The Raj Chronicle

Before we get into the details of the individual aspects of a good photograph as discussed in the last post the following are the three most important aspects that every photographer must know.

1. Film Sensitivity

2. Shutter Speed

3. Aperture

While a modern DSLR camera seems to present a mind boggling number of settings, these three are the most important and in fact the only primary aspects that matter. Not surprisingly these three aspects have applied to all cameras including film (SLR or otherwise) and EVF digital cameras. In fact, these three concepts apply all the way back to the very beginning of photography itself.

The primary elements of a camera

Before we can understand these three factors, we need to understand how a camera works: not the microprocessor powered complex modern marvel that is DSLR but the fundamental aspects that are common to all cameras including cheap disposable film cameras. A camera is made up of a lens element in the front through which light enters the camera and a sensor that records the incoming light. In film cameras the sensor is a film and in digital cameras it is either a CCD or CMOS sensor. Photographic film is coated with light sensitive chemical compounds that when exposed to light undergo chemical reaction resulting in new compounds. The amount of new compounds formed is dependent on the amount of light that hits a specific part of the film. A digital sensor converts light into electric energy which is then quantized ( a technical term for measuring the electricity and converting it into a discrete number such as 127) and stored in digital storage such as compact flash or SD cards. There is always a third element in between the lens and the sensor which is the shutter. The shutter always remains closed when the camera is not operational. It opens for a short amount of time to let light in and then closes. The sensor only records the light that falls during the time the shutter remains open.

So far so good. In fact most of you already know this. You might be thinking why am I going to such a great extent to rehash what you probably learned in middle school. Bear with me my friends because while the above explanation may be obvious the conclusions are deviously subtle.

Film sensitivity

Let’s start with the sensor. Do all films produce the same amount of chemical compounds when exposed to the same amount of light? Of course not. Believe it or not, you can still buy 35 mm film and if you do you will notice an ISO rating on the film that usually ranges from ISO 100 to ISO 800. The ISO stands for International Organization for Standardizations. Without getting into complicated details here is what you need to know. A film that is rated ISO 200 will have twice the sensitivity of ISO 100. In that same vein a film that is rated ISO 800 will have eight times the sensitivity of ISO 100 film. So why bother with lower sensitivity film at all in the first place? Why not get rid of it and stick to ISO 800 for everything? Speaking of which, why stop at ISO 800? Are there films with higher sensitivity? Why not use them?

As you will discover with everything in photography, there are tradeoffs and compromises. The additional sensitivity comes at a price, namely graininess. Generally films with higher sensitivity will result in images with higher image grain or noise. And yes, there are films with higher sensitivity all the way up to ISO 3200 as far as I know. So what does film sensitivity have to do with DSLR photography? After all, you cannot switch out the digital sensor in your DSLR and replace it with a sensor of higher or lower sensitivity. While you cannot replace the digital sensor, the built-in sensor does exhibit the same type of higher sensitivity for higher noise tradeoff. Have you tried turning up the volume really high on a cheap boom-box? If you did, you would have noticed that you can get the boom-box to play really loud but with significant distortion and noise. Similarly you can think of a volume knob attached to the sensor that the DSLR camera can tweak.

Shutter speed

Next lets take a look at the shutter. The automated electronic shutter is a marvel considering how quickly it can open and close. At the same time it is also very easy to understand because that is all it does: open and close. The most interesting aspect about the shutter is how long the shutter stays open. The amount of light falling on the sensor increases as the amount of time the shutter remains open. Shutter speed is usually measured in seconds. So a 2 second shutter speed means the shutter remains open for 2 seconds. A 2 second shutter speed is actually quite long. Even a 1 second shutter speed is very long. Most portraits are taken with a shutter speed that is a fraction of a second such as 1/200th of a second. As elementary school has taught us, 1/200th of a second is twice as fast as 1/100th of a second. Straightforward right but here is where the photographers start messing with the rest of us. Due to space constraints or due to deliberate planning (I am pretty sure it is the latter ) DSLR cameras will usually show only the denominator of the shutter speed for fractional shutter speeds. So lets say your DSLR camera currently shows shutter speed as 200. It means that the shutter speed is 1/200th of a second. If you decrease the shutter speed, that is increase the amount of amount time the shutter stays open, the shutter speed display will change from say 200 to 100, 50, 20, 10, 1, 2, 4 and so on. Wait, what? Did the numbers just count backward to zero and then bounce back from zero? Here is how you should read it. 1/200, 1/100, 1/20, 1/10, 1, 2 and 4. See what I mean about photographers messing with the rest of us? Go back and read the last paragraph again until you are completely used to the way shutter speed is displayed. There is really nothing complex about shutter speed except for the way the camera displays it.

The relationship between shutter speed and film sensitivity

Now that we understand shutter speed and sensitivity lets see how those two relate. Whenever you increase sensitivity you will have to increase shutter speed (increasing shutter speed decreases the amount of time it stays open) to compensate if everything else remains constant. Why? Because increasing the sensitivity makes the sensor more sensitive to same amount of light. By increasing the shutter speed, we can decrease the amount of light that falls on the sensor and thus compensate for the increased sensitivity. Assume you took a photo at ISO 100 with a shutter speed of 1/200th of a second and it came out fine. Everything else remains the same and you change the ISO from 100 to 200. You will have to increase the shutter speed to 1/400th of a second to compensate and get a similar picture. You could also change the lens aperture to compensate which leads me right to the next topic: Lens aperture.

Aperture

When it comes to explaining lens aperture, a picture is worth a thousand words. Every SLR lens has a metal blade mechanism called the aperture that can electronically open and close. In the picture to the right, the lens pictured in section 1 has its aperture relatively open at f/2.8 while the same lens pictured in section 2 has it stopped down to f/16. Why do we need an aperture mechanism in a lens? The aperture mechanism lets us control the amount of incoming light into the camera and also the depth of field. You can take one look at the picture above and understand why a wide open aperture would let it more light than an aperture that is mostly closed but what is this depth of field?

Consider this picture to the left. Only one of the flowers is in sharp focus while the rest of the flowers lie just out of focus. The grass in the background is blurred to the point that you cannot tell whether it is grass. This is an example of a picture with shallow depth of field.

Now consider the picture to the left. Notice how all of the flowers in the image look sharp and in focus. While the grass in the background does look out of focus it still quite visible and discrete enough to make out that it is grass. This is an example of a picture with a relatively deep depth of field.

So when you open the aperture blades you let a lot of light in but you end up with a shallow field of depth. On the other hand you can close the aperture blades to create a small light inlet with a deep field of depth where everything is in focus but end up letting very little light in. It should be noted that a shallow depth of field is not a bad thing. It can be used creatively to bring depth information to the picture and keep the interest on the subject. A deep field of depth is useful in landscape pictures. So there is no right or wrong depth of field. It all depends on how you want the picture to look.

Unlike sensitivity and shutter speed which are inherently present and controlled internally by the camera, the aperture mechanism is part of the lens. Aperture is measured and specified using f-stop numbers which is a ratio between the focal length of a camera and the diameter of the aperture opening. Each lens is capable of a specific minimum (narrowest) and maximum (widest) aperture indicated by the lens manufacturer. It is not hard to close down the aperture so the minimum rating is usually not that interesting. Besides closing the aperture beyond a certain level causes diffraction phenomenon in the resulting picture. The more interesting specification is the maximum aperture. This is the widest aperture setting a lens will allow. Widest aperture usually ranges between f/1.2 to f/4.0. Here again there are curious non-intuitive properties regarding how aperture is measured and displayed. Higher f-stop numbers indicate smaller aperture openings. So f/4.0 is a smaller aperture compared to f/2.0 which in turn is smaller compared to f/1.2. Two aperture settings are said to be separated by one f-stop if the larger setting allows twice as much light as the smaller one. Here is where it gets curious. If your lens is currently set at f/4.0 aperture and you want to allow to twice as much light what aperture setting should you set it to? One would assume you would have to set it f/2.0 but that would allow four times the light. The next f-stop from f/4.0 is actually f/2.8! Here is a series of standard full f-stops:

1.0 1.4 2 2.8 4 5.6 8 11 16 22 32 45 64 90 128

Usually DSLR cameras allow one-third f-stops as follows:

1.0 1.1 1.2 1.4 1.6 1.8 2 2.2 2.5 2.8 3.2 3.5 4 4.5 5.0 5.6 6.3 7.1 8 9 10 11 13 14 16 18 20 22

The relationship between film sensitivity, shutter speed and aperture

Now that we have understood all three factors lets see how they all relate together. On one hand you have the sensor whose sensitivity you can adjust based on the incoming light. On the other hand you have two ways to control the amount of light that falls on the sensor: the aperture opening and shutter speed. Whenever you adjust one of them you will have to adjust one of the other two to compensate. For ex: If you decrease the aperture setting to increase depth of field you will have to decrease shutter speed to compensate the reduced amount of light entering the camera by exposing the sensor for longer duration. Another option is to increase the sensitivity of the sensor. It does not matter which one you tweak, you will have to compensate using one of the other two settings.

All of this sounds complicated. How the hell are you supposed to calculate exactly what to set these three values to? There is indeed a mode in every DSLR that does allow you to set these values independently: the full manual mode. It is definitely not for beginners. Even most experts do not use the full manual mode unless they are doing something so subversive it can only be called creative. Instead most of the time you will choose one of the automatic modes or a semi-manual mode. Let’s look at the two most common semi-manual modes first.

Aperture priority or Av mode

In aperture priority mode the photographer chooses to control the aperture and sensitivity only. The camera calculates the appropriate shutter speed by measuring the incoming light. This is the mode I most commonly use so I can control depth of field.

Shutter priority or Tv mode

In shutter priority mode the photographer chooses to control the shutter speed and sensitivity only. The camera calculates the appropriate aperture by measuring the incoming light. This mode is most appropriate when you want to shoot fast action or intentionally slow down certain scenes such as flowing water.

Although you might not be aware, when you select one of the automatic modes you are specifying a priority to the camera. For ex: Choosing portrait mode forces the camera to keep the aperture as wide as possible with the ISO set to some arbitrary safe value such as ISO 400 in Canon DSLR cameras. We are now at a point to discuss more details about exposure which I will follow up in a separate post. Until then, Ciao.

First of all, I apologize for the lack of updates to this blog in the last few months. To avoid comment spam, I turned of comments altogether and then started to wonder if anyone actually reads my blog. Lately quite a few of you have pinged me directly making me realize that this blog does have followers. My bad. I promise to make more frequent posts in the future.

So lets get back to photography. One of the common questions I get about photography is what settings I use and if I really use all the bells and whistles in my camera. That tells me that most of you are unfortunately approaching DSLR photography from the wrong angle (pardon the pun). All the bells and whistles in the camera will do you no good unless you know what you want the camera to do. What do you want the camera to do? In order to do answer that we have to understand what makes a good photograph. It is a deceptively simple question because pretty much everyone can tell a good photograph from a bad one but cannot particularly break it down into distinct factors. Here is my attempt to break it down in no particular order:

• Exposure
• Focus
• Composition
• Perspective
• Color
• Depth of Field
• Sharpness
• Contrast
• Lighting

Understanding how to get these individual factors right will naturally lead us to asking the camera to do specific things such as increasing exposure, decreasing depth of field etc., We can then map these specific requests to settings and adjustments to the camera. In the next few posts I will start addressing each of these factors. The comments section are open again. So please let me know you feedback and what you would like me to address.

As you probably know, one of the primary advantages of getting a DSLR camera is the capability to choose and change lenses at will. While choice is great, an overwhelming dose of it can leave you confused. I wish this post was as easy to write and recommend as the the previous one about selecting a camera. Choosing a DSLR lens is a much more involved and nuanced decision. The picture above is only a small collection of the lenses offered by Canon. Before I explain the details about how to choose a lens, let me make a few quick recommendations for the impatient audience.

Unless you are buying the 5D or 1D camera series, your camera will accept both EF and EF-S lenses. EF lenses are standard 35 mm lenses that work with all Canon cameras including film cameras. EF-S lenses were developed specifically for DSLRs with 1.6x FOVCF such as the Rebel series cameras. If you are looking for a versatile, general purpose and affordable lens, go with the Canon 18-55 mm IS EF-S kit lens. The best way to get this lens is with the camera itself as in the Canon T2i kit option.  The latest version of this ever popular kit lens has image stabilization built-in making this a great value. It is true that this is not the best lens to show off the capabilities of your DSLR camera. The build quality of this lens leaves a lot to be desired. As lens apertures go, this is a “slow” lens. Despite these shortcomings I would still recommend this lens for beginners. For a cheap lens it exhibits minimal lens artifacts. You will eventually outgrow this lens but there is plenty to learn even with this underestimated lens.

If you are going to buy only one other lens in addition to your kit lens, I would seriously recommend buying the Canon 50 mm 1.8 EF lens. This inexpensive lens offers serious professional level image quality and large aperture that is very hard to find even in expensive zoom lenses. As we step in to the details of photography, this is a fantastic lens to follow along, experiment and learn. The build quality of this lens leaves a lot to be desired. It has a noisy and slow auto focus mechanism. The manual focus ring is so small that it is almost unusable. There are no focus distance markings on the lens body. So why buy this lens? It is the cheapest, most practical prime lens in the Canon lens family, offers crystal sharp images, sports a large f1.8 aperture and extremely light weight. Did I mention that it is cheap? Don’t over think this one. Just buy it. You can thank me later.

If you are willing to spend a bit more money, have no plans of upgrading to a full-frame camera and want much better image and build quality, I would recommend the Canon EF-S 17-85 mm lens. This lens offers excellent image quality and much better build quality compared with the lenses shown above. This is a great every day walk around lens. I seriously considered buying this lens when I bought my Rebel XT but decided not to because I planned to eventually upgrade to a full frame camera. You cannot use this lens with a full frame camera such as the Canon 5D. The Canon 5D camera was not available or even announced at that time. The only full frame camera available at that time was the professional 1 series camera but I was pretty sure that Canon would eventually announce an affordable full frame camera which it eventually did. You probably do not know if you want to upgrade to a full frame camera yet. I have not given enough information here for you to make that decision. Consequently you might want to hold off on that decision until you read the post about the benefits and downside of using full frame cameras.

Let’s say you are willing to spend more money, want a great lens to go with your starter camera today but also want the option of upgrading to a full frame camera later. If this is the case then you should stay away from EF-S lenses and start looking at EF lenses. When it comes to EF lenses Canon has two family of lenses: The regular lenses intended for the cost conscious customers and the L-series lenses intended for professionals and “prosumers”. In a welcome twist there are a few L-series lenses that cost nearly the same as some high end consumer grade lenses. A very popular L-series lens option for the Rebel, xxD and the new 7D camera is the Canon 17-40 mm f4L lens. Why is this lens popular? Apart from the exceptional image quality of L-series lenses, they are also known for their build quality. Once you have used a L lens, ordinary lenses start feeling toys compared to them. This causes a shopping disorder known as L-itis whereby once you have bought a single L lens you will never settle for anything less. A lens that costs almost the same as your camera might be a rude shock but consider this: I sold my first Rebel XT camera for about 60% of its price. My current Canon 5D is only worth less than half its value today because of the arrival of 5D Mark II but the L-series lenses I invested have only gone up in price. So consider buying good lenses as a lifetime investment. A word of caution: All that build quality and high grade lens components in this lens also makes it relatively heavy compared to the above lenses. The way you handle your camera will need to change to accommodate the additional weight.

Before I close out this post, there is one other lens I would like to recommend: the Canon EF 70-200 mm f4L lens. This is a relatively expensive lens generally speaking but it is also the cheapest L-series lens representing the best value for your money. This is a telephoto zoom lens. You might have heard people say that telephoto zoom lenses are primarily used for shooting birds and distant wild life. Although they make excellent subjects for telephoto zoom lenses that is not the only purpose of such a lens. The 70-200 mm range is an extremely useful and versatile range. I primarily use it for portrait photography. Surprised? Most beginners are because they have these misconstrued ideas about telephoto zoom lenses. In an upcoming post I will explain why this makes an excellent portrait lens and some samples to show you what I mean. Since this is a EF lens, it will work on all Canon cameras. Of all the lenses I have used so far, this is my favorite lens. The sharpness, contrast and color saturation it yields are spectacular.

In my next post I will explain the concepts of lens angle, focal length and aperture. Apart from providing the rationale for the lens selections above, it should also help lay the groundwork for relating these concepts to real world photography.

As frequently asked questions go, this is the most frequent when it comes to DSLR photography: Which DSLR camera should I buy? It seems like an innocuous question but the implication is that a better camera will get you better pictures. After all that seems like common sense, right? Common sense also says that you get what you pay for, right?

My recommendation is to buy the cheapest starter DSLR camera you can find from a top DSLR vendor. I am partial to Canon mostly because I own Canon gear. Canon and Nikon are the top two DSLR vendors for good reason. As of this writing the Canon EOS Rebel T2i is the latest entry level model offered by Canon which I highly recommend.

There are other more expensive cameras offered by Canon but for a beginner it is probably best to stick with the entry level model. So why go with the entry level model when there are other more expensive models?

• The original Canon Rebel, which was a digital SLR revolution when it released, had 6.3 megapixel resolution. The Canon Rebel T2i has 18 megapixel resolution! And this is the entry level camera too. The megapixel race does not matter anymore for most of us.
• There is some subtle difference in image quality between the entry level and the more expensive models but you will be very hard pressed to notice it.
• The camera is only the first equipment you will need to invest in for good DSLR photography. You will also need to invest in good lenses, a flash, memory cards (SD & Compact Flash), tripods, polarizers and filters and that is just for regular non-studio photography. The money you save by buying an entry level model is much better spent on DSLR accessories.
• As I mentioned in the previous post, the most important factor in taking good pictures is the photographer, not the camera. More expensive cameras sport additional features but for a beginner they are simply esoteric and only tend to confuse you more.

So what exactly do you get if you decide to spend more money and get a higher end camera? Let’s use Canon as an example again. The next step up from Rebel T2i is the Canon 7D. The resolution and image quality that you get from the 7D is exactly the same as the Rebel T2i. The Rebel series has a polycarbonate shell where the 7D offers a more rugged magnesium alloy body. The 7D also offers more focusing points and a higher frame rate for shooting continuos still photos. Will it matter to you as a beginner? Hardly. The size, weight and build quality are the most noticeable differences you will find. The 7D sells for roughly twice the price of Canon T2i. The 5D mark II is the next step up from the 7D and it does offer more resolution but that is not why it is so much more expensive. Where the Rebel T2i and 7D sport APS-C sized CMOS sensors with a 1.6X field of view crop factor, the 5D sports a full frame 35 mm sensor with no crop factor. There are several advantages and disadvantages in working with a full frame camera. I will explain the differences in an upcoming article. Suffice it to say that if you are a beginner you will not even appreciate the difference. While there is a slight difference in image quality and resolution, you will hardly notice it on a computer screen or regular sized prints.

At the risk of sounding like a broken record let me restate that spending more money on your DSLR will not get you better pictures. We definitely live in very interesting times where even the entry DSLR has such amazing image quality and features. In the next post I will tackle the next most common DSLR question: Which lens should I buy?

A few years ago a friend of mine bought a Canon DSLR. He noticed that I had the same model and remarked that he had never really used any other mode other than the auto mode. There was another friend who remarked that his DSLR in auto mode was so good that he could not really envision taking better pictures by out thinking his camera. The DSLR market has been hugely successful in the last few years bringing quality photography within the reach of masses. Only a small fraction of those buyers ever really use their camera to its full extent. Have you heard the adage, Guns don’t kill, people do? I think that it is also apt for cameras. Cameras don’t take pictures, photographers do. You could have the most expensive DSLR but if you do not learn a few simple things about photography you could be producing mediocre photos at best.

My own DSLR journey started in early 2005. I was outgrowing my Sony F-707 that I bought in late 2001. Sporting a 5 MP sensor, a Carl-Zeiss lens and video recording capabilities, the F-707 was the best digital camera when it came out. I was blissfully ignorant of both the film and digital SLR cameras and their features for quite sometime until I started seriously trying to take better pictures. I soon realized that no EVF camera could match the optical capabilities of a digital SLR. Fortunately the Canon Rebel XT was released with a kit lens for just under $1000 around that time. By today’s standards that is on the pricey side but breaking the $1000 barrier was an important psychological achievement. I have been hooked on digital SLR cameras ever since. I currently own a Canon 5D Mark I, a 17-40 mm EF f4L lens, a 24-105 mm EF f4L lens, a 70-200 mm EF f4L lens and a real cheap 50 mm EF 1.8 prime lens. I also own a bunch of filters, flashes, mono lights, umbrellas and soft boxes.

I have always been a self learner so I did not take any photography classes. Rather I learned by experimentation and research. One of the best things about a digital camera is that you can take many bad pictures that do not cost you any money and you also get instant feedback. You can simply delete the practice pictures and try again. So I learned mostly by trial and error. I know enough to know that there is still a lot to learn.

Several friends have asked me to share some photography tips. Why would you want to learn from an advanced amateur like me instead of a pro? I am guessing that the pros tend to assume that you want to be a pro too. They tend to use a deluge of technical terms and details. I hope to make this much easier by only focusing on what you need to learn using a step-by-step approach that is easy to follow. In this blog I will try to share with you the most important tips about DSLR photography that I have learnt over the years. I would love your feedback and will try to answer as many questions as possible. Thanks for visiting the photography section of my blog.