pivot your entire body from the waist, with your feet firmly planted wide apart. You look like a tool, but it works. Practice doing this first by just keeping the car in one place within the viewfinder as it drives past. Panning does require a slowish speed to work though… 1/30th, 1/60th… nothing higher than that. Once past 125th you’ll start to freeze the car again like in my shot 1 above, and this cancels out the whole object of panning.


How fast do I Need to Freeze Action?.

Good question. It depends on what you’re photographing? Most cameras these days go up to 1/2000th of a second, and that can stop almost anything. Fast cars, athletes, football action... most every day things. Getting a day bright enough to let you use it is the hard part! Increasing the ISO setting will allow faster speeds on a dull day, but remember the pay off: More noise or grain.

Some cameras go up to 1/8000th, and this, to be honest, is over kill. This can stop a bullet. It won’t be dead sharp.. you need strobe equipment for that, but it will stop a bullet to the point where you can clearly see it’s a bullet.

Basically, most decent cameras have a range of shutter speeds that can cope with most things you’re likely to come across.

Night Photography and Shutter Speeds

What about slow speeds? How do you meter for those? Fortunately, most light meters do go down to shutter speeds that amount to many seconds, and usually, that’s enough for most night shots in brightly lit areas, but sometimes, if you need a deep depth of field (hence you need a small aperture) you’re going to need a very long speed. SO long in fact, that it may go off the end of the camera’s shutter speed range, as some cameras have a longest speed of 30 seconds. Well.. Reciprocity Law to the rescue again. If you find you don’t have a shutter speed long enough for your given aperture, you can meter with the lens wide open. Let me give you an example:

You want to shoot a car in a city street at night. There’s lots of detail in the scene behind that you want sharp, but you also want the car sharp from front to back. This is going to need a small aperture.. let’s say for argument’s sake, f22 (refer to the depth of field section). Yet your camera is saying even at 30 seconds, it’s under exposed. Well, although you need f22 for the shot, you don’t have to meter at f22. This is why it’s good to be able to work out reciprocal EV settings in your head, because if you open up the lens to it’s widest… again for argument’s sake f2.8 and you now have a correct shutter speed of 8 seconds, you can work backwards:

8 sec @ 2.8
16 sec @ 4
32 sec @ 5.6
64 sec @ 8
128 sec @ 11
256 sec @ 16
512 sec @ 22

So there you go.. 512 seconds.

Wow.. but my camera doesn’t have such a long exposure time! Well. If that’s the case, you may now be exploring the limits of a consumer grade camera, as some will not allow what is called a “bulb” setting. The name, comes from times past when you could remotely release a shutter using a pneumatic cable and a rubber bulb you squeezed… the name has stuck, and now a “B” setting means that the shutter stays open for as long as you press the shutter.

The shot below is a great example.



This shot is a digital montage of many shots.. most of which are studio shots, but the sky is genuine. I had to use a 40 minute exposure to get eth stars to form trails on the film… and yes it was film, as even though my digital cameras have a “B” setting, the batteries would have been flat after 40 minutes with the shutter pressed! I used a Nikon FM2… completely mechanical and needs no batteries… so obviously it’s a film camera

If your camera doesn’t have a B setting, then you may be forced to shoot at the widest apertures you have at night, and this can cause you depth of field problems.

Another reason to get used to all this course, and using manual exposure, is because at night, your camera WILL choose a wide aperture for you no matter what you want. Using the scary “M” mode will allow you to over-ride this and use whatever aperture you need, even if your meter can’t register shutter speeds long enough.

Another problem with night shots, or ant time exposure is camera shake. Now, if the longest speed you can hand hold is around 1/30th, then you’ve no chance at 30 seconds! It’s time to buy a tripod.

Even then, your very act of pressing the shutter can introduce camera shake, so a cable release is a must! If you don’t have a socket for one, then you may have a problem. Whilst you can use the self timer to trigger the shutter, this will only allow the use of the camera’s longest shutter speed, and not the “B” setting if it has one.

In short, to make full use of every available shutter speed, it’s ideal to have a SLR camera that goes up to around 1/2000th or higher, and at the other end, has a “B” setting and some means of using a remote release.


In a nutshell.. that’s shutter speed and how it ties in with Aperture. Also, what speeds do what, and how to be a little creative with it.


Next up we’ll look at some semi-automatic camera modes that still allow you to adjust either aperture, or shutter speed.. but not both.

(coming soon)

 

I Can’t Be Arsed!


Ok... So that’s all the basics of exposure pretty much covered. Like most subjects however, that really is just the tip of the iceberg. It does give you enough to get started at using your camera manually, and the ability to understand how to create correct exposures reliably in varying conditions.

You’ve probably noticed though, that it can be time consuming: You have to meter, set the aperture, set the shutter speed etc. “What happens if I’m at a Formula 1 race? Surely I can’t be expected to do all that? I’ll miss the action” Well… yes and no. First of all, you can take an incident reading with a hand held meter, or a reflected reading with a grey card, and so long as the lighting conditions haven’t changed, it’s set, and there’s no reason to change it unless you change location. It is a valid point though: Using a camera in full manual mode is slow.

You’re not the only one to think this, which is why camera manufacturers provide semi-automatic modes for you.

Think back to the first sections of this tutorial: You’ll remember that any given EV can be made up from a combination of apertures and shutters speeds that you can work out using reciprocity law. You determine whether depth of field is the most important for you, or shutter speed, and set accordingly. Well, there are two modes on most cameras that do that:

Aperture Priority and Shutter Priority.

Small, consumer grade “point and shoot” cameras may not have either of these modes, but almost all SLR type cameras will. The difference between the two is pretty self explanatory:

Aperture priority allows you to set the aperture, and the camera will set a corresponding shutter speed. This is useful for portraits, landscapes and most situations where shutter speed is not important, but aperture is.

Shutter priority does the opposite: It will allow you to select a shutter speed, and the camera will select a corresponding aperture for you. This is useful where shutter speed is more important than depth of field, such as sports photography.

Remember though… rules are meant to be broken, but only by those that understand WHEN to break them. For a panning shot, it may be better to use aperture priority as you WANT a slower speed. There’s always an exception to every rule, but if you need to work fast, using either of these semi-automatic modes allows you to retain control over the aspect that’s most important: Aperture, or shutter speed.

These modes may be denoted by a range of symbols or acronyms. The most common are:

Nikon – A = Aperture Priority S = Shutter priority
Canon – AV =Aperture Priority TV = Shutter priority.

If your camera has neither of these, then you're stuck with fully automatic program modes... Booooo! Start thinking about upgrading to a more serious camera at some point. In the meantime, there's still a way to sort of have some control... sort of.. See those little symbols? That picture of a mountain for instance? That's a landscape mode, and will force the camera to use the smallest aperture it can for great depth of field. See the picture of a persons head? That's portrait mode, and this will force the camera to use the widest aperture it can for least depth of field. See the symbol of the running man? This will use the fastest shutter speed it can. These are all fully automatic controls that offer no refinement whatsoever, but if it's all you have, then at least you know that if a shallow DOF is what you're after, what mode will give you the best chance. It's still not offering you any manual exposure control in the true sense.

My advice is to buy a SLR camera with manual control as soon as possible.

Most cameras also provide program modes that are effectively fully automatic (see above paragraph). If you’re just after taking snapshots, these can be useful, but if you’re reading this, then you probably want to improve your skills, so avoid these.

To sum up: Full manual should be used for subjects that allow you to take your time, and think things through. Landscape, static subjects, portraits etc. Aperture or Shutter priority modes should be used for when you need to work fast, but need control over at least one of the parameters.




Why a SLR?

Simple. SLR stands for single lens reflex. It's a system that allows you to look through the same lens that takes the photograph, rather than a separate viewfinder. This means that what you see, is what you get (in terms of framing the shot). Very high end pro cameras will show 100% of the frame, but cheaper cameras will show around 92%, but this is still enough to accurately frame a shot.

Here's a diagram to explain



That mirror is usually in the down position you see above. This directs the image being focused by the lens onto the focusing screen, then through the prism to the eyepiece. WHen you press the shutter, the mirror flips out of the way and the very same image is then focused upon the film. The mirror flips back down. All this happens in a fraction of a second, and even with your eye to the camera you barely see the viewfinder go dark.

ALso, exposure information will relayed to you in the viewfinder so you wont have to take your eyes away from the camera.

THey also allow you to change lenses to give you even more flexibility and scope when it comes to creating the exact shot you need.

Coming Soon: Flash - How, Why, When, Where.

 

So.. you’ve got your shiny new digital SLR, and it does all the things you ever wanted it to do, and it even has a flash so you can take photos at night right?

Wrong.

On camera flash is the work of the devil!

I’ll explain why.

The least flattering light source is a small, hard light source place directly behind the camera, or on the camera itself. It does two things: Casts hard, unflattering shadows, and makes an image look flat. But there is another reason why on camera flash is a poor light source.

Inverse Square Law!

Oh God… another law, and more maths? Afraid so, but stick with it, because once you understand this, you’ll probably never use on camera flash again unless it’s just for a snap shot at a party etc.

To understand this fully, you have to get your head around the fact that light is just another form of radiation, like heat, radio waves etc. In fact, it’s all part of the same thing: The Electro-Magnetic spectrum.

I won’t put you to sleep with the actual formula but to sum up Inverse Square Law says:

The intensity of light radiating from a point source is inversely proportional to the square of the distance from the source. Got that? No? This may help.



So as you can see, with a point light source, if you double the distance, you quarter the intensity. In short, if you take a photo of someone 4 feet away, and 4 feet behind them is a wall, then the wall will be 4 stops under-exposed even though it’s only a further 4 feet back. This is why your flash shots taken at parties and night clubs where it’s dark, always have black, or very dark backgrounds. By the time the light has reached the objects behind it’s fallen off so badly it’s no longer sufficient to give a decent exposure.

Well.. the sun is also a point light source, so how come I don’t get black backgrounds during the day? That’s because the sun is 93 million miles away… the difference between you and the background can be measured in feet, so when the light has already traveled 93 million miles, a few more feet makes no difference. Look at the above diagram: It’s the density of the lines of radiation that determines intensity, so the nearer you are, the greater the fall-off. Look at the diagram again. Twice as far is ¼ intensity, but twice as far again is not 8 times less… it’s 6.. twice as far again will not be 16, it will be 12 and so on. The further away, the less the difference. It’s INVERSELY proportional to the square of the distance.

Even if the maths baffles you… just remember this. The nearer you are to the light source, the greater the fall off.

So what does this mean in reality? As usual, I’ve used props that are within arm’s reach to demonstrate




Shot 1 is taken with on-camera flash. Shot 2 is taken with daylight from a window. Both Homers were placed on the same piece of white paper.

You can clearly see Inverse Square Law in action. In the flash shot, even though the distance from front to back is only a few inches you can see the light falling off towards the back of the paper. The daylight shot doesn’t suffer noticeably from this, because 1) the window is a larger light source (in my case about 4ft by 5ft) and 2) it’s further away. This is why a professional photo studio will use umbrellas or big soft boxes on the lights – to make them larger. They will also use much more powerful lights that allow you to place them further away.

Remember, the further away, and larger the light source, the less the fall off in intensity with distance.

Shadows are also a problem with small lights near the camera. Because the light is radiating out from a single point (the camera) shadows are cast almost equally in all directions, so you get deep, unflattering shadows everywhere.

So… how can we cure this.

Firstly, at night, try not using flash at all. Place the camera on a tripod and use the available light (see above section on shutter speed).

A tripod is essential for this as you would imagine, and a decent tripod is something anyone who’s even remotely interested in photography should invest in. Decent pods start at around £50 or so. Manfrotto make very good pods, and I’ve always used them.

Using long exposures at night, also retains the “quality” of the illumination… the very thing that makes it look like night time. The shadows, lighting angles, the differences in colours of light. All these things make a night shot look like a night shot. Using flash will remove all of these qualities. At night, unless your subject is moving of course, don’t use flash. Use a tripod instead. If your subject IS moving of course, then that’s a different story. More on that further down.

Bounce!

Ok.. so on-camera flash is rubbish. What about flash guns that attach to the camera separately? Well.. because they’re further away from the camera (if only by a few inches) they aren’t so bad, but on the whole, the quality of light will be the same. There is one major advantage to most separate flash guns however: The can rotate and swivel. The reason they do this, is so you can bounce flash off another surface.

Look at the shot below.



This was taken with a separate flash gun mounted on the camera, BUT.. it was rotated so that it was bouncing off a white wall to my left and slightly behind. The differences are amazing. Why is this? Because the flash was not lighting the subject directly, but instead bouncing off the wall – the WALL was now the light source, NOT the flash directly. The wall is MUCH larger, and MUCH further away, so Inverse Square Law will tell us that fall off from front to back is MUCH less.

One other quality of large light sources is the softness of shadows, or Diffusion of the light. The Homer shot taken with on-camera flash has very hard shadows, where as the other two have very soft shadows. This is why on a cloudy day you cast no shadow upon the ground. The entire sky is one huge light source, so light is coming in from all directions. On a sunny day, the light is coming from only place – the sun itself, which is a single point in the sky.

Summary:

Small lights (flash guns or on-camera flash) produce hard shadows.
Small lights (flash guns or on-camera flash) suffer from fall off in light if close by.

Large lights (flash bounced off walls, or diffused daylight) cast very soft shadows
Large lights (flash bounced off walls, or diffused daylight) suffer less from Inverse Square Law, so fall off less.


Movement, darkness, and flash.

All the above advice is great if it’s a city scape, or a car that’s parked, because nothings moving. But what if you want to capture a moving object?

That depends on what you want to create. Remember the panning shots in the shutter speed section? That was a demonstration of how blur can create an impression of movement. In a city scape at night, you will have all seen trails of light created by traffic, so sometimes movement can be beneficial to a shot.

If you want to render a moving object sharp, but still use the available light to avoid the dark backgrounds, then you can combine flash with a slow shutter speed.

Most cameras, if left in full auto mode, will use just the flash to expose the shot, resulting in the kind of quality you get with the flash lit Homer shot above. You can however, use a slow shutter speed, and then fire a burst of flash as well. Most decent SLRs will allow you to manually set a slow speed, and still fire the flash.

The results look like this.


Image Copyright davedeluria

The ambient light has registered on the background to avoid a black backdrop, the slow shutter speed has registered the flames of the torches as streaks, and the burst of flash has rendered the man sharp.

Experiment with your flash is my advice. Use it in conjunction with a range of shutter speeds at night, and see what effects you can get. You’ll be amazed by what you can achieve by simply taking some manual control back from your camera when you use flash.

Daylight Flash?

You’ve probably see photographers using flash during the day, so what’s that about?

The answer, or rather the reason they do this, is shadows. During a bright, sunny day, there’s loads of light, so usually, no flash required. However, on sunny days, ironically, is when you should The reason is contrast. You may recall at the end of the Light Meter section, I put in a little caveat about excess contrast (scroll up and refresh your memory). Using flash during the day can “fill in” these shadows, and therefore reduce contrast.

Look at these two daylight shots.





Shot one has no flash to fill in, but shot 2 does. Far more detail has been rendered in the shadows, and therefore more flattering to the subjects.

The difference is obvious.

So go and play with flash, but remember, avoid using the on-camera flash directly as the main light. Use it to fill-in only, or don’t use it at all.

NB: Most SLRs have a maximum shutter speed that can sync with a flash. This is commonly 1/125th. Some cameras go up to 1/250th with flash, and some very high end cameras will allow much higher speeds with dedicated flash guns. A good rule of thumb if you're not sure is 1/125th as a maximum shutter speed to use with flash. In auto modes, the camera will sort this out for you, but even in manual modes most modern cameras will limit the top speed you can use when the flash is activated, or attached. If in doubt, stick to 1/125th until you've read your manual.

More Coming Soon.

 

All of the above is useless!

.....unless you now start to think in a different way.


So... That's enough theory to ensure that you can take, sharp, well exposed, technically correct photographs. Does that make them good? Errrr..... no.


Camera's don't take photographs: People do.

There is no escaping this fact, which is why I love to laugh at people who spend obscene amounts of money of camera gear they don't need. It will NOT help you take a better photograph. Upgrading from a £30 point and shoot to a proper SLR will, but other than that, upgrading from a Canon 350D to a Nikon D3 will not do anything for your pictures. They'll be higher res because of the Nikon's chip, but other than that, if you took crap images with your £300 camera, you're still going to with your £3000 camera.


Here's a picture of a car.




Here's another picture of a car.




Which do you prefer?



Of course.


So seeing as the first picture is well exposed, sharp, and technically correct, why is the second one so much better?



I'll break it down in to separate points as I see it.

1. Camera angle.

One of the most common mistakes beginners make is to shoot everything from their eye point. If you're a 6ft tall man, then all your photographs are taken from the perspective of a 6ft tall man regardless of what you're taking. Small child? taken from 6ft... elephant? 6ft... car? 6ft..... BORING!!!!

THINK about different viewpoints.. TRY different viewpoints. Often what makes a photograph interesting is the very fact that you're showing something from an angle, or in a way that one doesn't see everyday. Getting down low, or using a tilted angle where most would use a straight one. From far away with a long lens, or very close with a wide one.

Literally looking at things from a different perspective often makes the difference between a "snap shot" and a really interesting photo.

2. Lighting

The first photo is dull. It's a flat, dull, grey day. This is fine if you just need to take a record of something, but if you're taking a photo of your pride and joy, why pick such a miserable, uninteresting day? This is particularly true of cars where the lines, curves and form is so important to show a car off.

There's a pretty good rule of thumb with natural light, and that's that mid-day sun and overcast days usually make for crap shots. Dull days lower contrast too much resulting in a flat, lack-lustre feel, and mid day sunlight is too contrasty resulting in harsh shadows.

Usually, when working available light outdoors, evening sunlight gives the most interesting results. The low angle is more flattering. Shadows are lessened, but still there to give modeling, and the warmer colour of the light often makes it more appealing.

3. Backgrounds.

The first shot is boring because the background does nothing to enhance the car. It's just some bushes. They're not particularly interesting and they're doing nothing to draw your attention to the car.

That road sign poking out of the bonnet also ruins the shot as you end up trying to read it. It's a distraction.

That bit of road marking bottom left... distraction!

Look around the viewfinder! Don't just look at the object you're photographing. We've all seen shots with trees sticking out of heads? Good... think about this seriously before you press the shutter. Is there ANYTHING there that shouldn't be. Often, just moving a few feet will dramatically improve a shot.

This is why I advocate the use of a tripod: It slows you down, and makes you take your time.


4. Lens Choice (or zoom length)

A standard lens, or setting your zoom range in the middle is often quite dull. Again, as with camera position, using a zoom length or lens that gives a natural perspective can be uninteresting because that's how we see day in, day out. Make things unusual. The second shot uses a very long lens with the car far away to "flatten" perspective and blur the foreground. It's also easier to isolate a subject by zooming in on a neutral piece of background.

You can exaggerate, or play down features with the right choice of lens as well.

Want to exaggerate a car's features? Think about lenses.

The Mustang is best known for it's long bonnet/short cabin shape... so if you were to take a photo that shows that, why not go close with a short lens (or zoomed out) like this?



Want to show a car's profile? Then the second Mercedes shot is a perfect example. Long lens, far away, neutral background. Also, the photographer got down to teh car's level, and didn't take the shot from a standing position.



Basically, NEVER just put a camera to your eye. Squat down, climb a wall.. anything... but never just put it to your eye and "click".

Think about backgrounds. Look around the viewfinder. Remove anything distracting.

Come back later if the light is poor.

Think about lens choice.


Finally, the hardest thing to learn, is the story... the feel. What are you trying to say?

Using the S-Class as an example, which of the following shots "speaks" of what the s-class is about best?

This one?




or this one?



Why? Both are technically OK... neither shot is breathtaking in any particular way. What separates them is that one is a snapshot, and the other is considered. The S-Class is an executive saloon. Placing it in front of a really impressive house or building speaks of opulence, power, wealth... it SUITS the car. Taking it in a car park? Nah... doesn't really do the car any favors does it?

As usual though, breaking the rules can work, but you have to know HOW to break them. Juxtaposing an S-Class against a really, really run down area may work also, as it enhances how luxurious the car is, but be careful... you're into the world of semiotics and signs here... it can also make the s-class appear to be a gang land drug dealers choice of vehicle... which is why you'll probably never see a Mercedes ad like that. It may look cool, but what is it SAYING?

So think about story.

Which of these shots of a Range Rover is right do you think? Both are technically sound... but which one speaks of the car more?

This one?




or this one?




Neither of these shots are particularly great, and that's why I've chosen them. They're both pretty uninspiring, but which speak of Range Rover more?

It's a large 4x4 from a company that has a proven track record of making quality, off road vehicles that offer luxury, so the second one seems to just be "right".

Having said that, stick some bling rims on it, and then all of a sudden, THIS setting suits it more.



Again, not the best photograph, but the setting, lighting, and mood suits the car.

Now think about all of this a minute.



What makes this shot so much better than the other Range Rover shots?

It's combining all of the things we've discussed so far in this tutorial.

1.Setting and background... perfect for the story we're trying to tell

2. Quality of light perfect... warm, evening light to give good, but not excessive contrast and nice colour, modeling. The photographer has also cleverly used the fact that the car is in shadow and therefore cooler in colour compared to the warm evening sun on the mountain tops.

3. Good lens choice to give a sense of open space.

4. Low angle to add drama

5. Well metered, well exposed.

6. Good depth of field (as the background is part of teh story here... it needs to be sharp)

7. It speaks of what a Range Rover is about. Freedom (4x4), luxury (exotic alpine location), etc

In short, choose locations carefully. Look around the viewfinder to make sure there's nothing there that shouldn't be. Think about the story.


Lastly, composition.

There are no "rules" as such, but one rule that often leads to a pleasing composition is the "rule of thirds".

imagine your viewfinder was split into a grid of nine squares like this.



Placing a point of interest on an intersection of lines usually works best.

for example, with the wide shot of the range rover, you'll notice teh car is on a third.



With very close shots this is more difficult, but ensure something of interest is on a third and it usually works.


These are all just a few pointers. There is SO much more to photography that I could make this thread 500 posts long, but A) you'd never read it all, and B) All I intend to do here is get you interested enough to go learn more yourselves!

If you've read through this tutorial to this point, then you're probably interested enough to want to do that anyway... in which case Google is your friend

I may add to this more if people request anything specific, but I feel you have enough here to set you on the right track.

Now get out there and start shooting!!!

 

Sorry for digging this thread up again, but I wanted to say that it's an awesome entry intro to photography, and if it had of been around when I was still learning the basics it would have been a great starter read.

In fact I know someone who is just getting a DSLR this week, so will show them this (I did try to explain it to them, but this is put across much better).

Thanks for taking the time out to write it all.

Dan

 

You're very welcome

 

Finally I found this forum...I like photography..This is a nice photography handbook by John Hedgecoe, 3rd edition. thanks for that!!!