family group photo issue

[junqi]

Dear all,

i am capturing my family using f2.8 but some of my family member tend to blur out.

is it i open aperture too wide which cause shallow of depth?

the solution is it to increase the aperture instead?

anyone kindly advise me thank you.

 

[soufiej]

Yes, smaller aperture (larger f-stop value) will increase DOF As will the distance between your lens and the subjects. and the focal length of your lens.

A Flexible Depth of Field Calculator

 

[Designer]

is it i open aperture too wide which cause shallow of depth?.

Yes

the solution is it to increase the aperture instead?

Using the correct terminology, you would actually make the aperture SMALLER, denoted by the larger denominator such as: f/16 or f/22 for instance.

Also, when photographing people, be sure the shutter speed remains at a fairly fast (quick) shutter to stop motion blur.

 

[junqi]

is it i open aperture too wide which cause shallow of depth?.

Yes

the solution is it to increase the aperture instead?

Using the correct terminology, you would actually make the aperture SMALLER, denoted by the larger denominator such as: f/16 or f/22 for instance.

Also, when photographing people, be sure the shutter speed remains at a fairly fast (quick) shutter to stop motion blur.

Hi designer,

i have try put my mom on left side and father on right side. but when i focus using single af point my father get blur out. do i have to change the focusing mode like area focus or 16 af point focus ? or i have to use a smaller aperture instead? but i did saw other people work where they actually put their mother left side and father right side both seems to be in focus. Furthermore they are using aperture f2.8. anyone can advise me ? for taking a single target i have no issue with it. but more than 1 person the 2nd person always tend to blur out.

 

[ronlane]

The depth of field at f/2.8 is so shallow, that the subjects have to be in the same plane to get them in focus.

Check out the DOF calculator that @soufiej linked in post #2. This will help you understand how much room you need and have for sharp focus at certain distances.

Edit: Example if you have a crop sensor (1.6x) with a 70-200mm f/2.8, at f/2.8, 15 feet from your subject(s), you have .75 feet (9.02 inches) of area that will be in focus.

Hope that helps.

 

[Designer]

i have try put my mom on left side and father on right side. but when i focus using single af point my father get blur out. do i have to change the focusing mode like area focus or 16 af point focus ? or i have to use a smaller aperture instead? but i did saw other people work where they actually put their mother left side and father right side both seems to be in focus. Furthermore they are using aperture f2.8. anyone can advise me ? for taking a single target i have no issue with it. but more than 1 person the 2nd person always tend to blur out.

As ronlane has written, the DOF is is only 9 inches total.

So to get both people in reasonable focus, their faces have to be the same distance from the camera.

If each of their noses are 8 feet from the camera, then their ears will be about 8 feet, 6 inches from the camera and therefore should be in focus. If you measure the distance to each person, and they are both exactly the same distance from the camera, then you should need only one focus point. Focus on one person's eyes and if the other person's eyes are the same distance, then both people will be in focus.

Even with 16-point AF, the camera will select only one of those points to be in focus, not all 16.

My recommendation is to use a smaller aperture than f/2.8 so you will not have to get everyone the same distance from the camera.

 

[Derrel]

Yes, for small-group photos ushc as three to five people in closely-space, tight groups, the middle apertures of f/5.6 to f/8 are very useful. For larger groups, f/11 or thereabouts might be required to get everybody in good sharp focus.
Moving the camera back, and farther from the group, increases the amount of depth of field fairly rapidly. If the camera is fairly close, focusing becomes VERY critical, and at times, very tricky.

 

[junqi]

Yes, for small-group photos ushc as three to five people in closely-space, tight groups, the middle apertures of f/5.6 to f/8 are very useful. For larger groups, f/11 or thereabouts might be required to get everybody in good sharp focus.
Moving the camera back, and farther from the group, increases the amount of depth of field fairly rapidly. If the camera is fairly close, focusing becomes VERY critical, and at times, very tricky.

thanks. if my camera is very close how to focus on 3subject in focus ? i can see some of them using 2.8 and all subject are in focus without any issue. i understand that the longer the focal length the lesser depth of field and the shorter the focal length the more depth of field it is. i was wondering how people can do it focus on 2 or 3 subject using a wider aperture. are you able to advise me on this?

 

[Derrel]

Three people , two in front, one in the back but leaned CLOSE to the two in front, requires about a two foot deep depth of field band, at minimum. Less can work, but two feet is what I think of as the minimum.

FORGET shooting ANY group photos at f/2.8 unless the distance is 20 feet or more. And even then, f/2.8 is a bad choice.

Bokeh simulator depth of field calculator THIS one shows a bokeh simulation, and DOF. This second site is the "classic" on-line DOF calculator Bokeh simulator depth of field calculator

The degree of background blurring not a constant, linear progression, and the results vary, based on focusing distance; distance to the background located BEHIND the focused distance, lens f/stop; and the size of the people in the frame. Frankly, f/6.3 can give a nice, defocused background if the people are close, like 10 feet, but the background is very far behind them, and the lens is a short telephoto model.