Photographing Snow

8/13/2019 Photographing Snow

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Quick Tip: Photographing Snow

There’s nothing like a fresh snowfall to make a landscape truly dramatic! Snow is an inspiringphotographic subject, whether you’re shooting mountain vistas, or single flakes. But it’s also atricky subject – and many photographers find that the glowingly bright snow scene in front of

their lens mysteriously turns into a depressingly gray photo after they take the shot.This tipexplains why that happens – and how to avoid it -- for wonderful snow photos this winterseason!

In-Camera Metering Explained

The biggest challenge when photographing snow lies in your camera’s metering system.

Camera meters measure the light reflecting off of subjects in the frame, and use those measurements todetermine the appropriate exposure settings such as shutter speed, f-stop, or ISO. This system is universally

designed to render subjects as ‘middle gray’ or ‘18%gray’.

Just to clarify what that means: Middle gray isroughly the midtone on a gray scale – appearing tofall exactly between pure black and pure white.Subjects of this tone reflect about 18% of light(comparitively, white objects reflect nearly 100% andblack objects reflect nearly 0%).

Simply put, most cameras assume that everythingthey photograph reflects 18% of the light, andexposes accordingly. Put another way, your camerameters subjects assuming they should bephotographically rendered as middle gray.

Freshly-fallen clean, white snow is obviously muchmore reflective than that, and the camera willautomatically compensate by underexposinganywhere up to about two stops to correct for what it

sees as a too-bright subject. This is exactly why many photographers will find their snow photos to be muddyand underexposed.

In-camera light metering works reasonably well with most subjects, in most lighting situations. However, thereare tricky scenes that will baffle most meters – and snow is a classic example.

Dark subjects such as this antique car may fool the camera'smeter into overexposing the entire image, in an effort to render

the subject as 'middle gray' (minus exposure compensation canbe applied to correct this). (photo © Rudy Winston)

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Metering Modes

Most cameras have more than one metering mode (though they all use the basic reflective approachdescribed above). These modes are not always found in everycamera, but here are some of the common ones found in theCanon EOS and PowerShot systems:

Evaluative: Metering is directly linked to, and concentratedon, the active Autofocus (AF) point. Light values measured atthe active AF point are compared with light values measuredfrom the metering segments surrounding the active point, andthe camera's metering system attempts to provide anaccurate exposure based on that comparison. This meteringpattern is often effective when photographing people, but maynot be quite as effective when photographing snowylandscapes depending on other elements in the scene. Notethat because Evaluative Metering is linked to active AFpoints, focusing on a different subject may result in a verydifferent exposure – even within the same shot. Note: In thesimulated viewfinder below, Evaluative mode is shownwith the left-most AF point active.

Spot: This metering mode gets exposure information only from the single exposure zone in the centerof the frame (approximately 3% of the total picture area)

Partial: This metering mode is similar to Spot Metering, but covers a slightly larger area, reading only

the cross-shaped central five metering zones (approximately 10% of the total picture area) Center-weighted Average: This metering mode averages the exposure for the entire picture area, but

with greater emphasis on the center metering zones.

These are the common Meter Mode iconsused in Canon cameras (other manufacturersshould offer similar modes, but with othernames and symbols).





When using one of the EOS Creative Zone exposure modes (M, Tv, Av, P, A-DEP), you can select from anyof the metering modes offered on your camera. If you prefer to shoot in the Basic Zone exposure modes(Full Auto, Portrait, Landscape, Close-up, Action, etc.), the default mode is usually Evaluative. This is alsotrue in PowerShot cameras – although note that when Face Detection is turned on, any faces in the scenewill have exposure priority.

When photographing snow, any of these modes may be used effectively, depending on the overall scene. Forexample, if there is some contrast between the snow and the rest of the objects in the scene, then Evaluativemetering may be ideal because it will emphasize the exposure for whatever you are focusing on – even if it’soff-center.

If the overall scene is evenly lit and of generally even brightness, than Center-weighted Average willwork well to give a good overall exposure.

Spot and Partial metering will work well with subjects that have more extreme contrast, and/or when you don’twant one part of the shot to ‘confuse’ the meter. These modes are very useful when used in combination withthe Auto Exposure (AE) Lock button found on most digital SLRs. You can read more about that function here.

Unfortunately, even when the camera ‘accurately’ determines the correct exposure using the metering modeof your preference, with a subject like snow you are likely to see underexposed results. You can compensateby adding about one or two stops of exposure through Exposure Compensation in most of the Creative Zone

Darker red areas indicate the zones where the most metering emphasis is given within theoverall picture area. White areas indicate they are not metered at all (viewfinder is simulated

for reference only; actual camera viewfinder may look different by model).





AE modes (more on that below), or by using a slower shutterspeed, a wider aperture, or a lower ISO speed setting in Manualexposure mode.

Evaluative Metering mode is selected on thisEOS 40D (pictured above)





Exposure Compensation

Exposure Compensation (EC) is an easy way to get around your camera’s tendency to underexpose brightsubjects, and overexpose dark ones. It’s also very useful for photographers who are new to Creative Zoneshooting because it doesn’t require extensive knowledge of f-stops or shutter speeds. Exposure

Compensation is available in P, Tv, Av and A-DEP shooting modes only (in Manual 'M' mode, EC iscompletely disabled, and you have to make all exposure adjustments yourself).

Exposure Compensation lets you quickly add or subtract from 1/3 to 2 stops (up to 3 stops with some

Snow scenes with more contrast may benefit from EvaluativeMetering (the camera will expose for whatever you are focusingon), or even Spot or Partial Metering -- especially when combinedwith the AE lock function (photo © Rebecca Gurian)

Snow scenes with generally even brightness and contrast maybenefit more from Center-weighted Average Metering (photo ©Rudy Winston)





professional EOS models). You can also bracket several shots in arow, with each image of a slightly different exposure using the AutoExposure Bracket (AEB) function.

When photographing snow, you’ll want to experiment with addingmore exposure, anywhere from +1/3 to +2 stops EC may work, soplay around until you find what you like or try using AEB to ensurevariety in exposure levels.

Another approach is to shoot RAW images, which providesadditional control over exposure compensation on a computer(bonus: you'll be in the warm comfort of your home instead of out inthe cold!) However, understand that even when shooting RAWimages, it's necessary to start out with an exposure that'sreasonably accurate out-of-camera.

Correct underexposure with up to +2 stops ofEC, and the snow will look like it does to youreyes! (photo © Rudy Winston)





White Balance:

White Balance settings tell the camera what color temperature light source you are shooting in, so it cancreate the appropriate color cast for each scene. Most cameras have several automatic presets for commonlight sources: Daylight, Shade, Cloudy, Tungsten, Fluorescent, Flash, etc.

Many cameras also allow shooters to take a custom White Balance, or even dial in a specific colortemperature (measured in degrees Kelvin) to better match your scene, particularly for unusual or mixed-

In any of the Basic Zones: Exposure Compensation is notselectatable when you press the Av +/- button (such as on theEOS Rebel XSi, pictured above).

In Creative Zone modes: Exposure Compensation is indicatedon the LCD when you press the Av +/- button (such as on theEOS Rebel XSi, pictured above).





lighting scenes that are not covered by any of the preset optionsseen here.

Photographing snow implies you will be outside. However,differences in time of day, geographic region, and weatherconditions can make a huge difference in the color temperature ofyour light source – even though the ‘light source’ in this case isalways the sun -- which means that your White Balance may needto be adjusted, and the preset for 'Daylight' may not always look thebest.

The preset White Balance options are pretty accurate, but you haveto remember to use the one that most closely matches your lightsource, and weather conditions. For example, ‘Shade’ worksparticularly well on overcast days.

If you shoot RAW images, you can change your White Balancewhile editing, regardless of your camera settings at the time of shooting.

Watch your Highlights!

Another reason snow poses a challenge is because any white subject photographed in reasonably bright lightis at risk of losing detail with even slight overexposure. Worse yet, once a scene has overexposed highlights,there is nothing that can be done in photo editing to bring that detail back. Luckily, our current line of EOS

Most cameras offer several White Balance presets, as well as customizable WB optionsfor any light source.

Note the noticeable differences in tone associated with various White Balance (WB) settings.One of the benefits of shooting in RAW is that you can fully adjust the WB while processingyour files in programs such as Canon's Digital Photo Professional software -- so you can pickthe WB that looks best/most accurate/etc (photo © Rudy Winston)





digital SLRs offers a number of functions to help photographersavoid these unfortunate ‘blown out’ highlights.

Highlight Tone Priority

One easy-to-use, and very effective feature is Highlight TonePriority (HTP). This innovative Custom Function takesadvantage of the expanded tonal range found in newer EOScameras* to achieve up to one stop more detail in highlightareas – without effecting the overall exposure orunderexposing the rest of the scene.

HTP can only be used in the Creative Zone exposure modes,and once it’s turned on in the Custom Functions menu theeffect will automatically be applied to JPEG images in-camera

(for RAWshooters using Canon’s Digital PhotoProfessional: HTP is applied in processing).Please note that when HTP is active, the highestand lowest ISO settings of your camera may notbe available.

Histograms, and Highlight Alert:

In addition to Highlight Tone Priority, you can

also manage your highlights during playback: bychecking image histograms, and using theoptional Highlight Alert function.

A histogram is a chart that represents thedistribution of pixels in each image. It is visibleon therearLCDscreenduring

Live View shooting, or during playback, and is a veryuseful way to evaluate exposure. Histograms are sort of

mountain-shaped; the height of each peak indicateshow many pixels were recorded at particular brightnesslevels. The left side of the chart represents shadowareas; the right side represents highlight areas, and thecenter represents midtones.

Reading a histogram properly helps photographersdetermine the appropriate exposure for the scene, andwhether they are at risk of severe under- or overexposure. When photographing snow you arelikely to see histograms with many more pixels to the right of the chart, on the highlightside. This is completely normal when photographing bright subjects.

Highlight Tone Priority is a useful CustomFunction found on most of our current EOSdigital SLR cameras.

Histograms are a great tool when determingappropriate exposure, especially for tricky subjects suchas snow. Note here that the historgram is weightedto the right, indicating a brighter scene -- and thatnone of the pixels are getting cut off the chart,which means nothing is overexposed.

This histogram shows an image with alot ofmidtones, but no extreme shadows orhighlights.





However, if your histogram shows portions of the graph that appear to get cut off on the right, thatmeans portions of your scene are severely overexposing to the point that detail may be lost. Thisis a warning that your exposure should be adjusted. Try applying minus Exposure Compensation,

until you see that no part of your histogram is cutoff at the right edge.

Another way to check for overexposure duringplayback is with a feature called Highlight Alert.When active, this alert shows all portions of theframe on the verge of overexposing with ablinking indicator. This is an optional feature thatcan be enabled or disabled on most of our EOS

digital models – although Digital Rebels use it asa default during histogram playback.

Cold Weather Shooting:

If you plan to shoot outdoors in the cold for an extended period of time, please consider the followingprecautions to ensure the safety and functionality of your camera equipment:

Cold batteries die faster, especially in temperatures below the freezing point, so keep your batterieswarm. Carry them close to your body/in pockets/under clothes. Also, bring spares and keep those warmin your pockets until ready for use.

Give your camera equipment time to acclimate when goingfrom cold to warm temperatures. Otherwise, you riskcondensation build-up, which can damage lenses as well asinternal digital camera components. Gradually introduce it towarmer temperatures. For example, leave your equipment inthe garage or on a covered porch for a while before moving itinside.

Another trick to prevent condensation build-up when movingfrom cold to warm temperatures is to seal your camera in anairtight plastic bag (such as a Ziplock). Seal the cameracompletely inside of the bag BEFORE moving indoors, andcondensation should form on the bag rather than the camera.Leave the camera inside the bag until it's had a chance tofully warm up to room temperature.

If you anticipate mild snow or rain while shooting, waterproofyour camera with plastic bags. Bring lens cloths or lint-freetissues to wipe off any moisture that might build up on the

Highlight Alert indicates overexposure by blinking overthe areas of the frame on the verge of losing detail.





lens from melting snowflakes. Invest in fingerless gloves with a fold-back mitten top, so you

can access camera controls while keeping your hands aswarm as possible in between shots.

* As of January 2010, Highlight Tone Priority (HTP) is offered on the EOS Rebel XSi/T1i,EOS 50D/40D, EOS 7D, EOS 5D Mark II, EOS-1D Mark IV/Mark III and the EOS-1DsMark III cameras.

To avoid condensation build-up on yourcamera, try placing it in a sealed plastic bagwhen transitioning from cold to warmenvironments -- moisture will be on the bag,instead.


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Photographing Snow