Tracy,

Your image looks as if the camera has been set to use multiple focusing points within the scene. In your viewfinder you should see several tiny, transparent, squares; these are the available focusing points. If you camera is set for multiple points when focus is achieved the squares should flash red.

Check your camera manual and the focus capture mode and make sure is is set for "Center Spot" focus. You will then be able to place the center square in the central subjects eye and lock focus for the image. Focus lock is made by pressing the shutter button half way down. Full press captures the image and the exposure.

Once you capture an image with your selected focus point you can then study Depth of Field (DOF).

Michael G

Hi, Tracy ! I hope that you are having a great day..

Assuming that digital photography with a DSLR camera is new to you, I will go ahead and ask you if you had your camera's focusing mode set whereas it was focusing upon a small area in the center of its viewfinder ?

If your camera was set to focus upon a small area in the center of its viewfinder, once that you had focused upon, let's say, the lady's face, did you remember to continue holding the shutter release button half way down so that when you had recomposed the overall image and, actually, had tripped the shutter, the original focus point would have remained to be the same ? If you had done this, then, I would have to say that, perhaps, you should have your lens tested for autofocus accuracy by a qualified technician whereby he or she can recalibrate your lens so that it will autofocus to its full ability.

Tracy, also, remaining to assume that you are new to DSLR photography, if you have a chance to reshoot the same scene with the same subjects at hand, you might want to have the boy move his legs and feet inward so that there won't be so much empty space on the right side of the photograph.. Best said, empty space in the scene has nothing to offer.. Anyway, either do that, or you may want to move slightly to the right so that you will get a shot at a different angle.. Doing such will enable you to tightly crop the scene in your camera's viewfinder whereby it will offer better results for your horizontal formatting..

My apology to you if my critiquing your photograph was not wanted, however; if you are new to the art, please know that my intent was to only help you to present your best in the future.. Also, please know that you have shown us a splendid job as is and, personally, I look forward to seeing more photos from you soon. ;-)

My Best Regards for you, Tracy, & keep up the good work !
~ Doug ~

Tracy,

There are way too many variables involved to provide you with a good answer.
Example: Lens focal length, distance between subjects and camera, separation between subjects, and camera make and model.

Check out the link below and try some variables.
http://www.dofmaster.com/dofjs.html

If all the subjects will be sitting "cheek to cheek" you will not have to worry much about the angle off set from center focus. (If your distance from camera film plain to center subject is 20 feet and the outside subjects are 5 feet apart the angle offset will cause an error in your DOF calculations. The two outer subjects will be slightly farther away from the camera than the center subject).

Using multiple focus points is not a good idea, the camera will try to average all the focus points and provide an out of focus image. If you have three subjects and all are sitting 3 feet apart the camera will focus on the center point, two of the outer subjects, and all of the background. It will become a wild guess on the cameras' part to which focus point is used for image capture.
Your best bet is to use Center Spot Focus and set focus lock on the subject in the center.

Keep in mind that along with DOF you also have HFR (Hyper Focal Range) to help you get all subjects in sharp focus and allow the background to fade into soft focus.

At any Aperture value you will have a set DOF, within that DOF you will have a set number of feet behind the subject in acceptable focus and a set number of feet in front of the subject. A general rule says 1/3 in front, and 2/3 behind the subject.
HFR allows you to set the focus on the central subject (on the eyes) and switch to manual focus and adjust the focus ring to bring the soft focused background to just behind the head of the central subject, it also allows you to keep all of the outer subjects in sharp focus while paying attention to the background for all the subjects.

This is artistic control over the capture and can be used in reverse to adjust the foreground where required.

Michael G