Like most other genres of photography, bird photography is very detail-oriented. If you can learn to look out for a few specifics while out photographing and while culling through your images, you can really take your work up a notch.
Of course, what makes a good photograph is up to each individual viewer and there are no hard-and-fast rules. However, I think that by being mindful of the following points, you will see big improvements in your bird photographs...
1. Light Angle
Considering the angle of light in relation to your subject is hugely important in bird photography. It will not only determine the appearance of the resulting images, it will also determine how you go about approaching the bird and how you expose your image. There is no one light angle that looks best, though if your goal is to produce vibrant, detail-rich images, generally speaking, approaching with the light at your back is the answer. This is especially important when shooting in direct sunlight. When the light is more diffuse, it's not necessary to be as fastidious.
Keep an eye on your shadow as you approach, try to keep it pointed towards the subject.
2. Head Angle
Failure to wait for the "right" head angle is one of the most common mistakes made by amateur bird and wildlife photographers.
Different types of birds will look better while giving certain head angles, so there isn't always one ideal rule to follow. The eyes of most birds are positioned on either side of their head, making it challenging to include both in a pleasing way. The rule of thumb is waiting for the head to turn slightly towards the camera from perpendicular. This will give a nice profile view of the bill, while having enough eye-contact to really connect with the viewer. A 90 degree angle or having the bird looking slightly away from the camera typically does not render a pleasing shot, with a disconnect happening between the camera and subject.
On the contrary, birds such as Owls and Eagles for example, can look fantastic head on. Their front-facing eyes are accentuated and lock in with the viewer.
You'll soon find that far less photos need to be deleted as a result of waiting for the right angle.
This ties in with tip numbers 1 and 2, as oftentimes, a good light angle and head angle correlate with a good catchlight.
What is a catchlight? Simply put, it's the reflection of the light source in the eye of your subject.
Why is having a catchlight so important? Birds without catchlights in their eyes can often appear lifeless in photos. This applies especially to birds with dark irises as catchlights are rarely obvious in the eyes of those with light irises.
Direct sunlight causes a bright, sharply-defined catchlight, whereas more diffuse, cloudy light results in a muted catchlight - both can be very pleasing. Extra care must be given to achieve a desirable result on sunny days, as the light angle is very precise, as will be the corresponding reflection.
By taking lots of frames and watching carefully, you'll stand a good chance of catching that perfect twinkle in the eye.
If only we could press pause, walk out and neatly arrange the feathers and posture of our subjects, we would all have memory cards full of perfect images. Instead what is required is attention to detail and the patience to wait for that ideal moment. A great pose should say something about the bird or display its best attribute - perhaps even its namesake feature.
A Fiery-throated Hummingbird presents its dazzling iridescence.
I've photographed Hoatzins on many occasions in South America, but I've found this to be the only shot of mine that exemplifies their character. Waiting for it to raise its wings and foot as it strut along this fallen tree made all the difference.
5. Look Past The Bird
It's not uncommon to see photographs of birds posed perfectly in great light, only to be let down by a terrible background.
Learning to look past your subject is one of the most important skills you can develop as a nature photographer. Determining if other elements in the scene are beneficial or detrimental, is the first step. The next step is making as plan as how to best include them in your frame or avoid them altogether.
Lining the bird up with a distant, even-toned background will often yield the best results. This allows your subject to pop out from its surroundings so the background will not compete for the viewer's attention. If your background is further away from your subject than you are to it, there's a good chance it will be rendered smoothly in your photograph - especially if you're using a telephoto lens and a large aperture.
In essence, these two images of a Greater Yellowlegs are the same; the only major difference is the background. The first shot features a good head angle, a good light angle and a nice catch light, though it is let down considerably by a terrible background.
The Problem: The background in photo number 1 is way too close to the subject. Instead of being attracted to the bird, the viewer's eyes are dragged to the heavy contrast and distracting bits of vegetation that surround it.
The Solution: Waiting for the bird to move to a more open area where the background is far more distant, allowing it to pop and look more three-dimensional.
As you approach, be aware of what is behind the bird. Is there an obtrusive branch cutting through the scene? Are there bright patches of sky scattered throughout the foliage in the background? Is there a beautiful, flowering shrub beyond the subject that could add a nice pop of colour? More often than not, one or two steps in a given direction is the difference between an okay photo and a great photo.
If you think you have the shot, scrutinize your image. It's almost guaranteed that by tweaking your position, or waiting for your subject to move into the right spot, it can be improved upon.