We all remember from English class the rule of Subject -- Verb Agreement, which means you wouldn't say "That book are great?" but rather "That book is great." The same rule can be applied to photography, if we look at how the subject of the photo relates to the framing of the picture, what I call Subject -- Frame Agreement. The most common incident where we find this error is in distance. Being too far away from the subject ...
To get better photos when at the zoo bring a zoom lens and a circular polarizing filter. With the zoom lens you can get a close up of the animal even if they are in the back of their enclosure. The circular polarizing lens will let you shoot through glass without worrying about a reflection.
