a1 Photo Tips

In case you are new to photography, you may feel it is convenient to just put your digital camera on automatic and hope for the best.

If you do, I bet you will soon get a bit frustrated with how your pictures often don’t come out the way you intended, and you sit there wondering what’s going on.

OK, then it is time to take the first steps toward having control over the camera - as opposed to having the camera control YOU!

Take the clown picture here for example. Imagine how dull it would have been if you had taken the picture using automatic settings. The camera would then have fired the built-in flash unit and ruined the mood of the event (and you may also have gotten thrown out for disturbing the act!).

On the contrary, the photographer here had total creative control. He took the picture using the ambient light, and used a very long exposure time. And, yes, the result was motion blur.

However, what do you feel when you see that “blurry” photograph? Personally, I feel it is a great shot! And you could never make a picture like this unless you had creative control over your camera.

The Exposure Triangle

To begin with, there are basically THREE WAYS you can control how the image is exposed in the camera when you press the shutter. You can think of these as the three tips of a triangle; the Exposure Triangle.

1. Exposure Time = Shutter Speed

2. Aperture = Size of Light Opening

3. ISO Setting = Sensor-sensitivity

The exposure time, also known as “shutter speed”, determines how long time the camera sensor is exposed to the light from the subject of interest. Long exposure is another word for slow shutter speed.

The aperture setting determines how big the opening is allowed to be, for the light coming in. And remember that the larger the aperture opening, the lower the number on the aperture scale. Expensive camera lenses usually allow the use of larger apertures, making it easier to work with them in low light.

Finally, the ISO setting determines how high you crank up the light sensitivity of the sensor unit in the camera - the part that transfers incoming light to an electronically stored image. Higher sensitivity means more “noise” in the image. To get the best quality you usually set this to 50 or 100 ISO units.

So, a few words on shutter speed. Generally, if nothing you’re trying to capture is moving much you can use shutter speeds down to maybe 1/60 of a second. With practise, you can use even slower shutter speeds, ie. longer exposures, for non-moving subjects. In case you want to freeze movement, you need a faster shutter speed. For instance, a car driving past you and going fast may require a shutter speed of 1/500 of a second to “freeze” its movement.

The picture of the surfer here was shot at a very fast shutter speed, to “freeze” the movement. Fast movement = fast shutter speed.

To get creative control over the shutter speed point of the Exposure Triangle, you need to consider how you want to use that setting to control the mood of the image. Like, do you PREFER to “freeze” the movement by using a fast shutter speed, or would you rather experiment with a very slow shutter speed to get intentional motion blur, as in the clown picture?

In the case of the clown picture, the low ambient light wouldn’t allow a very fast shutter speed - and neither would it be needed or even desirable in that situation. Conversely, in the surfer photo the light was quite strong which allowed the photographer to snap the picture at a fast shutter speed - likely 1/500 of a second or even faster.

You could have made a very different surfer picture by using a slower shutter speed, to create some motion blur. Then you would have needed to adjust the two other points of the Exposure Triangle accordingly - smaller aperture and/or lower ISO setting, to avoid over-exposing the image.

In conclusion: You use the shutter speed point of the Exposure Triangle to control how you render movement in an image. If the rendering of movement - either by “freezing” it or by using motion blur - is a top priority in a particular situation, then your first priority is to adjust the shutter speed to a setting that fits your intention. The other two settings (aperture and ISO) will take the back seat, so to speak. You simply set them to whatever is needed to get a correct exposure.

Photo credits: clown: Ctd 2005, surfer: abnelphoto.com

If you are at all like me, you will many times have been frustrated with your pictures coming out un-sharp! This problem can have many sources, and I will try to cover the most common ones in this article.

1. Too Long Exposure Time

When shooting in low light, like in deep shade or near sunset, the light may be so low that the camera needs to use a long exposure time, ie. a slow shutter speed, to pass enough light into the camera to create a clear image.

The result may be that you, or the subject, or both, move slightly during the exposure - creating some blurriness. If everything is unsharp, it was likely you that moved, and if the background is sharp while the subject is kind of hazy - assuming it is something likely to move, like a person or an animal - it was they that moved.

What to do? Make sure you use a shorter exposure. If possible, you can compensate for the shorter exposure time by simply using a larger aperture (which creates a larger opening into the camera to let more light in).

One other thing you can easily do, besides using a larger aperture setting if possible (larger aperture openings have lower numbers on the scale) - is changing the ISO setting on the camera. If you change that setting to a higher number, for instance from “100″ to “400″, it means you increase the sensitivity of the camera sensor to incoming light.

The drawback is that the quality of the picture will be somewhat impaired - there will be more “noise” in the image, which is increasingly evident the larger you make the final picture. However, in some situations you may live with that in order to get a shorter exposure time.

The simple operation of increasing the ISO setting is the modern equivalent of changing to a film with higher sensitivity (a “faster” film) in the old roll film cameras. In these silver-based films, a higher sensitivity meant a film with coarser grain.

Another obvious remedy is to use flash. Now, there are problems with using flash: it tends to destroy the “mood” of the scene and also it only works at short distances (I have seen ridiculous things like people making snapshots of fireworks with the flash unit turned on!). Besides, in some situations you are not even allowed to use flash. Still, it is unfortunately the typical way most people deal with any low-light situation.

Digital cameras may even be pre-set to automatically fire off the built-in flash unit as soon as the light gets low, by default. And the result tends to be a sharp, but very ugly, image. Professional photographers use flash all the time, but in a very sophisticated manner; and I guess if you are one of those you are not reading this anyway - so I won’t try to get into that subject here.

Conclusion: simply firing off the built-in flash unit that comes with every camera is usually not a good solution to the problem of blurriness caused by too long exposure time in low light, in my humble opinion. Instead, try to gain a shorter exposure time by using a larger aperture and/or change to a higher ISO setting.

If all else fails, you can of course stick with a long exposure time, AND use a tripod. This works if your subject doesn’t move and you have the time to get your tripod set up in the position you want. Actually, I have seen very interesting pictures made in low light, by simply placing the camera on the ground or some other solid surface; so don’t despair if you don’t have a tripod or you left it at home because it was so clumsy!

If you snap a picture of something that moves very fast, like a speeding car or a speeding fish, you need to either use a VERY short exposure (like 1/500 of a second), or you pan with the subject - meaning you follow it in the viewfinder and make sure you keep it there while pressing the shutter. Using this method with some skill, you can make very interesting pictures where the subject is rendered sharp but the background is blurred.

2. Incorrect Focus

A different cause of unwanted blurriness in your photos is when there is focus - but in the wrong place! For instance, you take a close-up of a friend standing in front of a building and it then turns out the building is nice and sharp but your friend is blurry.

Usually, this is because the automatic focus mechanism in modern cameras assumes that whatever is at the center of the image in the viewfinder is the most important part of the scene. And if you placed your friend off-center to make the composition more interesting (as discussed in the Rule of Thirds article), then the building ends up in the center of the picture and of course the camera then puts the focus there also!

Remedy: you must anticipate this problem and avoid it by pre-focusing. What that means is: you first place your friend in the center of the viewfinder, and let the camera focus on him/her. Next, you lock the focus before switching to the placement you actually want, with your friend off-center.

So how do you lock the focus? Well, in my experience it is usually done by pressing the shutter half-way down - not enough to snap the picture but enough to engage the focus lock. Please read the manual that came with your camera to make sure how it works in your case. (Reading the manual is ALWAYS a good idea!)

A different variety of this problem is when you try to focus at a shorter distance than the camera can actually handle. On most digicams, there is a special setting you can use when trying to get nice snapshots of snails, butterflies and such critters. Or flowers - the closeup setting is usually indicated with a tulip-like symbol.

3. Other Causes of Poor Sharpness

There are of course other ways you can end up with blurriness in your digicam pictures. For instance, there may simply be dirt on the front lens. Be very careful when wiping off such dirt, or you may scratch the delicate surface of the lens.

And, there may be some technical problem with the camera. For instance, my old Canon digicam seems to have contracted a case of nearsightedness nowadays. Pictures taken at short distances are quite sharp, but everything at a longer distance is rendered slightly out of focus. It gets better if I use the smallest aperture (since the depth of focus increases at small apertures), but by and large I just have to live with this until I can afford to replace the camera.

Photo credits: flower picture by *Micky; ray picture by jurvetson

Help, the house is falling! No, actually it isn’t falling at all. It is all my fault it looks like this, I was trying to get an interesting angle on this nice old house but the result was a bit awkward.

What is the problem here? Well, we know that buildings usually are standing straight up, and exceptions are so rare they even become famous (such as the leaning tower of Pisa, Italy). Here it looks like the house is standing on a sloping surface, which it certainly is not in real life.

A problem like this can often be corrected in the virtual darkroom, ie. using image editing software like Adobe Photoshop. However, when you rotate the image to correct those sloping lines you are then also forced to trim it down to get the edges of the picture straight - meaning you crop out some of the picture’s content.

Here is the result of the operation in this case. Note that a piece of the roof is now cut off, because of the cropping I had to to after rotating the original image by four degrees. And the perspective still looks a little bit awkward.

I could have avoided these problems by being more careful in choosing the angle for my picture, when I had the opportunity.

Making good pictures of things like buildings, that usually have very straight and perpendicular lines, isn’t that easy. One problem is making sure it stands straight on the ground; then the next issue is that the building tends to be much taller than you - which means you need to point the camera up rather than straight ahead, if you want to include the upper part of the structure. The result is that it seems to be narrowing toward the top! (This effect is also visible in the picture above.)

There are now advanced image editing functions available in software like Photoshop, which can rather successfully correct such problems. And in certain cases, you may even prefer to keep the effect as it is. Although we know that houses are usually not narrowing toward the top, it actually appears that way to our naked eye. Therefore, a picture showing this perspective effect can be acceptable in some contexts.

Now over to a related issue: getting the horizon horizontal. If the horizon isn’t shown as perfectly horizontal, ie. parallell to the top edge of the picture, it feels as if the whole world is falling!

This is especially true if the horizon is where water meets the sky. We know the ocean (or lake) isn’t sloping, and since this line is so VERY straight, we are also very sensitive to any aberrations.

Imagine for instance a brochure advertising trips to sunny places like this one - and the horizon is not horizontal in the illustrations! Do you think people would buy those trips? Probably not, if they got seasick just by looking at the pictures…

After saying all this about keeping things straight, I must add that there are situations when you can break such rules - if you know what you’re doing.

For example, pictures of speeding cars or motorcycles often display a dramatically tilted horizon line - and this is done on purpose, to emphasize the feeling of speed and drama.