By Joe Kashi, for the Redoubt Reporter
To unfold and blossom, your photographs of intense fireweed require not only proper focus and good depth of field but also optimum exposure. That’s our topic this week.
- Before we proceed, though, don’t forget to enter the Redoubt Reporter’s two summer 2015 photo contests, with cash prizes for each of the two summer photo contests totaling $350, publication in the Redoubt Reporter, and later exhibition opportunities. There’s no fee but the Aug. 21 deadline is fast approaching. Go to www.artspaceak.org for complete details and entry forms.
Finding that optimum exposure can be a bit tricky. The intended final appearance of your photos should guide how you make your exposures. Although it’s a cliche that every situation is different, requiring a tailored exposure for best results, it’s literally true. Finally, how your camera meters and sets its automatic exposure varies more than your might realize.
This might seem complicated, but it’s really not. With a bit of experience and thought, these apparent limitations can become useful tools enabling you to make consistently better photos and save photos that initially seem beyond redemption. The three keys to predictably successful exposure are the typically unused “exposure compensation” feature found on nearly all cameras, using a camera with a wide dynamic range and saving your photo files in an RAW file format wherever possible.
Saving your images in an RAW-plus-JPEG file format is the simplest of the three, and thus the best place to start. Using RAW-plus-JPEG usually requires only a single change to your settings and post-processing of the RAW image in the program of your choice, should you need higher quality than available with out-of-camera JPEG files.
Most better cameras allow you to choose the RAW-plus-JPEG option. You’ll have both a JPEG image for immediate use, if the initial, out-of-camera image is acceptable for your needs, as well as an RAW file should you require a higher-quality result later.
Outdoor photos often require a camera with very high dynamic range for best results. That’s especially true for images made in bright summer sunshine, on brightly lit beaches and snowy hillsides, or when shot “backlit” with the sun or other bright primary light source behind the subject and glaring straight into your lens.
With good dynamic range, you’ll be able to capture good detail in your dark areas without losing detail and texture in the highlights, both important considerations for best-quality final results. Without good dynamic range, either the highlights will go blankly white or the shadows will become inky-black blots more suitable for Rohrshach tests.
Generally, the larger the imaging sensor, the better a camera’s inherent dynamic range. There are exceptions, though. Many of Canon’s midlevel digital SLR cameras have measured dynamic range that’s somewhat lower than the competition, while most Pentax dSLR cameras and Olympus OM-D series compact-system cameras have better measured dynamic range than might be expected from their somewhat smaller APS-C and Micro Four-Thirds sensors.
To effectively use all of the dynamic range of which your camera is capable, you’ll need to save those image files in an RAW format and post-process them on your computer. Why RAW again? RAW formats retain all of the detail captured by your camera. JPEG formats achieve their smaller file size compression by discarding much of the latent detail and color information in deep shadows and bright highlights, retaining only about eight EV worth of data. That’s not enough to bring out the best in your photos made outdoors and in other demanding circumstances.
Most upper-end cameras, particularly mid- to upper-level Nikon, Sony and Pentax dSLRs and Olympus, Fujifilm and Sony mirrorless-system cameras, are capable of retaining 12 to 14 EV worth of data in each RAW file. That’s four to 16 times as much data as a JPEG image made of the same subject.
A much greater range of correction, and possibly salvaging improperly exposed images, is feasible when you have an RAW file’s extra data. Using the wide latitude of Olympus and Pentax RAW files, I’ve been able to make decent prints from photos that seemed hopelessly underexposed at first glance. At http://www.dxomark.com, you’ll find a wealth of objective measured data about the inherent dynamic range of most popular cameras.
RAW image files are larger and are not always readily viewable with the basic software built into Windows and Apple computer operating systems. Windows users can download free Microsoft camera raw codec applications that recognize and properly display RAW images when opening a folder.
Fast RAW Viewer is an even better approach to rapidly sorting through RAW and JPEG files to cull out image files that are obviously duplicative, poorly composed, blurred or badly exposed. The program is available for both Apple OS and Windows computers for a minimal $19.95 license and activation fee. I highly recommend the program. You can download a trial copy or buy a license from http://www.fastrawviewer.com.
Tailoring your exposure to match how your camera actually meters and to achieve a specific end result requires more space than remains this week, so we’ll address that final aspect to crafting an optimum exposure next week.
In the meantime, check out Amazon’s excellent prices for high-capacity, fast USB 3 flash drives. As of Monday evening, Amazon was selling a 256-gigabyte flash drive for a mere $65 with free Prime shipping. A high-capacity, pocketable flash drive like that is an excellent backup device for those bulging photo file directories. It’s also a practical, fast and portable substitute for a mechanical hard drive as your primary image storage.
Local attorney Joe Kashi received degrees from MIT and his law degree from Georgetown University. He has published articles about computer technology, law practice and digital photography in national media since 1990. Many of his articles can be accessed through his website, http://www.kashilaw.com.