Getting Started With Your DSLR Camera: 1 – First Things First

Introduction
The two principal factors that you have to understand to use the camera are:

  • Exposure
  • Focus

Even more important is composition, but that’s a whole other subject. Here, we’ll stick to getting familiar with the camera.

Exposure
There are three variables you need to consider to get the exposure right. Whilst it is true that you can correct a wrong exposure to some extent afterwards in the computer, you will get much better results by getting it right in the camera, so it is worth giving it some attention.

The three variables are:

ISO (pronounced eye-ess-oh, not eyezo!). This is the modern digital equivalent of film-speed and adjusts the sensitivity of the camera’s sensor to light. In general, you want to use the lowest ISO setting for the best quality image. Each camera has a native ISO at which it delivers the best quality, probably ISO 100. Higher ISO settings are useful for low light conditions or for fast-moving subjects, but image quality is compromised, though modern DSLRs can use remarkably high ISO settings satisfactorily. I recommend you use ISO 100 for most static objects.
Aperture – this is the size of the hole in the lens through which the light passes to strike the sensor- the larger the hole, the more light passes through. Aperture is measured in “f numbers”, sometimes called “f stops”. You need to remember that the larger the f number, eg f22, the smaller the aperture, and the less light gets through. Large apertures will have numbers like f2 or f1.8.
Shutter Speed – this determines how long the camera lets light through the aperture. In a DSLR, the shutter comprises two curtains that pass very quickly in front of the sensor, and the time between the passing of the two curtains is the shutter speed. Shutter speeds are measured in fractions of a second. A typical shutter speed might be 1/125 of a second. Faster shutter speeds, such as 1/400 are needed to capture moving subjects. If the shutter is only open for a short time, there is less likelihood of the subject moving during the exposure and becoming blurred. You might use very slow shutter speeds, perhaps 2 or 3 seconds, to intentionally blur a subject such as moving water, but in such cases you would have to use a tripod to hold the camera steady and a remote release to fire the shutter.

The amount of light reaching the sensor is determined by the size of the aperture – the f number – and the length of time it is open – the shutter speed. These two have to work in conjunction with the ISO number to get a correct exposure. Whilst it is important to understand these three things because you may wish to to be able to adjust them manually later, your camera can use its internal light meter to control some or all of them for you and get a perfect exposure in normal lighting conditions.

Focus
Your camera will have very clever and very fast autofocus facilities and I suggest you start by using them. It helps if you understand a little about how the various autofocus modes work, and they vary from camera to camera, so we’ll deal with those separately. Note that to use autofocus, you may have to select “autofocus” on both the camera and the lens for it to work properly. Again, how to do that varies from model to model. It is helpful to know which part of your subject the camera is choosing to focus on. For example, if you are photographing someone’s face, you will want to make sure their eyes are sharp, so you want the autofocus to focus on the eyes. As cameras vary in how they do this, I can show you on your camera.

Getting your image sharp

Whilst you might in certain circumstances want an image that is soft or blurry, let’s start by aiming to get your images sharp. Two things influence sharpness: focus and blur.

We have looked at focus above – you have to allow the camera to focus properly on the subject. An autofocus setting will do that just before it takes the picture. When you first press the shutter very lightly – not all the way down – it will focus. (We’ll return later to why this is helpful to know.) When you press it completely down, it will take the picture.

Blur is caused by movement. It can be movement of the subject during the exposure (the time that the shutter is open). You would be surprised how much movement can take place – eg of a flower moving in a gentle breeze – during even a short exposure. This will ruin your picture, unless blur is what you want!

Blur is also caused by the camera moving during the exposure – ie by you not holding it steady while you press the shutter. I will show you the generally accepted way to hold the camera to keep it steady. You should breathe in or out gently before you first press the shutter and hold your breath until after you have taken the picture. The effect of blur can be reduced by using a shutter speed that is not too slow – try not to use slower than 1/125 unless you’re using a tripod. You can sometimes help hold it steady by leaning against something like a tree, a wall or a doorway. I’ll show you how. Your camera probably has an anti-blur function that helps – sometimes called “image stabilisation”. Nikon call it Vibration Reduction, or VR.

This kind of blur – caused by you moving the camera, however slightly, during the exposure, is the single most common cause of poor images. To reduce blur, I

  • Use the tripod and remote release whenever I can, or
  • Lean against something firm, or
  • Stand steady and hold my breath while taking the picture

Aperture and Depth of Field

Depth of field is the amount of the picture that is in focus, from the area nearest to the camera to the area furthest away. When you look at a scene, your eye constantly adjusts its focus so that the whole scene looks sharp. The camera cannot do that. It can only focus once. The depth of field depends on the aperture selected. The smaller the aperture (larger f number), the greater the depth of field. Conversely, the larger the aperture (smaller f number), the less the depth of field.

Let’s look at an example. If you were photographing a landscape, you might want a large depth of field, with objects in focus from the foreground near the camera right to the horizon. To achieve that, you need a small aperture, say f16 or f22. If you wanted to take a picture of a flower in a busy garden, you might want to get the flower sharp, but throw the background out of focus to help the flower stand out. Here you would use a large aperture (small f number) to restrict the depth of field.

Conclusion

Being able to adjust all these variables is what gives you control over your image, and is what makes the DSLR the perfect camera for taking more than just snaps.

(c) Colin McLean, August 29 2013

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Neutral Density Filters

The human eye can interpret a much wider range of contrast, ie bright to dark, than can any camera film or digital sensor. The eye is a much more sophisticated instrument than the camera industry has invented so far. This means that on even a reasonably bright day, what you may see as a landscape or building plus a bright sky, your camera will see as a landscape or building (if they’re exposed correctly) and a blank white (overexposed) sky, which is not very interesting or, given what your own eye can see, not even accurate. If you expose correctly for the sky, the landscape or building will be underexposed, ie very dark.

The problem here is the wide range of brightness between the land and the sky, which your camera can’t handle. So what we have to do is reduce the range, and that’s what a graduated neutral density (a Grad ND) filter does.

A Grad ND sits in a holder screwed into the threaded front of the camera lens. Put simply, the top half of the filter is grey (neutral – which does not generate any colour cast) and the bottom half is clear. Its effect is to reduce the exposure on the sky, by letting less light through the grey section, but leaving the bottom part – the land or building – properly exposed. This reduces the range between light and dark and makes it easier for the camera sensor to capture. It also gives you a result that more closely represents what your eye sees or, more accurately, what your eye tells your brain it sees.

A Grad ND filter is rectangular and slides up and down in a holder that screws into the front of the lens. It is wider than the diameter of the lens, and is taller by about 25%. That allows you to slide it up and down to position the border between the grey and clear sections over the horizon – ensuring that you darken the sky, but not the land.

The term graduated refers to the fact that the filter is usually dark (you get various grades) at the top, fading slightly to about the middle of the filter where it gradually changes to clear. The is a soft Grad ND. You also get hard Grad NDs where the top half is a uniform grey and there is a hard edge between that and the clear portion. That hard edge can be more accurately positioned over the horizon in your picture, but it requires the horizon to be flat and level. Hard edge filters are less common than the soft edged ones as the latter are easier to use.

Grad NDs are primarily available for use with SLR cameras, and there are a number of popular makes. The most popular is Cokin. Lee is a higher quality make but more expensive. I use Cokin. I believe that filter companies are now making them to suit smaller compact cameras.

There is a second type of Neutral Density filter which is used for different purpose. It is not graduated, but is solid grey over its whole area. As you can guess, it lets through less light over the whole image. That means that for any given ISO rating and aperture, you will need a slower shutter speed. Why?  – you might ask when you usually you want to use a fast shutter speed to minimise the effect of camera shake. Landscape photographers use a slow shutter speed to create that smooth, silky, blurry effect on moving water, such as rivers or waterfalls. In such cases, the photographer may be looking for a shutter speed as slow as 2 1/2 seconds (the effective minimum to blur moving water in average circumstances). This of course means using a tripod and almost certainly a remote cable release (or a wireless one for some cameras). With such a slow shutter speed, camera shake has to be avoided by not touching the camera at all during the exposure. I have taken some exposures using this technique at dusk where the shutter time is 3 1/2 minutes.

It will come as no surprise that the developers of photographic processing software, such as Photoshop, Photoshop Elements or Lightroom, have created a digital equivalent of the Grad ND, which you can apply via your computer. These can be very effective, but to darken the sky to produce some detail, that detail has to exist in the image file in the first place, or there is nothing to “rescue”. If the sky is so over exposed – “the highlights are blown” – it contains no data at all, and no software can rescue that.

Both traditional and digital Grad ND filters have their uses. Most landscape photographers use both.

 

Postscript. When you see a serious photographer checking the image in the camera screen after taking a picture, they are probably not just looking at the image to see if it is ok. The image presented on the screen has been processed by the camera – it is not the original image. For example, the screen has probably been set to respond automatically to the ambient brightness so you can see a clear image, not the original. The photographer is more likely to be checking what is called the Histogram – a graph that shows how much data the image contains at the extremes of darkness and brightness, and tells the photographer if he has the full range of light and dark data that is required for a good photograph. Histograms are a whole other, very useful, subject.

Some examples:

1 – An image with an overexposed sky:

http://www.blipfoto.com/entry/2512079 

2 – An image where a Grad ND (in this case a digital one) has been used to reduce the sky’s exposure:

http://www.blipfoto.com/entry/3160115

3 – An image where a solid ND has been used to give a long exposure to create blurring of moving water

http://www.blipfoto.com/entry/2582112 

4 – An image where an ND has been used to create a very long exposure of 156 seconds, blurring the sea and the moving clouds.

http://www.blipfoto.com/entry/2517991 

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Reflections in a Historic Week

Back in 1999, about a week before the opening of the Scottish Parliament (up the road at the General Assembly, not down at Holyrood), I was planning to take my two daughters along. I rang their primary school as a courtesy to say I was taking them off classes for the day.

“Why?” asked the Depute Headteacher. Recovering my composure, I suggested that if she didn’t know the answer to that question, she should pour a wee dram when she got home that night, and sit down to have a wee think to herself.

The three of us went, not to any formal part of the day, but just to be part of the event. Now, I expect my girls were more excited by seeing Sean Connery in the parade then Donald Dewar, but when, by accident, we bumped into Big Donald in George IV Bridge later that afternoon, they knew who he was.

Today, twelve years later, they’re not what I’d describe as politically motivated, but I know they remember that historic day.

On the day that Holyrood opened, my (now) wife and I went into Edinburgh for the event. Again, nothing formal; just to be part of it. And a part of it we indeed were. For, oblivious to the formal shenanigans going on inside the Parliament, there was music outside, and perhaps inevitably, a ceilidh ensued. And we were the first to take the floor, to a few good cheers. It was a great moment; for us, the best single moment of that historic day.

Wednesday of this week was another historic day. One that feels like the start of a new chapter in the nation’s life, as did the two days I mentioned above.

The first few years of the Parliament were not without their frustrations, and I recall remarking to friends that it was like when your children were at primary school. Exciting, interesting, and absolutely necessary, but oh it would be nice when they grew up and reached the secondary.

It feels this week as if the Parliament and the country has definitely reached the Big School. A different set of friends to play with, and no doubt there will be one or two bullies in the playground too. But standing up for yourself is something we all have to learn to do. Scotland has without doubt voted to stand up for itself and decide some things for its new future. Is that the bell I hear ringing? Time for classes to begin.

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Blog for my daughters

It can’t have escaped your notice that in many parts of the world in recent months, there has been trouble.

Trouble because people have been rising up against rulers and governments that have been keeping them locked into poverty and oppression. Keeping them from having a say in their own countries’ futures.

Having a say in your own future; in how you want to shape the future of the country you were born in, grew up in and live in, is called democracy. It is a very important and precious thing and the single most important thing about it is the freedom to vote; to choose freely who you want to guide Scotland’s future.

It is as rare and precious as any jewel. People have fought and died for the right to vote, and people are still fighting and dying for it. It is a privilege that not everyone has, but you do.

So however busy you are today. However uncertain you are about the flood of arguments and leaflets about whether this party is better than that party, whether this candidate is better than that. However uncertain you are about any of that, go out today and vote. If you want to be proud of the country you live, work and play in, make it proud if you, by going out and voting. To do so is a rare and precious thing.

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Twitter and Blogs – a complete beginner’s guide

For me, certainly, a feature of this Holyrood election has been the impact of the volume of writing, opinion and information accessible via the internet and social media such as Twitter. I meet lots of friends yet to enter what can seem a world of mystery – “I don’t get Twitter” – so I offer this complete beginner’s guide, by a not quite complete beginner, with invaluable assistance from Aileen Lamb @AileenLamb , Kate Higgins @Burdzeyeview and Nerys Watts @NerysWatts. Definitely not beginners!

First step into all this for me was getting an iPhone, almost exactly a year ago. Though I was already accessing the internet regularly for all the usual purposes, it was the iPhone that transformed all of that into something that was now part of – and admittedly sometimes intrusively so – daily life. I could instantly send photographs from holiday to my children and friends. I could use Googlemaps to find something in a strange city. I could check out new tunes on iTunes or YouTube. And I could read the news when and where I wanted, and range across a selection of media rather than a single favourite newspaper. However, you can blog and tweet from any pc with an internet connection. 

Next was the discovery of Twitter. A colleague – a politico, I’m sure she’d admit – set me up on Twitter and I was off. The basics were dead easy to grasp (though there is some stuff about direct messages that I’m still not quite certain of). Through Twitter, I was exposed to links to blogs on WordPress and its many siblings.

I now use Twitter as my primary source of news and information. For the uninitiated, who may know that a Tweet is restricted to 140 characters, the key is discovering that some of these character spaces can be in the form of a link to another place. That other place might be an online picture (or one just attached from your own device, eg iPhone), to a sound or film clip, to an article in the online version of a newspaper, journal or magazine (and I have discovered here journals that I did not know existed – it is like being let loose in a giant newsagents), or to a blog (a blend of the words web and log – see http://en.wikipedia.org/wiki/Blog ). 

In my view, the really great thing about Twitter is that you tailor it to exactly your preferences. You only receive tweets from people that you elect to follow, and none of the junk that, for example, appears in your yahoo inbox. Of course, the people you do elect to follow can retweet some else’s tweet/s, and you’ll receive them too. But it’s all instantly changeable to suit your preferences. If some one you follow tweets stuff you decide you don’t want to see, or clutters up your account with too many retweets (a retweet is when you forward some else’s tweet), it is the work of seconds to unfollow them. 

If you were concerned about volume of incoming material, that too is in your control. I try to keep the number of people I follow to about 100, but I observe there are some who follow thousands of people. You might wonder how they find time to live real lives. But they might be using Twitter Lists to organise their followers. Twitter Lists pull together all the people you follow under headings you choose – so you don’t have to read everyone’s tweets when perhaps you only want to read those from the 10 people on your ‘political commentators’ list.

If you haven’t seen a tweet, here’s an example: 

BBC Politics (@BBCPolitics)
02/05/2011 12:52
Last week for election campaign bbc.in/kpJhpX

I received this because I follow a tweeter/source called BBCPOlitics (the @ prefix is a Twitter thing, denoting someone who tweets). Note the text of the tweet itself is very short “Last week for election campaign”. The real significance is in the link  at the end (properly called a hypertext link). You’ll be familiar with the format if you use the internet. If you don’t use the internet, you probably don’t want to be reading this and should continue to enjoy life on your own planet. When you click on the link, it takes you to a BBC article about the election campaign. 

You’ll have noticed that the links to some web sites are very long. And as a single tweet can only contain a maximum of 140 chracters, you don’t want your tweet filled up with the gobbledegook that is a web link. Panic not; there is a solution. Go to one of the websites such as www.tinyurl.com or http://bit.ly/ . These clever sites shorten your long weblinks to very short codes that take up much less space but work perfectly. How do they do that? By magic. 

Not surprisingly, there is loads of help available for free on the Twitter web site: http://bit.ly/9VvRSD (this was a long link and I shortened it using Bitly)

One of the many other features of Twitter is that is is completely anarchic – you can tweet whatever you want, subject to the usual rules of decency and libel. It’s self-policing. If you see a tweet you think is inappropriate (as opposed to one whose content you disagree with, and there’ll be plenty of these as it’s a great forum for debate), you can request that it be removed. Similarly if you are followed by someone whose behaviour on Twitter is inappropriate (and I’ve had one or two in my short time), you can ask that they be removed too.

If you see a tweet by someone you think might be interesting, you can follow it to their home page and see who they follow and who follows them. Through this you can build up your own list of who to follow, reflecting your interests. 

Twitter is very “instant”. There is a fascinating series of tweets, for example, by a guy in Pakistan who heard helicopters overhead one night in early May. He had no idea what was going on, and even joked about getting his giant flyswat. His gradual realisation of what he was witnessing, and the flood of tweets and media coverage that followed, is fascinating to read.

Many tweets carry links to blogs. A blog is a piece of writing (it may include photographs, and indeed other links) that is hosted (stored) and accessible online. 

Many blogs, including this one, are hosted by services such as WordPress http://wordpress.com/  and are free to the users – both writers and readers – and easy to set up. Other blogs are hosted on a web site created by/foran individual. There are plenty of web site developers that allow you to create and host your web site using a template for free, the price being some advertising of their enhanced and paid-for services. I use Moonfruit http://www.moonfruit.com/ for a web site for our local folk club. 

Here’s an example of a tweet with a link to a blog: 

Gerry Hassan (@GerryHassan)
01/05/2011 23:46
My take on the BBC leader and prev leader debates. Is this the best we can really do? www.gerryhassan.com/

Like the tweet above from the BBC, I received this one because I have elected to follow Gerry Hassan. Though the text here is slightly longer, the real feature is the link to a blog by Gerry Hassan, in this case hosted on his own web site   www.gerryhassan.com/ . Hassan will write these blogs and put them up on his web site himself, free of any editorial control by a third party (though he will have agreed with the service hosting his web site that he will follow normal rules of decency and libel). 

You too can blog till your heart’s content, but there is a principle that’s worth remembering. Musician and one-time parliamentary candidate Donnie Munro once told me that you should not write a song unless you have something to say. Definitely a point to be taken on board by prospective bloggers everywhere. 

Give Twitter a try, but be warned, it’s addictive. For me it has replaced all the news apps I installed on my iPhone and which I hardly ever use now. It, and the links to various blogs, have exposed me to all sorts of thinking and writing that I would never have seen before; all of them interesting and some of them excellent. Enjoy them.

Again, many thanks to experienced tweeters and bloggers Aileen Lamb – @AileenLamb , Nerys Watts – @NerysWatts and Kate Higgins – @burdzeyeview (Kate blogs at http://burdzeyeview.wordpress.com/ )  for their invaluable contributions and advice. Ta!

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There is green in the forest again

Though it would be rash to think that winter had passed, and there was still quite thick ice on the pools at the side of the Kirkburn path, today was the first day this year that I was really struck by how vivid some of the greens were. Granted, it was the ferns and mosses, but the depth and strength of the colours was eye-catching among the browns of everything else.

I didn’t have much time to spare, so I only walked for about an hour and a half, and there were a good few other people around. Including some poor guy who had lost his dog three hours earlier – I could still hear him, and other members of his family who had joined him, shouting for the missing Beagle an hour later. I hope they found it. When my daughters were younger, we always had a dog, and lost them plenty of times. But they always turned up eventually, even if it was impossible to predict how long it would take.

The ground was wet but firm underfoot and I made good progress. Noticeably quicker than in the deep snow of recent walks, though I still find them the most enjoyable of all. However, it will be a pleasure to watch the forest turn green again in the months that lie ahead.

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Possibly the worst service I’ve ever experienced

We’d been in Edinburgh all day and found ourselves in Portobello High Street. Needing something to eat, the Blue Bean Coffee House looked just right. Quite busy – a good sign – and the decor and ambience looked good. The menu looked good too.

There were two teenage boys serving front of house, and a girl possibly early 20’s in the kitchen. A tiny suspicion arose when one of the boys, instead of coming over to our table, asked from the behind the counter, over the heads of other customers, if we were ready to order. We both ordered soup with crusty bread and cheese, plus two slices of carrot cake and coffees to follow.

We waited far too long for our soup. What were they doing to it other than warming it up? At 4.00pm I doubt they were making a fresh batch. However, when it finally arrived, it was good, it was hot and the portions were generous. The bread was fresh, though no sign of the cheese.

The soup bowls were cleared and we waited for our two slices of carrot cake and coffees. And waited. And waited. And waited. The three staff were all out of sight in the kitchen. One of the boys came out twice. On the first occasion he checked his mobile phone which was lying on the counter. But not one single glance in the direction of his customers before disappearing back into the kitchen. Second time he came out, he seemed to play with his phone – maybe sending a text. He looked out the window but again not a single glance towards his customers. I watched him carefully both times, hoping to catch his eye.

Eventually, my wife popped her head round the kitchen door and asked if we could have our coffees. All three staff were sitting on a worktop, chatting. The two coffees arrived but only one slice of carrot cake. As soon as we saw it we both simultaneously decided against asking for the missing second slice. The cake was dry and the icing had fallen off as it too was dry. The boy actually asked if we’d like an extra fork in case we were sharing.

The coffees were both good.

I went to ask for the bill. No bill was offered but I was asked for the total amount. We both wondered whether the bill had been based on the two pieces of cake ordered or the one served. I queried it with the second boy who checked it and refunded me the price of a slice of cake. Not a single word or look of acknowledgement or apology from either of them.

I asked the boy who had served us whether he watched the current TV series with Michel Roux called “Service”. He looked blank and said nothing. I suggested he should watch it as he might learn something. No reaction whatsoever.

I am not pointing a finger at either innocent teenage boy. They just didn’t have a clue how to do their jobs. And that’s because they’d had no proper training. It’s the owner, who claims on her web site to have had “over 35 years of catering experience”, who needs to watch Michel Roux.

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