How to Find the Right Lenses

How to Choose a Camera Lens or Lenses for Long and Complex Projects

A professional deals with greater complexity on projects, and must get it right every time. Here’s my methodology on how to choose a camera lens for long form projects.


This article explains a few strategies you can use to choose a camera lens or lenses for long and complex projects that don’t have huge budgets. By long and complex, I mean the following:

  • Feature films that cover many locations and scenarios,
  • Documentaries that take you to remote locations,
  • Editorial journalism (For ENG you would ideally use a broadcast camera with a zoom lens),
  • Wedding business,
  • Corporate video business, etc.

Collectively, I called these ‘long form projects’ (it’s a word I cooked up). The challenges of long form projects are:

  • Many different lighting conditions, often unpredictable.
  • Locations with spaces that are not always under control.
  • You are stuck with your gear and can’t change it midstream.
  • You have a limited budget so you can’t buy or rent everything. Even if you had a lot of gear, you might not be able to afford assistants or transportation to lug it around!

These are problems professionals face and must overcome on a daily basis. Don’t misunderstand, this article isn’t about choosing lenses for your camera. If you’re beginning and looking to add stuff to your kit, start by reading What lens to get? If you are stuck about focal lengths, this might help you: How I understand focal lengths.

This article moves beyond the kit, and looks at lenses as weapons you pick for each fight. If your career is important to you, you know your choices will dictate your future – big time.

Here’s my methodology. Feel free to modify it to your taste.

Step One: Aperture

Let’s start hard. I don’t consider any lens with a maximum f-number greater than 2.8 (f/2.8) a professional lens for video.

I’m sure there are many who disagree with me. Of course you can use your 18-55mm kit lens, or the lens on your iphone, or a hole in the wall. But I’m not talking about image quality, but something more. Look at the first image in this article. The first shows a Canon 135mm f/2 L lens – one of the sharpest on planet earth. The second is a cine-modified version by GL Optics that costs $3,500 to perform (excluding the lens).

Why on earth would anyone pay for such a modification, if ‘forum-trolling fanboy’ image quality was the only criteria? Experience teaches you things are more complex than they seem in the beginning. Luckily, experience also gives you the skills and wisdom to deal with increasing complexity. Okay, mini-rant over, let’s get back to topic.

Obviously, location light plays a major role in your choice of aperture, but you don’t want it to. E.g., there might a shot where you’re absolutely certain you’ll have enough light to shoot at f/5.6, say, but due to unforeseen factors you are forced to wait till dusk to shoot the same scene. If you had brought along a lens with a maximum aperture of f/4, and if that isn’t enough for the light you have available, then you’re in trouble. Similar problems can happen in controlled lighting scenarios as well. Contrary to popular belief, you can exhaust all your lights in a truck and still have insufficient light for the exposure you want.

Tough luck? No, plain unprofessionalism. Ever heard the phrase: Failing to plan is planning to fail?

I can understand cash-starved indie filmmakers making such compromises. I’ve done it, too. But a professional can never afford to make such a compromise. Imagine a doctor arriving at the operating table with stationary scissors.

It doesn’t mean the other lenses can’t get the job done, if you have enough light available. A professional has to take into consideration any contingency. What do you think Greg Toland and Orson Welles would have done if they hadn’t been able to achieve deep photography? Would they have abandoned Citizen Kane? Of course not, they would have shot at a larger aperture with shallow DOF.

Video production is too expensive to subject it to whims and ‘lucky breaks’. Directors and Cinematographers don’t have that kind of luxury. This doesn’t mean all lenses should be f/1, because that introduces a whole new set of problems. You’ll see many people extolling the virtues of an f/1.8 lens with a speed booster for an f/0.7 aperture – woo hoo – how many of these people actually have to pull focus with these beauties at f/0.7? It’s good to have, mind you, because you can also stop down an f/1.8 lens to f/2.8, but it is not necessary. Professionalism also consists in knowing when to stop – you don’t bring a jack hammer to hammer in a nail. Ask any professional who has tried – your ego will soon be cut down to size.

Step Two: List your shots

List all the shots you are likely to take (or need). This is mandatory on most productions anyway. For each setup or shot, I list the focal length and the f-stop. If you can’t decide, write down more than one (the second column in the below chart). It’s okay. This is what it may look like:

20121022-114404.jpgI use Microsoft Excel for all my spreadsheet work, but you can use a pen and paper too. You use experience, aesthetics, the location recce, photographs and your general knowledge of spaces to arrive at the right focal lengths. The first consideration should always be aesthetics, mainly lens draw, depth of field and bokeh.

The advantage of spreadsheets is that the next step becomes easier:

Step Three: Sort your shots

Sort the list according to focal lengths, and then do a second sort of f-stops within each focal length. It should look something like the table on the left:


You can quickly see how many times a given focal length is used, and what the maximum f-stop (minimum f-number) is for each focal length.

You could convert that into a graph (on the right), but it’s not necessary. However, the graph does drive the point home!

Important: Sometimes productions happen in schedules, and it might be a good idea to limit your lists within each schedule so you don’t lug everything around unnecessarily.

Step Four: Whittle down your list

From the chart or graph, you’ll be able to tell which focal lengths are critical, i.e., you’ll find your bread and butter focal lengths and apertures.

Here’s a rule of thumb: Invest more in your bread and butter focal lengths and apertures. You will need all your lenses anyway. The point is to find out how to distribute your time, attention and budget for maximum productivity and efficiency. E.g., in the above example, I know the 50mm is the most important focal length, and I need f/2. Zooms are out, so I will allot a good chunk of my budget for a really good 50mm f/2 (or better) lens.

This evaluation points out any lenses or apertures that are used for only one or two shots. Do you really need them? Can you make do without them? It forces you to streamline your thought process, and to be more objective in your selection. E.g., we can see that the 85mm lens is only used for one shot. Can we manage it with f/2.8? If yes, then we can club the last three focal lengths and just get one 70-200mm f/2.8 zoom.

In this way, you try to eliminate the obvious. The list will tell you whether a zoom lens or a prime lens might be a better investment.

Aesthetic criteria aside, here’s the rule: If you have a range of bunched up focal lengths with similar maximum apertures, then get one zoom lens that covers this range.

And here’s a corollary: If your focal length stands alone, or has a unique aperture requirement, get a prime.

Rinse and Repeat – eliminate every redundant possibility. You can ask all sorts of questions with this method. It is flexible enough to adapt to many scenarios or projects.

Once you have your ‘final list’ of focal lengths, shots and f-numbers, hunt for lenses that match your requirement. Don’t eliminate anything yet. Make a list of lenses corresponding to each requirement.

Step Five: Interrogate your lenses

Finally, compare the list of lenses with these questions (it’s not definitive, but it will give you ideas for your own productions):

  • Focus mechanism – do you need a follow focus system?
  • Aperture control – do you need de-clicked apertures for subtle exposure control?
  • Do you need weather protection?
  • Do you need creamy smooth bokeh, or a special quality of bokeh?
  • Do you need high acutance to shoot high-frequency fine detail like leaves, etc?
  • What kind of contrast do you like? Do you need artificial flare?
  • How do the lenses compare with aberrations and distortions?
  • Are you shooting fisheye or tilt-shift?
  • Do you need macro? If yes, can you get by with extenders instead of specialist macro lenses?
  • Can you use telephoto extenders instead of larger telephoto lenses?
  • Do you need autofocus or a servo zoom?
  • What is the size and weight of all these lenses? Will it fit my travel limitations?
  • Can I get filters to adapt to all these lenses, or will I be forced to buy a matte box?
  • Replacement, service, repair and warranty options – some manufacturers are better. Sometimes, you’ll find yourself forgoing a ‘better’ lens because the repair center is nowhere near.
  • Resale value – if you’re buying gear, you need to consider its resale value. Read Which is better, to buy or rent a camera? to know more.
  • Does my choices fit my budget?

Budget is last because it allows you to focus on your art. How? You will appreciate why the look you want requires an expensive lens. Sometimes, a lens you’re avoiding (possibly due to negative associations you’ve formed by reading some idiot’s advice) suddenly jumps out as being perfect for your job. You see, it’s not about image quality alone. You will come to have a clear idea of what compromises you’ll have to make to get a lens within your budget. This is what separates professionals from amateurs. Problem-solving is a critical skill in any professional’s arsenal, no matter which industry you’re in. A really good doctor may actually be able to perform a successful operation with stationary scissors. But he or she isn’t following blind luck, but doing it with full intent.

All said and done, only experience will make you better at estimating your requirements. If you’re at the beginning, my methodology will help you get started to know exactly what lenses you need and at what apertures. At least you can get started!

Will this make you perfect? No. Will it give you confidence? Yes, you bet it will. At the end of the analysis, you will be blessed with a manageable number of lenses from which to choose. If you know some tricks and ideas from your own experiences, please feel free to share them in the comments section below.

Do I really think and work like this? Yes, I use this methodology of reasoning and analysis even on smaller projects. Why not? It’s fun, and faster with a spreadsheet. Me and my spreadsheets.