Plugged In: Lighten up — Shooting in tough conditions

By Joe Kashi, for the Redoubt Reporter

Photo by Joe Kashi, for the Redoubt Reporter

Photo by Joe Kashi, for the Redoubt Reporter

Our readers recently raised several questions that may be of general interest, including how we prepared our baby moose photos for print in our May 29, 2013, issue and whether to buy a Canon Digital Rebel dSLR rather than some other brand.

One reader noted that our photos of the baby moose were actually shot under adverse lighting conditions and inquired how we obtained images that were usable in newsprint, which doesn’t reproduce photographs very well. That reader’s observations were apt. We had to use whatever older camera gear was on hand in the car when we spotted the cow and newborn calves. We didn’t have time to drive around and get our best gear. Because the cow moose was carefully guarding her young some distance into a large field, we didn’t want to approach and disturb her — nor get stomped, for that matter.

That clearly meant using a high-magnification telephoto lens from the roadway. Unfortunately, that also meant using an old dSLR camera and an inexpensive telephoto zoom lens that’s fairly soft at its 300-mm highest magnification, shooting the shadowed side of a dark animal backlit by a strong sun. That’s a potentially difficult combination.

Here’s what we did. Changing location and angle of view wasn’t possible, so we simply used that soft, 300-mm magnification setting and planned on some post-processing. We set the camera so that each press of the shutter button actually resulted in a set of five widely bracketed exposures using an RAW file format, knowing that one photo from each set would have better shadow detail and that RAW would capture more potentially useful detail. We increased the camera’s ISO sensitivity to 800 in order to use the lens at a smaller aperture, f/11, where we knew from experience that the lens wasn’t quite as soft at the 300-mm setting. Using the higher ISO setting also allowed a shutter speed sufficiently fast that camera shake was not evident, despite handholding the camera at a high magnification setting, equivalent to a 35-mm camera mounting a 450-mm supertelephoto lens. Image-stabilization is certainly needed when handholding a camera at such high magnifications.

As a practical matter, despite some increased image noise and decreased sharpness, it’s usually worthwhile to increase ISO sensitivities if needed to use a sufficiently fast shutter speed and an aperture where a lens is sharper. Most inexpensive lenses are usually sharper when set to an aperture setting that is two or three full stops darker than maximum aperture. In this case, my old zoom lens has a maximum aperture of f/5.6 at its 300-mm magnification, so a two-stops-darker aperture, f/11, helped produce an acceptably sharp image, but doing so required a higher ISO sensitivity in order to avoid camera shake, even in bright sunshine.

Adobe Lightroom is one of the most easily used and powerful photo programs in general use and also allows easy processing and resizing of an image to fit printing requirements. From our bracketed images, we chose examples that seemed somewhat overexposed on first impression because good shadow detail was critical here. The subject was backlit and inherently dark, so increasing exposure to favor shadow detail was the best approach.

We then first used Lightroom’s “Shadows” slider to generally increase shadow brightness and detail, particularly in the dark hair of the moose, and then set the “Highlights” slider to a negative setting of -90 in order to tone down the brightness of the overexposed field areas behind those backlit moose. Increasing the “Clarity” slider from its default setting of 25 to 60 allowed us to increase microcontrast to bring out fine shadow detail, which would otherwise have been muddied by the low-end lens that was in my car’s go-anywhere kit. Similarly, we set the “Sharpness” slider to a 2.0-pixel sharpening radius, probably the best compromise for this lens, and increased sharpening from its default setting 25 to 80. No noise reduction was needed because images made in bright sunshine are usually not very noisy. We set the “Lens Correction” panel to remove Chromatic Aberration and to use Adobe’s built-in correction profile for that specific lens. Finally, we cropped the images to taste and exported them as JPEG files, increasing contrast to compensate for newsprint’s lower contrast and reducing the image’s size from 4400 pixels on the long edge to 1320 pixels. Not only did that size reduction fit the image to the printer’s requirements, but reducing its size also made any residual unsharpness less evident.

This level of correction was feasible because the photos were taken with a dSLR camera, whose large, APS-C sensor has greater dynamic range and because the images were saved in an RAW file format, which preserves more highlight and shadow detail than regular JPEG files. JPEG photos taken with a small sensor superzoom camera would probably have been more problematic.

That leads us to our next reader inquiry, which asks whether a Canon Rebel dSLR camera would be a preferred purchase.

Our response: These cameras are very popular and have made many fine photos. However, even though Canon’s new STM IS kit zoom lens is quite decent, Canon’s APS-C dSLR cameras in general have been lagging technically over the past few years in terms of sensor performance as objectively measured by DXO. You can find and compare DXO’s comprehensive and widely accepted objective camera sensor data at http://www.dxomark.com. Canon makes its own sensors rather than buying them from industry leader Sony, which supplies state-of-the-art sensors to Nikon, Pentax, Olympus and its own Sony camera lines.

Sensor performance is particularly important because a dSLR’s sensor is the camera’s single most critical component, and it’s not replaceable. You can update a camera’s features through firmware updates or acquire a sharper lens, but you can’t change sensors and thus can’t alter a camera’s fundamental image quality. That requires buying a new camera body with a better sensor.

Canon currently offers a variety of dSLR cameras using standard-sized APS-C sensors. These include the T4i consumer model along with its newer replacement, Canon’s T5i, as well as the more expensive 60D and 7D models intended for enthusiasts and light professional use. All of these APS-C cameras perform identically in the DXO tests, but more poorly than comparable Pentax, Nikon, Sony and Olympus cameras, generally by a significant amount. Canon’s suboptimum consumer sensor performance is particularly evident in their poorer lowlight capability and in dynamic range that’s as much as two stops lower than similar cameras from other makers. That reduces overall versatility.

Unless you already have some good Canon lenses and have bought into Canon’s lens mount system, I would instead consider one of Nikon’s APS-C models, the Pentax K30d, or any of the Pentax K-5 models. The Pentax K-5 models and Pentax K30d use Sony’s superb 16-megapixel APS-C sensor, very likely the best APS-C sensor ever used in an affordable camera.

The K30d (about $550 new, body only) and the original K-5 (still available new at Amazon.com for about $700 body only) are both affordable and very competent, weather-sealed, dSLR models suitable for serious use. Both are excellent deals for very rugged, well-thought-out cameras. (Remember, both camera and lens must be weather-sealed if you’re to avoid environmental damage when used in adverse conditions. We’ll explore weather-sealed lenses in a future article.) Among professional reviewers, even diehard Canon users find themselves quite impressed by any of the K-5 series cameras. The Pentax K-5 II is a newly introduced, somewhat upgraded version of the original K-5, about $1,000 body only, but the original K-5 does just as well for less money. It’s definitely the best deal around for a rugged, prograde dSLR camera. Rather than Pentax’s kit zoom lens, get a copy of Tamron’s supersharp 17- to 50-mm f/2.8 (non-VC) zoom lens, which usually sells for about $400. This lens is so good that it’s money well-spent, even if you have the Pentax kit zoom.

Any of Nikon’s APS-C, consumer-grade SLR cameras would do very well. I tend to somewhat prefer Nikon’s older 16-megapixel D5100 and D7000 models, rather than the newer 24-megapixel D5200 and D7100. Sony’s A58 is nice and it’s affordable, but Sony’s optical product lines tend to lag compared to Pentax and Nikon. Nikon’s D7000/7100 series cameras are weather-sealed and built to the same standard as the K-5 series.

If you don’t insist on a traditional, moving-mirror d-SLR with optical viewfinder, then the Olympus E-PL5 mirrorless camera, usually sold with above-average 14- to 42-mm kit zoom lens (28- to 84-mm equivalent), is an excellent buy at its current $550 price with kit zoom lens, and despite its slightly smaller sensor, actually outperforms the consumer-grade Canon dSLR cameras in terms of image quality, particularly in dim light when using a fast “prime” lens. The E-PL5’s dynamic range is better, as well.

The Pentaxes and Nikons mentioned here do better in terms of image and build quality compared to Canon Rebels. The Pentax K30d is a better buy, more solidly constructed, smaller and lighter, but Nikon’s consumer dSLR cameras have access to a wider range of lenses. For what it’s worth, I shoot an older Pentax K-5 for more serious work and various Olympus cameras (mostly the OM-D, which uses the same sensor and processing chip as the E-PL5) when I want to travel light.

It’s a different situation in the zoom-lens premium-compact camera product lines. Canon’s premium compact offerings, like the G15, large-sensor G1X and highly pocketable S100/S110, tend to be more practical and useful than Nikon’s directly comparable products.

Attorney Joe Kashi received his bachelor’s and master’s degrees from MIT and his law degree from Georgetown University. He has published many articles about computer technology, law practice and digital photography in national media since 1990. Many of his technology and photography articles can be accessed through his website, http://www.kashilaw.com.

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