I was preparing notes for recording a Chit Chat Across the Pond segment on this topic with Allison this evening, and it occurred to me that this would make a good blog post, so I stopped making bullet points and wrote this article instead.

I still remember very vividly the first time I held my first DSLR. I was shocked by how many knobs and buttons there were, and I was very intimidated by all that apparent complexity. The appeal of the “auto” setting was very strong, and for weeks that’s where my camera stayed. The thing is, using a DSLR on full auto is such a waste, why get a camera that gives you so much artistic control, just to surrender it all to the camera’s primitive intelligence?

Today my DSLR is never in Auto, it spends a lot of time in ‘A’ mode (‘Aperture Priority’, TOTALLY different to Auto), and quite a bit in ‘M’ mode (full manual). Being the master of your camera in full manual mode is very liberating, and opens up a lot of creative possibilities. So, how do you get from Auto to Manual?

I’m going to propose what I think is a safe and un-scary path from Auto to Manual, but before I start on that, we really do need to look at some real basics.

Ultimately, photography is about getting enough light onto a light-sensitive material to make an image. How you get that light there has huge effects on the look of the image, but ultimately, you need to get the right amount of light onto that light-sensitive surface. In the past the light sensitive surface was a chemically coated piece of glass or film, now it’s a digital sensor. The material has changed, but the concept hasn’t.

Firstly, how much light you need depends on how sensitive the material is. If it’s not very sensitive, you need a lot of light, and the more sensitive it is, the less light you need. We measure the sensitivity of photographic materials using something now called ISO (it was called ASA before). Typical film values these days are 200ISO or 400ISO, and digital camera sensors have so-called native sensitivities of about 100ISO or 200ISO. Modern digital cameras can cheat though, they can multiply the light they get to simulate higher ISOs than their base ISO, but that ability comes at a price, the more you push the ISO, the more noise you get. You’ll always get the cleanest image at your camera’s native ISO setting, sp you need to know what it is for your particular DSLR (it’ll be in the manual, as well as on the internet).

So, the sensitivity or ISO determines how much light you need, but how do you control how much light gets in? For this you have two controls, the most obvious one is the so-called Exposure, or Shutter Speed. This is simply the amount of time that light is let hit the light sensitive material. We usually measure the exposure in inverse seconds. This is confusing, but it does make some sense. An exposure of 500 is one 500th of a second. An exposure of 200 is one 200th of a second. This is why you often see exposure as 1/500. If the exposure is longer than a second it will be written in seconds with a single dash afterwards, so three seconds will be 3′. Just like higher ISOs have the side-effect of more noise, the length of exposure time has side effects too. Really short exposures freeze action, while really long ones stretch it out, resulting in moving things being blurred. Artistically, you will want one or the other effect, so that will play into your choices.

Finally, you can control the Aperture of the camera. This is the size of the hole through which the light shines onto the sensor. A bigger hole means more light, a smaller one less. The confusing thing is that we don’t measure the Aperture in inches or mm or anything like that, we measure it using the “Focal Ratio” (written as f/n, e.g. f/8 pronounced ‘F eight’) of the lens. There are really good mathematical reasons for this, but I’m not going to go into those here. What I will say is that a small focal ratio means a big hole so a lot of light gets through, and a large focal ratio means a small hole, so much less light gets through. Just like ISO and Exposure, the Aperture has side-effects on the way the image looks. The wider the hole, i.e. the smaller the focal ratio, the less stuff is in focus (called a ‘shallow depth of field’), and the smaller the hole, the more stuff is in focus. Again, artistically this is very important. If you want a good portrait where the person is in focus, but not the background, you’ll want a low focal ratio, if you’re shooting a landscape and you want everything in focus you’ll need a high focal ratio. BTW, a focal ratio of f/1.4 would be a VERY wide aperture that only a really good lens could get to, and likewise f/64 would be a VERY small aperture that many lenses won’t get to.

So, putting it all together, the ISO determines how much light is needed to get a proper image, and the aperture and exposure combined determine how much light actually gets in. To get a properly exposed photo you need a combination of Aperture and Exposure that’s appropriate to the ISO. The fact that these three factors are linked means that you HAVE to make compromises. You can’t have low noise, a really deep depth of field and a really short exposure all at once because that means you need a lot of light but you don’t let much in, and the little you let in you only let in for a short time! Making the needed compromises IS the art of photography.

So, when your camera is on full auto your camera makes these compromises for you based on no other criteria than getting in enough light. Artistically, you have no control other than where you point the camera. Your portraits will have too much of the scene sharp, your landscapes too little. Your attempt at motion blur with a passing train won’t have enough blur, and your attempt at taking a picture of the kids playing sports will have too much. Basically, the camera has total artistic control, and no understanding at all of art! The result? Snapshots at best.

Clearly, going from this to having to think about everything yourself in one step would blow your brain and probably dishearten you so much that you’d just give up. So, lets start by taking just a little control, and gradually expanding that control till we’re completely in charge.

On the settings dial on your camera there will be a bunch of icons, probably a flower, a mountain, a face, a star, and a running man. These are modes that are still fully automatic, but they tell the camera what type of shot you’re taking, so it can make better decisions on your behalf. The flower mode is for closeup shots of things like flowers or butterflies, it’s often called the ‘macro’ mode. The running man is a ‘sport’ mode, this means the camera will keep the exposure short at all costs, opening the aperture and increasing the ISO to make that possible. The face is a ‘portrait’ mode, and will favor wide apertures (i.e. low focal ratios). The mountain is a ‘landscape’ mode, which will keep the aperture narrow (i.e. a high focal ratio) so that as much is in focus as possible, and it will increase the exposure to make that possible. Finally, the star is a night mode and it will jack the ISO right up and try to keep the exposure short.

Just making use of these icon modes will make a huge difference. The camera is still making all the decisions, and it will still make mistakes, but at least it now has a clue what exactly it is you’re trying to achieve, and can try to do the right thing!

The next step up is the so-called ‘program’ or ‘P’ mode. This is only marginally different to full auto, but depending on the camera model it will let you set some aspects of the settings yourself. Program mode will still blindly choose the Aperture and the Exposure, but it will let you choose things like the ISO and the white balance if you want to. Some people like working in P, but personally, I never saw the point. I’m always reminded of Scott Bourne’s two sayings about Program mode, the polite one. “P does not stand for perfect”, and the impolite one “P stands for piss-poor”.

Artistically, depending on the subject, you’ll either be worrying about the depth of field, or the exposure time, so you’ll be interested in taking direct control over the Aperture or the Exposure, while letting the other vary to get the right amount of light onto the sensor. This is what the ‘A’ (Aperture Priority) and ‘S’ (Shutter Priority) modes are all about. When you’re working in A or S mode can set the ISO yourself (though many cameras have an AUTO setting for ISO, so you don’t have to), as well as the White Balance (again, most cameras have an AUTO setting for white balance, so you don’t have to take control if you don’t want to).

So, which mode you use depends on what you’re photographing. The vast majority of the time it’s the depth of field (how much of the scene is in focus) that you really care about, so my camera spends about 90% of it’s life in ‘A’ mode. The nice thing with a DSLR is that you can see the results straight away, so you can experiment with the Aperture till you get a result you like. One tip I will give though, f/8 is a great starting point for when you’re not sure what to do. There’s an old saying in photography, “The two secrets to a good shot are f/8 and be there”. The one exception to that would be portraits where you really want to get as shallow a depth of field as you can, so you should start with the lowest focal ratio your lens will allow, and work up if needed. Some places are just too bright to get away with really low focal ratios because there is a limit to how short the exposure can be, and how insensitive the sensor can be.

S mode comes in handy when you’re playing with motion. If you want to get a smooth look from a waterfall you set as low a shutter speed as you can get away with. If you don’t have a tripod, a good metric is that the focal length of your lens in mm translated to inverse seconds is about as slow as you can go. At 18mm you can hand-hold about 1/18 of a second. At 200mm, only 1/200 of a second etc.. Another example would be either motion blur or pan blur. motion blur is when you hold the camera still and something moves through the frame and gets blurred, pan blur is when you move the camera to track a moving object and get it sharp, but everything else blurred. Finally, if you want to freeze action it’s really important that you take control of the shutter so you can be sure it’s fast enough not to get blur on the footballer, car, train, plane etc..

The vast majority of the time my camera is in either A or S mode. At a guess, I’d say 98% of the time in fact. However, sometimes you do want to take full control. I do this when I need to do do something very unusual like take pictures of stars, or when I need to be absolutely sure I get the perfect shot of a once-off event like a special train. What I do for special trains is get there before time, experiment with exposure and aperture settings till I get a perfect one, and then take the shot when the train comes. The reason I do this is because trains have bright headlamps, and those headlamps play tricks on the camera’s light meter, resulting in under exposed images on any of the automatic or partially automatic modes.

This brings me to the very last thing I want to talk about, the light meter that’s built into your DSLR. All the even mildly automatic modes depend on that light meter to make their calculations. All modern DSLRs have light meters built in, and they are set up to average the entire scene to a brightness value of 18% grey, that’s what the human eye considered properly exposed. However, light meters have no intelligence, and make EVERY scene 18% grey, even ones that aren’t. For example, a snow scene is much brighter than 18% grey, and a dusk scene, much darker. In these kinds of situations, you need to “bias” the light meter so it thinks something either brighter or darker than 18% grey is ‘right’. You’ll need to check your camera’s manual to find the button for it on your particular model, but on the Nikon D40 you hold down the ± button and rotate the thumbwheel to set it. In your manual the setting will probably be called either “Exposure Compensation” or “Exposure Bias”. The really important point is that you can only set the exposure compensation on the more manual modes. You can’t set it on full auto, and on most cameras you also can’t set it on the ‘icon’ modes. You can set it in Program mode though, as well as in Aperture Priority and Shutter Priority modes (it makes no sense in full manual mode, so you can’t set it there either).

If you do venture to full manual mode, most cameras will display the output of the light meter in the heads-up display in the viewfinder. This will help you see how you’re exposing the shot when you’re in that full manual mode.

So, that’s it, that’s my suggested route for getting away from using the full automatic mode on your DSLR. Don’t think you have to go all the way to the end of that route and start shooting everything on full manual though. If you get as far as Aperture Priority and Shutter Priority for most of your shots, you’ll be doing just fine. Those are the modes more accomplished photographers use most of the time.