Wide Angle Lenses - How to choose, How to use

Topic

Interested in wide angle photography?  This article walks though how to use a wide angle lens and how to shop for one.

What is a wide angle lens?  Let's literally take a look:

In the photo above, the outer blue box shows the view from a wide angle lens (a 15 mm full-frame equivalent with a 110 degree field-of-view).

The inner blue box shows the framing you would see from a typical cell phone camera if you were standing in the same spot. (40 mm equivalent with a 56 degree field-of-view)

With this example cell phone, you could back up to get more rocks and shore but this is not going to give you the same image as the wide angle.  For starters, the distant shoreline won't change much in size when you move back, making it much larger in the 40 mm than it currently is in the 15 mm version.  Essentially, the relative sizes of all near and far objects will be less different with the longer lens.

Thus the only way to get the same wide angle image with our example phone camera would be to do a panoramic stitch.

Uses

The main uses for a wide angle lens are:

Landscape

Canon Beach - taken with a 15mm lens (APS-C) with an 88 degree FOV

As shown above, a wide angle lens can capture more of the overall landscape scene in a single image and thus provide a "different" look than what most people can achieve with their phones or travel cameras (unless they do a panoramic shot and these don't always work out well).

Interior

Wide angle lenses give interiors a feeling of "spaciousness" (15mm image shown)

Wide angle lenses also make car interiors look larger, as this 11 mm image shows.

Real-estate photographers usually opt for wide angle lenses when photographing interiors because the exaggerated perspective creates a feeling of spaciousness - making rooms appear larger in photos than they will in person.  Car interior photos are often wide angle for the same reason.

Architecture

A wide angle lens was used here to help show the scale and complexity this old railroad avalanche shelter

Architecture photos often use wide angle lenses, both for practical reasons (limitations on where the camera can be placed with a clear view), and because wide angle lenses give more options for cropping.  Cropping (or shifting) is needed when the photographer wishes to avoid keystoning effects.

An example of "keystoning" where angling the camera causes parallel lines to angle toward one another.  If this is not the desired effect, shooting the scene with a "leveled" camera, then post-cropping is one strategy.  Using a wide angle lens can help.

Less Popular Uses

To start, I'll say you can attempt to use any lens for any purpose but the following uses "go against the grain" and thus enter the realm of creativity.

• Close Portraits: To get a person to "fill the frame" with a wide angle lens, you have to get the camera very close.  This creates personal space challenges which can make many people less comfortable.  The other potential problem is that the resulting image will reflect the close perspective, rendering a larger nose, smaller ears, and a unusually-shaped head.  Although this can be a fun way to be creative, people usually prefer traditional methods.
• Macro or Product:  It's quite common for a wide-angle lens to be able to focus very closely, even an inch away from the front of the lens.  Outside of exaggerated perspective, the issue here is the effect of the camera lens on lighting - the lens can actually block useful light from reaching the subject!

Issues, With "Work Arounds"

Wide angle lenses are a challenge to use well and come with many inherent compromises.  This section attempts to cover the major ones.

Distracting Elements In The Frame

Because wide angle lenses capture so much in a single image, it can be a challenge to keep distracting elements out.  This can especially be difficult when starting out under a "single subject" compositional mindset.

My advice here is to shift compositional thinking to "whole image".  This means first looking for a favorable wide-angle environment, then looking for specific subjects after that.  I highlight some specific examples below:

A beautiful sky is a nice time to go with a wide angle lens.  The sky can cover a good portion of the frame in a complimentary way.  Water is another good compositional component for the same reason.

Oftentimes, the sky is not interesting enough to deserve space in the frame.  In this case, consider minimizing it in favor of more landscape elements.

Large areas of a given pattern can work well to simply an image and avoid distracting elements.

Finding A Subject

If your photo is built on a singular subject, you'll often have to get close to that subject or it will be too small to "stand out".  Some tips for doing this are shown in the images below.

Getting the camera very low to the ground allows small objects to be used as a subject

Another option is to allow the subject to be small and build the composition to embrace this smallness

With natural subjects, such as trees, it's often possible to get very close without the resulting perspective distortion becoming bothersome.  This image was taken with a 10mm fisheye lens at a very close distance.

Subject Background Balancing

Background objects taken with a wide angle lens become very small, almost too small to be a part of the photo.  Because of this, distant features such as mountains should mostly be considered an "inconsequential" part of the composition.  Foreground objects and sweeping objects (sky, landscape) need to mostly carry the image.

An image of Mt Rainier with a 100 mm lens.  Long lenses make it easier to include background elements, although this feature can bring  with it a sense of two-dimensional "flatness" to the image. 

An image captured from the same shoreline with a 15mm lens.  See how Mount Rainier in the distance (left of center) has become nearly irrelevant to the composition?  Anything not close up or vast in wide-angle tends to become marginalized.

Distortion

It took me a while to realize this, but distortion can mean a combination of several separate issues:

• Lens distortion:  This is a tendency for lenses to make straight lines look curved.  On some wide angle lenses, it's complex where lines in certain dimensions (say parallel to the frame) are straight where others (say toward the camera) have a curve.
• Perspective distortion:  This is a natural distortion where objects that are actually to the side of the camera suddenly have to be projected onto a flat rectangle.  The result is strange-looking bending and warping near the edges of the frame.
• Keystoning:  Oftentimes the effort of getting a good composition means tilting the camera up or down.  This action causes straight lines to bend toward or away from the frame.  The keystoning effect is not limited to wide angles but tend to be exaggerated by them.

Some examples:

Note the severe unnatural bend of the boat masts on the right.  This is a combination of perspective distortion and keystoning (angling the camera upward)

Another example, where boat masts become progressively more angled to the right of the fame

One workaround for these problems is to simply go a little less wide as the issue becomes increasingly harder to keep under control as you go wider.

Another is to try and place objects without obvious proportions nearer to the frame edges.  Natural objects like water, rocks and trees tend to work well.  Man-made objects like buildings and signs make it more obvious that something is "off".

A third method is to try and keep the camera level to minimize the effect, perhaps with some post cropping after-the-fact.  This is a trade-off that you'll have to apply your artistic discretion toward.

Finally, you can simply embrace the effect, even try to exaggerate it - it's all subjective opinion at the end of the day, after all. :)

Field Curvature

Although it's natural to think of a focus plane as a flat plane in space, in reality it's never quite so simple. Wide angle lenses, in particular, have quite a difficult time keeping the focus plane "flat" (to varying degrees).  Also note that this curvature is a part of the design compromises in the lens, swapping copies of the same lens model is a frivolous exercise.

Why does it matter?  Mainly because you need to be careful how you focus.  If you don't then you can expect problems like soft corners that can otherwise be avoided.

To address this issue, you will have to see if and how much it's a problem for your lens.  If it's a problem, you'll have to experiment with what part of the frame you use for focusing.  For my favorite wide-angle, the "recipe" for best overall landscape focus is to focus about 1/4 away from the bottom corner of either frame.

What To Look For

This section talks about things to consider when purchasing a wide angle lens. 

Flare Can Be A Problem

By their nature, wide angle lenses capture light from many angles.  Designing a lens that keeps flare low in these situations is a challenge that many lenses (even expensive ones) don't meet too well.  To make matters worse, lens hoods often have to be sparse to prevent vignetting issues.

The best way to determine if a lens has too much flare is to rent or borrow it and decide for yourself.  You can also check a review site like lenstip.  Finally, you can visit a "samples" site like pixelpeeper or flickriver.  On these sites, you can choose the lens you are interested in and check out images with the sun or bright lights.

Don't Forget About Filter Support

Filters are quite useful in landscape photography.  ND filters can allow for long shutter speeds, showing the flow of things like leaves and water.  Polarizing filters can reduce glare on objects, improving color and clarity.  Even color filters are still useful in digital if you are using advanced techniques (like RGB channel balancing with ETTR).  We won't cover details in this article...

The issue I'm getting to here is that many wide-angle lens designs use a "bulb shaped" front element.  This design can improve sharpness but filters are difficult and often expensive to mount, requiring creative after-market approaches.

The Nikon 14-24mm is a lens of legendary sharpness.  Unfortunately it's flare resistance is only "OK" and adding filters to the bulb-shaped element requires expensive after-market workarounds.

The Pentax 15 mm contrasts the Nikon 12-24mm in nearly every respect.  Image sharpness is good, but not "legendary".  Then again, the flare resistance is excellent and inexpensive 49 mm filters can be easily attached.

Note that polarizers don't work too well on very wide angle lenses of any type due to the extreme light angles.  This leads to vignetting on the edges of the frame.  For moderate wide angle lenses, they are fine.

Good Manual Focus > Auto Focus

At least for most people.  The reason is that the depth of field is so large on wide angle lenses that zone focusing is effective.

This Sigma 10-20 has a "high speed internal motor".  I prefer a great manual focusing experience for this type of lens.

The Zeiss 21mm is $1800 and is manual focus only.  It's a very nice manual focus too...  Too bad the lens flares a bit too much.

Another reason is that, due to field curvature, you'll probably want to focus using magnified live view.  Manual focusing benefits from a long focus throw which autofocus lenses generally do not have, making live view focusing more precise.

For the reasons above, many of the most expensive wide angle lenses are manual focus only.

Focus Scales Are Nice

A lens with focus scales is nice with wide angle because you can "learn" what scale positions work well for certain shots.  This can save time and also provides a sense of confirmation that things are setup correctly.

No focus scales on the Sony 16-35mm.  This means there is no way to zone focus the lens and you'll have to do your best with the LCD.

Weather Sealing Is Nice

Although uncommon in less-expensive lenses, weather sealing is a nice feature in any lens intended to be used in outdoor landscapes

Weather sealed with focus scales and filter support.  A strong contender :)

Wide Angle Zooms Can Be Tough To Master

Basically, all wide angle lenses have their "quirks" like field curvature, flare, etc that you have to learn to predict and work around.  With a zoom lens, these quirks often vary by focal length, making it even harder to pre-visualize your results.

The complexity of zooms might also make decentering a higher risk as there is simply more that can go wrong.

I also found that it's not always obvious which wide angle focal length to pick.  For these reasons, I have gravitated to primes when using wide angles.

Software Stitching Can Emulate Wide Angle - Sort Of

In modern times, you can also put your camera (with a regular lens) on a tripod (or even handheld) and photography many images in a grid.  You can then use a tool like Hugin or Microsofts Image Composite Editor to stitch them together - and both tools are free!

The downside is that making a wide angle image this way is a lot more work.  Another problem is that movement in the frame can create big problems, even ruin an attempt completely.

Summary

Wide angle lenses can be a real asset and are quite a bit of fun to use.  That said, they are specialty lenses and often bring more problems than benefits in a "typical" photography scenario.

If you are interested in wide angle, my advice would be to rent before you buy and get a feel for what it's like to use such a lens.  I'd try a few from primes to zooms, even a fish eye, and simply see if it's something you enjoy.  Have fun!