How do you focus for bird photography?

I was wondering how bird photographers here, especially those using Nikon gear use the focus points for bird photography.

Do you manually shift the point to cover the bird, simply use the centre point or focus and recompose or some other method. I don't do BIF's as I don't have the strength anymore so only interested in the smaller forest birds.

Thanks for any input. I  shoot with a Nikon D7200 and a 150-600mm lens. 

I am getting good results and I shoot with Back Button focus and manual settings with auto ISO set to 2500 max.

When shooting AF, I like to put my focusing point on the eye of the bird. If the focus point is too large to cover only the eye, make sure the eye is centered in the point. You can shift the point to the eye in your chosen comp, or use the center point, lock focus and recompose as desired. I generally do the former.

Joe

Thanks Joe, that's pretty much what I do to.

Kim
As a general rule, there's never only one way to do anything.  You must find what works for you.  Let's start with how you approach the eye cup.  Some people like to get a larger eye cup to block out all light, and that's certainly an option.  They're not terribly expensive, so you might want to try one.  Which eye do you use to look through the eye piece?  Personally, I use my left eye, cup the right side of the camera with my right hand to block the sun from my right eye, and leave both eyes open.  Squinting with one eye closed for a long period of time can be fatiguing and this really helps.  Also, when you look up from the camera to spot birds, both eyes are already open and you can immediately see.  For small birds you want to use single point continuous autofocus.  It's a fallacy to say you should always put the focus point on the eye.  The real answer is that it depends.  For a prime lens, the depth of field for a given shot is determined by the distance from the camera to the subject and the f-number.  Obviously if the f-number is bigger and the subject is at a farther distance, it will mean a deeper dof, and vice-versa.  If a bird is parallel to the camera, I would say to always put the focus point on the eye.  If the bird is not parallel to the camera, this is where judgment, practice, and knowledge comes into play.  I know that if the depth of field for a given shot is three inches.  That would mean that the center point of that dof is 1 1/2 inches.  Or in other words, for all practical purposes the center point for a given dof distance is half of the total dof.  Now let's say that a bird is not parallel to the camera.  If you focus on the eye, even with a pretty large f number, the tail of the bird will probably not be in focus.  In this case, I suggest focusing on a point of the bird just behind the eye, but close enough to the eye that you don't worry about the eye not being in focus.  By doing this, you increase the chance of getting the whole bird in focus, which I believe is a nicer looking image.  If you need a shot immediately, I would suggest that you focus and recompose the image in camera.  If you get that shot, then you can move the focus points around.  But, since you are not using a prime lens, I suggest that you not worry about focus and recompose.  Just zoom out a bit and that will normally take care of the problem.  Also, by zooming from 500 to lets say 400 will increase your dof slightly.  Today's cameras have enough pixels that's it's not necessary to completely fill the frame.  You said something about forest birds.  Manual with Auto ISO is an excellent mode with good to pretty good light.  If the light is not that good, Auto ISO will meter the shadows and drive up the ISO when it is probably not necessary for a properly exposed image.  In poor light, or if the bird is in good light but there's deep shadows behind the bird, you need to be in full manual so that you're metering the light on the bird, not the entire frame.  Shadows will fool Auto ISO every time and drive up the ISO when it is not necessary.   I rambled, but hope it helps.  Curious how other people might handle achieving proper exposure on the subject.

Gene Gwin wrote:Kim
.........
It's a fallacy to say you should always put the focus point on the eye.  The real answer is that it depends.  For a prime lens, the depth of field for a given shot is determined by the distance from the camera to the subject and the f-number.  Obviously if the f-number is bigger and the subject is at a farther distance, it will mean a deeper dof, and vice-versa.  If a bird is parallel to the camera, I would say to always put the focus point on the eye.  If the bird is not parallel to the camera, this is where judgment, practice, and knowledge comes into play.  I know that if the depth of field for a given shot is three inches.  That would mean that the center point of that dof is 1 1/2 inches.  Or in other words, for all practical purposes the center point for a given dof distance is half of the total dof.  Now let's say that a bird is not parallel to the camera.  If you focus on the eye, even with a pretty large f number, the tail of the bird will probably not be in focus.  In this case, I suggest focusing on a point of the bird just behind the eye, but close enough to the eye that you don't worry about the eye not being in focus.  By doing this, you increase the chance of getting the whole bird in focus, which I believe is a nicer looking image.  ........
......Also, by zooming from 500 to lets say 400 will increase your dof slightly.

Regarding the DOF being centered at the point of focus, that is not true for all circumstances. It changes:

https://www.tonycorbell.com/blog/2015/9/14/depth-of-field-the-13-23-myth


Regarding zooming in and out, that is not true:

https://completedigitalphotography.com/2018/08/focal-length-and-depth-of-field/

Joe

Joe,
I read the article about dof and what It said is that at closer distances dof is essentially half in front and half in back. It's not exactly half and half, but the dof is close enough to half and half that in the field it's a good enough wag. I have read other examples using large telephoto lenses, and their example showed that it is essentially half and half until the subject is farther away and then there's more dof behind the subject. The example they gave talked more about wide angle lenses. It would be interesting to see what a 500mm lens dof of field is at about 20 to 30 feet. I stand by my belief that it is essentially half and half for telephoto lenses at the distance bird photography is done. I base my belief from talking to professionals who know a whole lot more than me and also looking at photos and checking dof. However, in reality, the most important thing is that when taking a photograph that dof is considered and try and adjust accordingly.

The example that the author used when comparing dof regarding zooming does not apply. The example given was taken at two different distances. Let's say at 20 feet you are using a 100mm lens and then you take another photo at 20 feet using a 600mm lens--I think you would agree that the 100mm lens will have a bigger dof. I have to admit that I do not use a zoom lens, and I'm attempting to use common sense here, but it appears evident that at a given distance as the lens becomes larger, the dof becomes less, and vice versa. I certainly do not want to say anything that is not correct. I've looked at lots of charts showing the dof for different size lenses and applied that to zoom lenses. I'm not sure why the lens size vs distance would not apply to zooms? I'd like to see something on this and will look around. I have to say that you're pretty darn good at finding such things. Maybe between us we can make a definite decision regarding zooms. I know that I would like to know for sure.

Thanks for the discussion.

https://www.photopills.com/calculators/dof

I used the dof calculator to determine the total dof for lenses from 200mm to 600mm and the percentage in front and in back of the center point.  For all practical purposes in the field, the dof is essentially half in front and half in back of the center point of the dof.  Also, as the lens size increases, it highlights just how careful you must be with proper focus.  Based on these numbers, I have to assume that if you zoom from 500mm to 400mm that it would increase the depth of field by 1.68 inches. 

These numbers are based on a distance of 25 feet to the subject and an aperture of f/5.6.

Lens size          DOF Total          DOF in front         DOF behind        

200                    18.96"               48.43%               51.57%

300                      8.28 "              49.32%               50.69%

400                      4.56"               49.62%               50.38%

500                      2.88"               49.67%               50.24%

600                      2.04"               49.83%               50.17%
 

Kim, here is what I do, most of the time, with my Nikon 500mm lens and my D500.

Auto ISO in Aperture priority mode with minimum shutter speed usually set to 1/1000 or faster. I do not limit the max ISO that much as noise is of secondary interest. Custom settings a1 and a2 both set to Release.

F stop is set to F 4 or widest opening. Sometimes I set a smaller opening to allow for more depth of field. And sometimes I will focus on a spot just before the eye to get the eye and beak in focus when close to the subject.

Back Button Focusing (AF-ON) . Matrix Metering or Center weighted meter or Highlight weighted metering depending on lighting conditions. Exposure compensation as needed.

AF-C set to S or Dynamic setting. S if the bird is stationary; Dynamic, D 25 if it is moving; Group area AF if bird if flying towards me.

I usually leave the focus point in the center position, focus and recompose. If birds are moving, just use the center point with a Dynamic setting. If time and subject allows for moving the focus point I will usually move it.

If time allows, for stationary shots, I take a few frames after tweaking the focus manually. And sometimes I use Live View. And I might turn off Auto ISO and use a lower shutter speed and lower ISO. I switch Auto ISO off and on by pressing the ISO button on the camera and turning the main command dial.

Joe

Thank you gentlmen for the extended replies.

Although my lens is a zoom 99% of my shots are at 600mm @ f8 for birds. I had the lens maximized for sharpnes by the manufacturer at 600mm. I handhold all my shots from a seated position with vibration control on, consequently I limit the shutter speed to 1/500s.

I do use the centre point and refocus as nessecery if needed.

Joe Smith, I use the settings you outlined as available on my D7200. Thanks for your imput.

I'm going to chime in because some of the advice given for other camera models will not yield great results on a D7200.  The D500 has a MUCH faster and significantly advanced AF system.  If you put the D7200 into the same modes it simply will not keep up.  The image processor, which doubles as the AF processor, in that camera isn't fast enough to do the computations and keep the AF system accurate on a fast moving subject if more than 9 AF points are active.  While I totally agree about the D500 settings above, they will leave you wondering what's wrong with your camera on a D7200.  By far the most success you will have with a D7200 is if you put the AF system in AF-C, make sure the camera is set to release priority and then use d9 as the AF point.  This method achieves AF on the selected AF point and then hands off to it's 9 nearest neighbors if you fall off of the point that you autofocused on.  Since the 9 imediate neighbors don't take up a lot of real estate, your technique will ahve to be honed in order to keep the subject in that area.  Furthermore, you will want the selected AF point to be one of the ones near the center as you only have cross type sensors in that area.  On something very predictable, a bird that soars for example, you might be able to get away with d21 but the motion must be very predictable.

The D7200 is a capable camera for in flight birds but it simply does not have the internal computing power of the more advanced cameras to use the settings that make this type of photography easier on something that is moving in a complex manner.

Hope that helps.

P.S. I own both the D500 and D7200