Saturday, September 30, 2017

Winter Light-Getting the Exposure Right by Joe Rakoczy

Forget what the calendar says. For Upper Midwesterners winter arrives early and leaves late. The further north you travel around the Great Lakes, the longer winter sticks around - and the better the opportunities are for photographing ice and snow.

Winter can transform the landscape beautifully.  Snow covering tree branches and blanketing the land can appear magical. The solitude and quiet can be stunning.  You may find yourself all alone in spots overrun with people in warm weather months.  (And vice versa, if there’s a winter festival on a frozen lake or a dogsled race through a forest.)  And, of course, there are no mosquitoes (or ticks, or horseflies, …)

While winter days are shorter, the sun stays lower and the longer daily periods of   “photographer’s light” can lead to outstanding photography. Skies are often a deeper blue. Textures can be more pronounced.  Even on cloudy days, a blanket of snow creates a massive light reflector that better illuminates trees, rock faces, buildings, people and animals.

But among the challenges of winter photography, capturing that winter light and properly exposing for snow and ice while still revealing important detail and texture in the snow and other elements within your image, ranks as one of the toughest. 

Mid-day sunny conditions, glare off snow, and backlit ice, can fool your camera’s light meter into underexposing images, resulting in unappealing dull, dark or gray tones.  Why does this happen? Your camera’s meter is designed to capture an average medium gray exposure at normal camera exposure settings. If your camera’s viewfinder is filled with a completely black subject like a non-reflective black wall, without upping either your aperture (using lower f-stop) or lowering your shutter speed or decreasing your ISO/sensitivity, your image will be a middle gray instead of black.  Same goes if you aim it at a completely white wall. 
So you need to find a way to take control and override or “trick” your camera’s meter into getting the exposure you want.

Shooting in Raw instead of only JPEG, makes much more sensor data available (as indicated by Raw image files being much larger than JPEG files), enabling you to correct many image exposure and color rendition problems in post-processing.   So for serious photography we recommend you shoot in raw (plus JPEG).  Note that virtually all raw images will require imaging editing on the computer using raw conversion software such as available from your camera’s manufacturer, or in Photoshop Elements, Photoshop, and Lightroom.    

But whether or not shooting in raw, getting the best image capture in-camera is the way to go, assuring you the best opportunities for creating excellent images.

Listed below are some things you can do - individually or in combination - toward getting a correct exposure of snow and ice scenes.

By the way, for our more serious winter landscape photography we typically shoot using tripods with our DSLR cameras set on aperture-priority mode (camera “A” mode setting). Typical aperture setting is our lens’ “sweet spot” f-stop setting (aperture yielding the sharpest focus), which is about f11, or for more depth of field, f16 or f18.

Increase exposure   While many/most modern cameras with multi-point metering (e.g. 51 point matrix) often achieve fairly accurate snow scene exposure, if most of your viewfinder is filled with bright snow or there’s a lot of glare anywhere in the frame, you’ll need to – and this seems counterintuitive - increase your exposure from what your camera gives. Set your exposure value compensation (EV +/- button and slider) between ½ to 2 f-stops higher than your camera indicates.  In playback/review mode, immediately look at your LCD screen to check your exposures and re-adjust the EV compensation accordingly if necessary.

Bracket exposures  Take multiple shots over a range of exposure settings in 1/2 or 2/3 f-stop increments.  Many camera models have automatic bracketing allowing you to preset your camera for uniform shooting of three, five, seven or nine total shots at different exposures. Bracketing this way just about guarantees you’ll get at least one good exposure.

Use your histogram  In playback/review mode, check your image’s  tonal/luminance histogram on your LCD screen.  The histogram is a graph showing dark tones on the left and light tones on the right. Adjust exposure value (EV) compensation {the button for it has this symbol: +/-} and reshoot if necessary to keep the curve to the right but without climbing the right side wall, which would indicate hot spots/blown out details.

Use your spot meter  Most DSLRs have a spot meter camera meter function allowing you to take a light reading off a single small area within your frame instead of the entire frame.  Choose a point that’s in the same light as your subject and that’s approximately a medium gray like a lighter part of a blue sky, or a medium toned tree trunk, jacket or backpack/camera bag.  Either hold the exposure button down if your camera has one and take the shot, or check the reading and switch to manual mode to set the same settings.

Use an 18% Gray Card This is pretty much and adjunct to the previous tip. Buy/borrow a gray card from a camera store. Hold it in approximately the same light as your subject and shoot at the same settings as the reading off the card.

Shoot in HDR (high dynamic range) For very high contrast lighting conditions where the camera can’t capture the wide range of tonal values within the scene (as indicated by not capturing the entire histogram curve within its boundary walls), shoot in HDR. Using a tripod or other support, bracket exposures as described but save the exposures and use them in HDR software such as Photomatix Pro, Nik HDR Pro, or Photoshop.  Some modern cameras allow for in-camera HDR shooting and image processing.

Shoot Raw Repeating it again here for emphasis: shooting in raw affords you the widest exposure latitude and best white balance adjustment capability in post-processing.

Using the above camera techniques should lead to getting the exposure you want.  Keep in mind though that they all globally affect your images.  With many of your images you may find yourself having to selectively tone down or brighten certain areas using image editing tools. 
-----------------------------------------------
Side Note: Going retro - in the pre-digital days of film cameras, if your camera didn’t have a light meter or you didn’t have a handheld meter, or its battery died, you might resort to using the Sunny Sixteen Rule. (Remember with film there is/was no instant gratification image playback/review mode. You’d generally have to wait days to see if you got a correct exposure.) This rule of thumb was fairly accurate.  For sunny day brightness with harsh shadows, and your camera set at f16, and no light reducing filter on your lens such as a polarizer, you’d shoot at a shutter speed of 1 over your ISO (it was ASA back then).  So if your ISO was 100 you’d try shooting at 1/125 second (1/100 wasn’t a standard setting) at f16.
Copyright ©2017 Joe Rakoczy


Joe and Marie Rakoczy are avid photographers and especially enjoy cold weather photography. They’ve produced a number of travelogues as well as several educational programs. Both are TOPs in CACCA winners and Joe was the recipient of CACCA’s 2016 Wanda Crystal Award for photographic and artistic excellence.  Marie was the first PSA Chicago Chapter recipient of the new PSA Portfolio Award.  Their articles and photos have appeared in several publications, including an article about winter photography entitled "The Magic of Lake Ice" in the December PSA Journal.

Joe and Marie will be presenting "Winter Up North" a how to prepare for and photograph the beauty of winter at CAPS on Saturday, November 18th.

To see the entire schedule of classes go to: caps.caccaweb.com or click here:  Home

To register go to:   Chicago Area Photographic School (CAPS) 2017 | Summary | powered by RegOnline


No comments:

Post a Comment