• Flash? Check the zoo's rules and its list of exhibits. Common sense tells you it's not a good idea (and likely prohibited) to use flash in nocturnal animal exhibits or habitats. The idea is never to disturb or upset the animals.

• It's usually not the animals, but the exhibit that will make flash difficult. If there's glass, it's a problem. With a compact camera or a D-SLR's built-in flash I'd suggest you turn off the flash and boost the ISO. If flash is the only way to get an acceptable exposure, try standing at a 45-degree angle to the glass...and then vary that angle and check your results. You'll get the best results with a Nikon Speedlight on your camera; you can tilt the flash head up to vary the angle, or you can bounce the light off the white card that comes with every Speedlight. Shoot a bit, check the LCD, see if you need to change your position or the flash's angle. Glass without flash? Shoot at an angle and watch for reflections, which can be a problem even without flash. Often you can get close to the glass, and if you're careful, practically eliminate it from the picture (I took the photos of the Gelada baboon and the Siberian tiger through glass). In any case, obey regulations. Don't bang on the glass—in fact, don't try to get an animal's attention, glass or not, in any noisy or disturbing way. An upset animal doesn't make for a good photograph.

• A D-SLR is going to give you lens interchangeability, the most flexibility and the option of total automatic operation. I shoot mostly with a D3, sometimes with a D90 or a D60. I also shoot with a COOLPIX P90, which gives me 12.1 megapixels, a wide-ranging zoom, image stabilization and the option of manual settings. I often set it for Program operation, then use exposure compensation or change the ISO when I need to. When I want a blurred background, I set the P90 for aperture priority and choose an aperture in the f/2.8 to f/5.6 range. It's a lot of camera, and I don't ever underestimate the quality of a compact's images: I started my career with a COOLPIX and was able to do amazing things—I even got a cover photo of an annual report with it.

• Research your zoo. You'll want to know about photo ops that'll bring you eye to eye with the animals. A current bird show at the Bronx Zoo will allow visitors, and their cameras, to get 12 inches from animals perched on a handler's glove.

• Timing is everything, especially when it comes to light. Try not to shoot on very bright sunny days; overcast days are the best for photographing at the zoo, and so are "off weather" days because many animals thrive when it's snowy or rainy, even if people don't. And an off weather day will mean fewer people (avoiding crowds is always a good tip for zoo photography, so think early morning or late afternoon). If it's snowing, think of the animals that enjoy that weather—snow leopards, polar bears, tigers, snowy owls.

• Realize that you may not get the best shots your first time at the zoo. First-timers should be exploring, learning where things are, figuring out what they prefer to see and shoot. I suggest doing a recon before you bring all the gear. The more you know about your zoo and the more familiar you are with it, the better you can plan your shoot. Buying a membership is a good idea because it allows access over and over again. Members won't need to do the whole zoo in one day; they can pick a section and work it, then come back and do the same for another section.

• Take advantage of the zoo's website. You can see maps of the layout, find out about special events and educational programs and check on the rules and regulations for photography. And one more important thing: find out about the animals' feeding times. Animals know when it's feeding time, and that's when they're going to be their most attentive. Sea lions come to attention; other animals wake up and come around the feeding areas. Feeding time is animal activity time.

• When you're taking photos at an exhibit, take a photo of the signage as the first or last image. The signs usually have information on the animals, maybe a conservation tip. Later you'll be able to identify what you've photographed for captions or just for your own information. It'll help you organize your shots and you'll be learning about the animals and their environment so you can talk about them. We can all learn something; I went out a few weeks ago and found out that September 5th was International Vulture Awareness Day. Who knew?

• My four-P key to zoo photography: make a plan; have patience and wait for the right moment; practice at home with your pets and the nature in your backyard; embrace your passion for photography.

Well, that's our zoo story. We trust you'll be ready when International Vulture Awareness Day rolls around again.

Julie Larsen Maher has been an NPS member since 2008.