One of the most daunting experiences for an SLR owner can be deciding which lenses to choose to achieve their photographic goals. The sheer number of possibilities can seem overwhelming when trying to narrow things down to a manageable kit, both expense- and weight-wise. Further complicating matters is that what works well for someone else may be entirely different than what will be best for you. Choosing lenses goes beyond mere quantitative measurements. Your aesthetic sense of how you see the world around you, along with the genres of photography you pursue, and the conditions you will be working in all have a direct bearing on which lenses will be most suitable for you.
Too many of us have learned the hard way about which lenses are best suited to our needs and abilities. Trial and error does often eventually lead us to the right conclusions, but with a considerable amount of wasted time, energy, and MONEY. Could there be a better way?
To start with, there is no way to completely eliminate trial and error from the process. It takes time to fully evaluate why a certain focal length or type of lens will work or not for you. You will also find that your needs and (hopefully) abilities change over time. So the objective of this article is not some sort of magic formula that will guarantee you the perfect lens set for the rest of your life. Rather, its admittedly more modest aim is to help you to avoid some of the common pitfalls of the lens selecting process. Now, while we will be looking at this from the perspective (sorry, I couldn't resist) of manual focus lenses for 35mm film SLRs, the general principles can be applied to interchangeable lenses of all sorts, regardless of format size whether analog or digital.
Traps to Avoid
#1) "So-in-so" says this is the best lens ever! It has insane sharpness from corner to corner wide-open, zero distortion, bokeh balls that melt in your mouth, focus helicals made from premium-grade unobtainium greased with oil from unborn sperm whales...yadda...yadda...yadda...
Even if this was all true, remember that "so-in-so" is only one person with their own subjective viewpoint, and their own unique circumstances. This is not to say that you should not pay attention to the reviews of others; they can be very helpful, but only when you appraise them in light of your own needs. It's also wise to analyze how said reviewer arrived at their conclusions. Did they elaborate on what type of standards they were using to evaluate the lens and the conditions that they were using it in? Buying (or not buying) a lens on the sole basis of one person's opinion is a risky proposition. Being aware that most reviews are of a single copy of a particular lens is very important, too. There is this annoying thing called "sample variation" that basically means that there will almost always be be lousy copies of a given lens and outstanding copies due to manufacturing anomalies. Another crucial factor, dealing as we are almost entirely with used lenses in this context, is how hard of a life the lens has lived (e.g. dropping or smacking lenses into solid objects rarely improves performance). It is the smart thing, therefore, to look at several reviews, if possible, to determine the overall reputation of a particular optic. Keep in mind, too, that there is no guarantee that your particular copy of a lens will be lousy, average, or outstanding. This is one of the trial and error things that cannot be avoided, especially with used lenses. Be warned, it may take a few tries to get a good copy.
#2) Buying a lens based only on its specifications. This doesn't mean ignoring specifications completely, but restricting yourself to only constant aperture f/2.8 zooms or f/1.4 and faster primes, or some other quantitative measurement, merely for the sake of the numbers, is very likely going to be a waste of resources. Packing a bag full of such high-speed lenses is definitely going to take more energy. Which may be fine with you, if they satisfy a real need, not just a numeric one :-).
It seems like, these days, we want everything reduced to numbers that denote the desirability of manufactured goods, from dishwashers to diapers. To a certain extent, specifications can reveal valuable information about a lens, how it relates to other lenses, and features that may be useful to you. The danger lies in putting all of your eggs into the specs basket. Because so much of our interaction with lenses is based on what they show to our eye (something that is not yet quantifiable, and probably will not be so for quite some time), the eye-test should take precedence over numbers on paper (or a screen). There is also the matter of determining which specifications should have greater priority for your personal situation.
#3) Favoring quantity over quality. You will be far better off financially, creatively, and your back and knees will be much happier if you have a few quality lenses that actually fit your needs and style rather than a bunch of middling lenses that cover every focal length. There are so many choices when it comes to focal lengths for both primes and zooms that it is very easy to get caught up in trying to have the "perfect" lens for every situation and covering every focal length. The reality is, for most of us, that this is: a) not economically viable, b) not physically viable to carry around for any length of time, and c) a surefire way to get bogged down in thinking about equipment rather than actually taking and making images.
Another application of this principle is to only take what you need on a particular shoot rather than your whole arsenal regardless of how good your lenses are. There are plenty of articles online that can help you to develop a strategy for carrying only two or three lenses (or even a single lens) for different situations. This achieves a few aims: 1) it makes you really stop and think about your photographic needs and goals, 2) by restricting your options it forces you to make the most of what you have which often leads to greater creativity, and 3) it reduces the distraction of packing a bunch of heavy gear by allowing you to focus more on photography rather than your body's complaints.
Strategies to Employ
1) Look at good photographs and analyze what you like about them and what you would like to incorporate in your own work. This does not mean copying others' work. That is a dead-end street; you will be stunting your own creative growth. But, you will most likely find that there are certain perspectives, genres, and looks that appeal to you more than others. Learning what you like and how to achieve it is the first step to making good choices when it comes to lenses. Let's consider three areas in more depth.
#2) Determine your budget and which features are must-haves versus nice-to-haves or not needed. Do you really need that hulking 35/1.4 prime lens if you are a backpacker primarily shooting landscapes in daylight? Or will an f/2.8 version that weighs 40% less, takes up 35% less space, and costs 75% less than the 1.4 do the job? Or maybe the f/2 which slots neatly in between for half the cost of the 1.4? Or if you really need f/1.4, could you get by with the 50/1.4, which can be had for the same cost as the 35/2.8 and weighs only a few grams more? Lest we get caught up in the percentages (those are specs after all, aren't they ;-), will any of these lenses give you the "look" you want to achieve? Maybe you will need something wider, like a 24mm or 20mm. Interestingly, one of the most acclaimed landscape photographers of the late 20th century, Galen Rowell, often took only a 20/4 prime and a compact 80 - 200mm zoom with him on his forays into the backcountry. Look at his work and see if you think his two-lens kit held him back, or perhaps if it enabled him to get to places (and PERSPECTIVES ;-)) he otherwise mightn't have if he was packing 4 or 5 lenses and a couple of backup bodies. That is not to say that GR didn't have or use other equipment, but he was a master of taking only what was truly needed for the assignment at hand, instead of being mastered by his equipment.
On the subject of budget, once you have determined which focal length most closely matches the way you see the world, don't be afraid to slide a higher percentage of the budget to that lens. It will probably be on your camera the majority of the time, so it may be worth it. Also, if you have a good copy of a lens, please, PUH-LEEZE don't fall for the grass-is-greener impulse to try and find one that's just that little bit better. Just go take some pictures and enjoy yourself. Don't ask me why, just take my word for it ;-).
#3) Think long and hard about how much weight and bulk you can really handle. You may have noticed this current running already in this post and several others. When I was in my early 20's (and a bit of a slave to having the exact lens for the exact purpose thing) I thought nothing of cramming 5 or 6 lenses and an extra body in my pack. Leaving aside for the moment the inevitable misses of moments due to being caught out changing lenses when I should have just been getting the shot, I now cringe at the thought of that much weight. My knees and shoulders do not cringe...they now scream loudly and often when I am packing a single body and one or two lenses (and a bottle of painkillers) in my daypack :-0. Experience can be a cruel mistress. Obviously, if you are in a studio or another environment where you are not required to pack all of your gear with you, your priorities will be different because weight and bulk are not such a big deal. The point is to analyze your needs carefully and prioritize accordingly.
In Part 2, we will examine in more detail the different focal lengths of lenses, and begin to explore how they relate to each other.
How to Choose Lenses (4-part series) - Popular Photography Shoptalk column - April, May, June, July 1984 by Norman Goldberg.
Choosing a Simple Prime Kit - Thom Hogan @ dslrbodies.com
Suffers from an 18-year and counting film and manual focus SLR addiction. Has recently expanded into 1980's AF point and shoots. He even mixes in some digital. Definitely a sick man.