Plugged In: Low light presents high challenges

By Joe Kashi, for the Redoubt Reporter

What’s required to take good photos of family and friends under near-dark conditions?

While speaking at a law office technology conference in Canada last week, I ended up as the de facto photographer at several after-conference dinners and social gatherings where the lighting conditions could only be described, charitably, as awful.

At one 20-person dinner, the only light came from some candles on the table and a few business signs across the street. At a speaker’s gathering the next evening, the primary light came from an illuminated fish tank whose LED lights had a purplish cast while the only other light came from a few kitchen track lights that strongly illuminated one side of guest’s faces. That resulted in very harsh, high-contrast lighting. These are the sort of conditions that you’ll likely encounter during family gatherings over the holidays.

Balancing light of differing colors is hard enough, and that difficulty is magnified when the light is very dim and highly directional. Generally, I prefer to use a camera’s lowest ISO sensitivity, usually termed the “base sensitivity.” When light conditions are adequate for normal photography using medium apertures and fast-enough shutter speeds, you’ll usually get better photographs when exposing at base sensitivity. Noise is lowest, sharpness is somewhat better and dynamic range is highest.

As you increase the ISO setting to compensate for dim light, a camera’s potential image quality inevitably declines, although some cameras start showing degradation more quickly. Modern cameras usually do better in very dim light than older models, as do cameras with larger sensors. More so here than in most situations, equipment choice makes a noticeable difference.

Although you can use an electronic flash, I prefer to use “available light” and avoid flash for several reasons. Using flash is more likely to produce unnatural-looking results with inky-black shadows and blown-out facial detail. Most on-camera flash units are effective only over very short distances, on the order of 6 to 8 feet, with brightness that drops off precipitously.

Moreover, that energy put out by your camera’s built-in flash unit as bright light needs to come from somewhere — in this case, your camera’s battery. As a result, the battery runs down far more quickly when also powering a frequently used flash unit. Did I mention, by the way, that the camera I brought along does not have a built-in flash and that I forgot to pack its clip-on flash unit?

Regardless of the ISO sensitivity, you’ll absolutely need to use image stabilization to avoid the camera-shake blurring that otherwise ruins dim-light candid photos. Even at ISO 3200 with a very bright, f/1.7 prime light, I found that I needed to make exposures at one-quarter to one-half second. That’s too long to hand hold the camera without really effective image-stabilization hardware. Typical image-stabilization hardware may be useful as long as one-sixth to one-eighth of a second, depending on your lens’ magnification, but that’s stretching its capabilities. Even with the excellent image stabilization built into my Olympus OM-D, I found that many images shot at one-quarter second or slower showed some subtle, or not so subtle, reduction in sharpness caused by the subject’s motion.

The bottom line is that you need four hardware features to take good candid shots in very dim available light — a camera that’s not too noisy, bulky or otherwise obtrusive to use during quiet social gatherings, good high-sensitivity performance at ISO 3200, excellent image-stabilization hardware and very bright prime lenses with maximum apertures in the f/1.4 through f/2 range. A few camera lines fulfill most or all of these requirements.

  • Large-sensor cameras, particularly current-model, full-frame cameras from Nikon, have excellent low-light image quality and a wide array of fine bright prime lenses, but full-frame cameras are big, black, bulky and heavy, not to mention expensive. Large prostyle cameras are not particularly comfortable for either the subject or the photographer when used in social situations.
  • Compact consumer-grade cameras, cellphone cameras and tablet computer cameras are quite incapable of working well in very dim light because of their very small sensors and slow lenses. Medium-sensor premium compact cameras, like Sony’s RX100, are suitable in marginally dim light, with the RX100’s four-times larger sensor giving it a significant edge. While the RX100 is a reasonable choice for some less-challenging situation, it’s quite expensive and hampered by an optically marginal fixed zoom lens. The 1/1.6-inch sensors found in premium compact cameras like the Canon S120 and Panasonic LX7 have noticeably reduced image quality by relatively modest ISO settings, like ISO 1600, but may be quite adequate if the light’s bright enough. They also have a built-in flash, with its attendant drawbacks.
  • Better APS-C digital SLR cameras, such as any of the Pentax K-5, K-30 and K-50 cameras, Sony A58, or Nikon’s D5100/D5200 and D7000/7100 series, have excellent available-light image quality, bright lenses and useful image stabilization. They’re usually not quite as bulky as full-frame cameras. Any of these dSLR cameras would be my first choice, except that their bulk and weight may become obtrusive during casual social gatherings. Whether they are too bulky and obtrusive is probably an individual choice in this range.
  • Panasonic’s excellent GH series cameras meet our criteria, except that the GH series cameras have the same bulky obtrusiveness of APS-C dSLR cameras. All other Panasonic Micro Four-Thirds models, as well as earlier 3-series Olympus M 4/3 cameras, use a 12-megapixel sensor that’s too noisy when used at any sensitivity higher than ISO 800 to ISO 1600. Only Panasonic’s newest GX7 model includes the built-in image stabilization hardware that allows it to use Panasonic’s own bright prime lenses to full advantage in dim light situations.
  • Sony’s quite compact NEX series cameras, which also use very good APS-C sensors, would also seem to fit the bill but are hampered by a lack of affordable, image-stabilized prime lenses with bright maximum lens apertures in the f/1.4 to f/2 range. Fujifilm’s X-Pro, X-E or X-M models provide good image quality through ISO 6400 but, again, suffer the same current lack of bright image-stabilized lenses, which more than offsets Fujifilm’s excellent high-ISO performance. These factors basically limit your optimum dim-light choices to current-model compact-system cameras. The best choices seem to be any of Olympus’ E-P5, E-PL5 and E-PM2 Pen cameras or E-M5 models. The Olympus cameras are small, quiet and do well up to ISO 3200. Their built-in image-stabilization hardware, particularly the five-axis magnetic suspension system used in the E-P5 and E-M5, provides excellent anti-shake capabilities at very slow shutter speeds, even when using Olympus’ and Panasonic’s excellent and bright — but unstabilized — prime lenses at very show shutter speeds. All of the listed Olympus models use the same 16 high-quality M 4/3 sensor, so you’ll not find much difference in low-light image quality between models. Your choice will depend more on your budget versus desired features.
  • That brings us to suitable lenses. The kit zoom lenses that ship with basic camera packages are generally too slow to be effective in dim light, with maximum lens apertures starting at a relatively dim f/3.5 and only getting worse as you zoom toward higher magnification settings. Thus, good single magnification “prime” lenses with a moderate, wide-angle field of view are the best choice here, preferably with bright maximum apertures in the f/1.4 to f/2 range. It’s a real bonus when those lenses are very sharp at or near their brightest aperture. I’ve been using Panasonic’s 20-mm f/1.7 lens and Olympus’ 17-mm f/1.8 lens most often in these situations. Both lenses are bright, are sharp at or near their maximum aperture and are very compact and light while being reasonably affordable, with list prices in the $40 to $500 range.
  • Careful technique is very important in these situations. It’s also helpful to take a lot of images in order to pick the best ones. Inevitably, you’ll need to use very slow shutter speeds, even at high sensitivity settings like ISO 3200, so blurring from camera shake and subject motion is the biggest challenge. Balancing harshly directional, often weirdly colored available light requires some post-processing work in Lightroom or Photoshop, but that’s a subject for another day.
  • Security alert! Adobe Corporation recently admitted that it was hacked and that about 3 million accounts were compromised, including names, passwords and credit card information. Although Adobe claims that it sent out emails to everyone, no one that I know has received that email. Here’s why this is a potentially serious problem. Adobe requires that everyone who wants to download any product — including trials, updates and upgrades — have an account with Adobe, even if they don’t make a purchase transaction. Most people tend to use the same password across several Internet accounts.  So even if Adobe did not have your confidential or credit card information, your login and password have been compromised, which might have a ripple effect involving your other web accounts where confidential and credit card information is stored. Change all of your passwords on every website. Monitor your credit card for unusual or unauthorized activity.

Local attorney Joe Kashi received his bachelor’s and master’s degrees from MIT and his law degree from Georgetown University. Many of his technology and photography articles can be accessed through his website, http://www.kashilaw.com.

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Filed under photography, Plugged in

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