Bet some of you are thinking “Photography for wargamers, eh? Quite pretentious of you, laddie, considering the quality of some of the pictures on your blog! Also, hadn’t that done been before?!”.
Well, sure… but it hadn’t been done by me yet and considering how frequency of my wargaming activities have decreased to another low watermark, I do what I have to do to keep this blog alive.
Seriously though… I’ve been toying with the idea of writing a couple of posts about this topic for quite a while. You see, wargaming is what actually got me into photography in the first place and the specific challenges of taking photos of wargames is what shaped my ‘development’ in photography department. Along the way, I’ve made (and keep making) a lot of mistakes, but I’ve also learned a couple of things while having a blast with cameras (most of the time). So, if I can help somebody to avoid some of the pitfalls I’ve encountered and maybe tell something informative about this particular aspect of our hobby, I’ll consider it effort well spent.
Before we continue, couple of usual disclaimers. First and foremost, I am not an expert of any kind, so keep that in mind. I may be mistaken in my definitions, terms or explanations. Second – once we get so far and if I at any time describe some technique – it may work for me, but doesn’t necessarily have to work for you. As always on this blog, YMMV principle is in effect!
Allright, let’s get on with it then. I will approach this subject from an absolute beginner’s perspective, so let’s start off with the basics of photography and digital cameras.
Basic principles
What a photo camera does is really pretty simple – it’s a dark box with a sensor of some kind that catches light and registers it on some type of medium. In old days, it was a film coated with light sensitive chemicals. These days, photography has become digital affair and the light is caught by a light sensitive sensor, transferred into zeros and ones and stored on a memory card.
From a photographer’s perspective, there are two factors that need to be controlled – how much light to allow into the camera and for how long to catch the light. Both these factors are controlled by something called the shutter. Shutter is the “gate”, located either in the camera itself or in the lens, that separates the outside world from the light-sensitive sensor. When you make a photo, this gate opens to a certain degree and for certain amount of time.
Aperture is the term used for the hole that appears when the shutter is opened. Aperture is the first of thee fundamental factors in digital photography. In the picture above you can see different apertures for a specific lens. The shutter opens in pre-defined incremental steps, called f-stops. The lower the number of the f-stop, the bigger the hole.
The aperture controls one thing – how much light is allowed into the camera to be registered by the sensor. In simplest possible terms, the bigger the hole, the more light is let in. This reduces the time needed for the sensor to register the image. But that’s just the part of the truth; size of aperture affects the image in other ways. We’ll get to it in a while.
Shutter speed is term used to describe the amount of time that the shutter is opened to allow the light into the camera. It’s the second of the factors that you need to decide upon whenever you take a picture. The longer the shutter is opened, the more time you allow for the sensor to register the light. The relation between aperture and shutter speed is simple – the smaller the opening, the more time your sensor will need to register adequate amount of light.
In picture above the f/1.8 opens the shutter wide open. This usually means that you can keep your shutter opened for very short while, usually a miniscule fraction of a second. On the other hand f/11 aperture barely opens the shutter. This makes it necessary to keep it opened for significantly longer time, sometimes several seconds.
ISO is the third and final factor that needs to be controled when taking pictures. Unlike aperture – the size of a hole in your camera – and shutter speed – the time the hole is opened – ISO is a bit more abstract in its nature. Basically, it’s the setting that controls the sensitivity of sensor in your camera to the light. ISO typically starts somewhere around 100 and goes up in predefined increments up to its maximum sensitivity setting. The higher the ISO setting, the more sensitive your camera sensor becomes.
These three factors are directly related to each other. Together they form so called exposure triangle. Put these three together and here’s what you get:
- Shutter speed – the shorter the shutter speed, the bigger aperture needs to be and/or the more sensitive your ISO settings needs to be. The longer your shutter speed is, the more you can reduce your aperture and reduce ISO sensitivity of your sensor.
- Aperture – the wider aperture (smaller f-stop number), the shorter time is required for your shutter to be opened and/or your ISO sensitivity needs to be. Small aperture requires for your shutter to be opened for longer time and/or your ISO needs to be increased.
- ISO setting – low ISO setting will increase the amount of time your shutter is opened and/or for your aperture to be set to ‘bigger hole’.
Zero sum game
Pretty simple, eh? But what does it have to do with anything? Well, consider for a moment the most common problems with photos:
- They are either too dark or to bleak.
- Photos are blurry.
- Only part of the photo is in focus.
- There is a lot of strange inaccuracies, like small spots, all over the image.
Problem no. 1 is caused by either too little or too much light hitting your sensor.
Too much light will result an ‘overexposed’ image – the sensor will be overloaded with the light and register either too much light or, even worse, reach to its maximum sensitivity, resulting in homogenous blobs of color without any detail.
The opposite happens when too little light reaches the sensor. That’s caused by too short shutter speed, to small aperture (too high f-stop for selected shutter speed) or too low ISO sensitivity for selected shutter speed/aperture combination.
When a photo is ‘good’, the shutter speed is adjusted to right time for your ‘opened hole’ (aperture) and current setting for light sensitivity for the sensor in the camera.
Problem no. 2 is easier to explain – your shutter time is so long that your hand shakings or vibrations disturb the camera to such degree that its movement is registered in the image. Some folks have a so called ‘steady hand’, personally I seem to have a hand of an alcoholic in the middle of withdrawal. Any shutter speed above 1/250 of a second will result in blurry image if I hold the camera!
To counter this problem, increase the aperture (lower f-stop number) or increase ISO setting.
Problem no. 3 can be caused by your camera focusing on wrong spot. More probably though, your field of depth is too short. What’s field of depth, you ask? Well, it’s the distance from your initial focus point that remains sharp and in focus. Consider your own eye. When you read, you see clearly the text you focus on and maybe a bit around it. Rest of the page is ‘out of focus’. Depth of field in a camera works the same way. And it’s controlled by your aperture – the bigger the hole (smaller f-stop number), the smaller amount of image will be in perfect focus!
I’ll be talking about field of depth a lot more later on, so ponder the consequences of this behavior for a second and let’s move on.
Finally, problem 4. Daddy of this one is your ISO setting. Basically, the more sensitive your sensor becomes (higher ISO setting) the crappier it becomes at understanding what colors look like.
Conclusion
If we put things together, here’s what you get. Perfect picture is correctly exposed, with sharp focus on stuff we want to take a photo of and with correct reproduction of colors. Easiest way to get a sharp photo is to keep shutter speed as low as possible. But that demands that aperture is wide open and that reduces the distance in which things are sharp and in focus. Quite often, the physical limitations of the camera lens itself can be the limiting factor – its shutter cannot be opened wide enough and we need to accept longer shutter speed than we’d wish for. Of course, we could increase the ISO sensitivity of the sensor. But that may make the photo grainy and (worst case scenario) covered with mis-colored dots.
OK, so let’s keep the ‘hole’ small. This will increase shutter speed, resulting in blury photos. Fine then, let’s push ISO to the maximum settings… oh damn, these mis-colored dots are there again!
So… you now think ‘Is he saying that there is no way to take a good picture?’. Well, kind of… actually, taking a good picture under good lighting conditions can be a no-brainer. But it’s when things aren’t working so great in the lighting department that it can be quite valuable to be able to figure out what causes the problem and maybe figure out a work-around.
But we get there in next installment of this series.
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