|Snow, ice and a cold stream are all rendered with detail as evidenced by the histogram where there's a slight gap between the right edge and the data graph. Any data touching the right edge has no detail.|
Antarctica And Other Snowy Venues
Q What setting would you recommend to shoot in Antarctica? Should I set my camera to program or aperture priority? What ISO and white balance should I use? Do I need to use a polarizer or neutral-density filter?
A Winter is upon us, and whether you're in Antarctica, Yellowstone or any other place with snow, it's important to recognize that vast areas of bright, reflective white pose predictable exposure issues. Your camera's automatic metering and exposure settings will attempt to neutralize the brightness, giving you gray snow and ice when what you really want is white with detail. Here's where histograms come to your aid.
Take one image with the camera set to aperture priority. Look at the histogram for the image that displays on the LCD screen on the back of the camera. If there's image data stacked up against the right edge of the histogram, there's no detail in the whites within the image. If the image data is registering toward the middle, your snow is gray. Adjust the exposure manually until the "snow" data in the histogram is close to the right edge, but not touching it. Lock this exposure in and continue to check it as the light changes.
Today's DSLRs offer expanded ISO settings that are extremely useful when photographing in low-light situations or to speed up action capture. The trade-off for fast capture is noise, similar to grain, which is especially noticeable in broad swaths of uniform color, such as the sky or a snowfield. Usually when working around snow and ice in the daytime, there's plenty of light, so the ISO can be set to the optimum number for your camera, typically around 100; if you want to increase your shutter speed and/or depth of field, you can increase the ISO a notch or two to 200 or 400. I'd use a RAW capture mode so that white balance can be set later at the computer, but if you were to set a generic white balance, it would usually be daylight. A lot of blue tones will come off the ice and in the snowy shadows, so auto white balance isn't a good idea.
Polarizers can give a rich look by darkening the sky and minimizing reflections off the shiny surfaces. You'll need a neutral-density filter to slow down your exposure if you're going to photograph moving water amidst your snowfall. A new consideration for shooting video with your DSLR is that you'll want a shutter speed that runs around 1⁄60 sec. for a natural look. A neutral-density filter will help you to achieve that speed in the overbright conditions of Antarctica.
Q How can I keep my image files from losing their quality? Does opening a file in Photoshop too often make it worse? I printed an image that was taken just two years ago, and the pixels in the sky were showing! How can I prevent that from happening to my other images?
A The passage of time doesn't degrade an image file. But JPEG files lose data every time they're opened and resaved; the file actually becomes smaller. You can avoid this problem by storing your files in TIFF and Photoshop (PSD) formats because these can be opened, closed and saved as often as needed without any loss of quality.
This offers me a good opportunity to remind everyone about proper file storage. You can lose your images forever with hard-drive failure, so always back up your files to portable drives and keep a set of these away from your computer, in a bank vault or a friend's home. If you have a lot of images backed up on CDs or DVDs, it's time to take a good look at them and transfer them to more reliable media.
There can be many reasons for the pixelation of the sky in an image. If yours isn't a JPEG file that has been opened and resaved numerous times, the pixelation may have been there from the beginning. If you shot the file as a JPEG (8-bit), banding may appear in the sky due to lack of sufficient information—that is, poor image quality. Shooting in RAW mode (16-bit) captures much more image data for smoother gradations. Noise from expanded ISO captures is also more evident in the sky than in more detailed areas, and this presents itself as a multitude of red, blue and green pixels. Finally, be careful about how you're processing your images in Photoshop. Areas of consistent tone can appear to be pixelated due to oversharpening of the image. This might work for the foreground detail, but has the effect of sharpening individual pixels in an area such as the sky.
Taking The Long Road
Q I'm thinking about getting my first supertele lens. You've said in the past that your supertele lens of choice is the Canon 500mm, not the 600mm, due to the extra weight of the 600mm. Now that the new Canon 600mm weighs closer to the old 500mm, would you still suggest getting the 500mm instead of the 600mm (cost factor aside)? With your 500mm, do you often need to use a 2x tele-extender to get enough reach? The lens will be used for large birds and animals on safari and small birds later.
A Supertelephoto lenses are a big commitment both in cost and technique, but they open new worlds of possibility to photographers of birds and other wildlife. The 500mm is still my first choice for these subjects, and I've taken it on a number of African safaris. You'll find that there's never enough "reach" when photographing elusive wildlife, especially small birds. I always carry 2x and 1.4x tele-extenders with me, as well as an extension tube to facilitate closer focus. I have on some occasions actually stacked both the 2x and the 1.4x tele-extenders, offering a 1400mm telephoto with a maximum aperture of ƒ/11. Due to the advanced capabilities of today's DSLRs, a higher ISO can be used, making ƒ/11 a manageable ƒ-stop with a reasonable shutter speed.
The new 500mm Mk II and 600mm Mk II telephotos from Canon are smaller, lighter and purportedly sharper than their predecessors. Unfortunately, they're also considerably more expensive. Given the choice of the new supertelephotos, I would still go with the 500mm. Smaller and more versatile still trump a larger lens when traveling and occasionally handholding the lens in the field. I often photograph from kayaks and while stalking small birds, in which cases, using a tripod isn't possible. Still, every movement is magnified with a supertelephoto, so be sure to invest in a sturdy tripod and a robust ballhead for your long lens, and use it faithfully whenever conditions allow.
Q I've been asked to give an image program at our camera club. What presentation program do you use for your programs? I'm working with a Windows laptop.
Los Angeles, California
A All the programs I give on my Mac around the country are presented using Microsoft PowerPoint. A program for Windows that's less expensive and has many great features is ProShow Gold from Photodex. It's at version 4.52 with a cost of $69.95. You can incorporate videos and music, as well as many cool animations to add interest to your show.
Within my main PowerPoint presentation, I typically insert additional programs for variety using Animoto for Windows or Mac and Boinx FotoMagico 3 for Mac. Animoto is a very powerful program: You upload a number of images and music to Animoto's website, and a computer mixes it with stunning animations not normally available to us mere mortal photographers. The program was developed for wedding photographers to market to their clients. I find it works great for outdoor subjects, as well. A free trial version will give you an idea of what it can do. The Plus version is $30 a year; the Pro version runs $249 for unlimited use for 12 months. It's not cheap, but it does amazing things.
Photos On The Level
Q I want to level my tripod for both panoramas and video pans, but there isn't a bubble level on the tripod base. Any suggestions on accomplishing this without buying an expensive new tripod?
A There's an accessory out there from Really Right Stuff (RRS) that should work for you. RRS offers two sizes of Tripod Leveling Plates equipped with a spirit level ($45). You place the plate between the tripod column base and the head, and use the spirit level to help you position the tripod legs accurately.
While this accessory works great for leveling your tripod, you still need to level the camera with a simple two-axis bubble level that fits into the camera's hot-shoe. The combination will let you pan for a series of panorama shots or video with a horizon that's consistent from one end to the other.
For information about upcoming seminars and digital-imaging workshops, visit www.georgelepp.com. If you have any tips or questions, address them to: OUTDOOR PHOTOGRAPHER, Dept. TT, George Lepp, 12121 Wilshire Blvd., Suite 1200, Los Angeles, CA 90025-1176 or online at www.georgelepp.com.