Need guidance: Multiple subjects in the same focus plane

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GamzeQ

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Hello everyone,

I need help/guidance on focusing on multiple subjects, specifically birds when they are on the same focal plane: both birds are on the same focal point vertically or horizontally and I want to capture both of them sharp. I'm having difficulty as Auto Focus keeps the tab on the only one. I understand the increasing the DoF but my challenge is when they are next to each other.

Should I turn off subject detection off and use Wide L? Can use some help. Thank you in advance.

Camera: Nikon z9. Example image attached. The one on the right is in focus, and the one on the left is slightly out of focus.
 

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Hello...
I'm a bit confused... If the birds are on the same plane, then focusing on one bird should result in accurate focus on the other bird(s)... see example.
Typically, but not always, you are best having critical focus on the bird in the foreground and letting depth of field capture the focus of birds that are slightly behind. If the birds are not close to the same plane, then you can produce pleasing pictures by focusing only on the nearest bird, opening up your aperture, and render the rear birds soft and rely on bokeh to create separation. Alternatively, you can focus-stack... take a picture of your nearest bird and then take another picture of the bird that is farther back. You then can use photoshop or other software to combine the images.
As for AF mode... this often depends on camera type. Your description leads me to believe that you are using Nikon. There is not "magic" AF mode that will get two birds that are not aligned in focus... unless you are using focus bracketing.

Maybe I helped,.. but I fear I made things worse. In the images pictured, I focused on the nearest bird using Spot AF and relied on depth of field to capture the focus of the other chicks.
regards,
bruce
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Think of the plane of sharp focus as emanating parallel to the sensor over the entire field of view at the one focus distance. That is the goal of the lens designer at least. Many lenses have oddball curvature of field but you can't really predict that.

So if the camera is tilted up or down or rotated left or right the plane will follow it but still parallel to the sensor.
 
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BLev65 said:
Hello...
I'm a bit confused... If the birds are on the same plane, then focusing on one bird should result in accurate focus on the other bird(s)... see example.
Typically, but not always, you are best having critical focus on the bird in the foreground and letting depth of field capture the focus of birds that are slightly behind. If the birds are not close to the same plane, then you can produce pleasing pictures by focusing only on the nearest bird, opening up your aperture, and render the rear birds soft and rely on bokeh to create separation. Alternatively, you can focus-stack... take a picture of your nearest bird and then take another picture of the bird that is farther back. You then can use photoshop or other software to combine the images.
As for AF mode... this often depends on camera type. Your description leads me to believe that you are using Nikon. There is not "magic" AF mode that will get two birds that are not aligned in focus... unless you are using focus bracketing.

Maybe I helped,.. but I fear I made things worse. In the images pictured, I focused on the nearest bird using Spot AF and relied on depth of field to capture the focus of the other chicks.
regards,
bruce
View attachment 100186
View attachment 100187
Click to expand...
Thank you for the pictures and explanation. Here is my example: The one on the right where the focus is latched on and the one on the left is slightly out of focus. But I was using the Wide Small. As to camera, Nikon z9.
 
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GamzeQ said:
Thank you for the pictures and explanation. Here is my example: The one on the right where the focus is latched on and the one on the left is slightly out of focus. But I was using the Wide Small. As to camera, Nikon z9.
Click to expand...

What focus area was used does not really matter as far as the plane of sharp focus is concerned. Using wide small doesnt mean everythng within the wide small is in focus. The af drives the focusing motor to a certain distance and that distance parallel to the sensor is the plane of sharp focus.
 
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GamzeQ said:
Thank you for the pictures and explanation. Here is my example: The one on the right where the focus is latched on and the one on the left is slightly out of focus. But I was using the Wide Small. As to camera, Nikon z9.
Click to expand...
For the image you shared, I would use either small wide or large wide with "Bird Detect." The bird detect software will generally pick the closest eye (the bird on the left). Depending on your lens and your camera to subject distance, I'd stop down to f/8 to f/11. By doing this, you will have good enough detail in the eye of the bird on the right. Finally, your sharpening routine can be used to match the level of detail and sharpness to the bird in the foreground. Doing this should make it appear that both birds are equally sharp.

regards,
Bruce
 
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Previous discussion and Advice

How to get multiple subjects in focus AND maintain image quality?

Below is example photo from my trip to the park yesterday. Thi8s photo is a composite, because I simply could not get both ducks in focus. I was at the time shooting with a 500pf and went up to f11 to try to broaden the depth of field enough to make this work, but it wouldn't - there was just...
bcgforums.com bcgforums.com


DOF overview, backgrounds

 
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As others have mentioned, if the subjects are in the same plane of focus, even if you just focus on the eye of one bird/ animal, all of them will be sharp. If they are not sharp, it simply means all the subjects are not in the plane of focus. If they are slightly in the front/ back, you can adjust the DOF and see if it works. Another option is to keep the aperture the same but slightly adjust your angle, say from eye level to slightly above. For cooperative subjects, you can also try focus stacking, i.e. focus on subject 1 first, take a shot and then focus on subject 2, take a shot and then blend the 2 images in post.
 
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GamzeQ said:
Hello everyone,

I need help/guidance on focusing on multiple subjects, specifically birds when they are on the same focal plane: both birds are on the same focal point vertically or horizontally and I want to capture both of them sharp. I'm having difficulty as Auto Focus keeps the tab on the only one. I understand the increasing the DoF but my challenge is when they are next to each other.

Should I turn off subject detection off and use Wide L? Can use some help. Thank you in advance.

Camera: Nikon z9. Example image attached. The one on the right is in focus, and the one on the left is slightly out of focus.
Click to expand...
Cameron is right…use more DoF and it SD or not will make no difference. And watch those videos from that guy named Steve…he’s a pretty sharp cookie I hear😀😀.
 
GamzeQ said:
Hello everyone,

I need help/guidance on focusing on multiple subjects, specifically birds when they are on the same focal plane: both birds are on the same focal point vertically or horizontally and I want to capture both of them sharp. I'm having difficulty as Auto Focus keeps the tab on the only one. I understand the increasing the DoF but my challenge is when they are next to each other.

Should I turn off subject detection off and use Wide L? Can use some help. Thank you in advance.

Camera: Nikon z9. Example image attached. The one on the right is in focus, and the one on the left is slightly out of focus.
Click to expand...

Looking again at the example you posted, it seems you are positioned a bit to the left relative to the position where both birds would have fallen in the same plane. I know it sounds a bit simplistic, but it works if one imagines a giant flat window always parallel to the sensor. The window can get nearer or farther from the sensor as you focus but only the parts of the subjects that touch the window at the same time are in focus at the same time. Parts in front of or behind the window might be 'acceptably sharp' due to depth of field, but that is not the same thing.
 
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BLev65 said:
For the image you shared, I would use either small wide or large wide with "Bird Detect." The bird detect software will generally pick the closest eye (the bird on the left). Depending on your lens and your camera to subject distance, I'd stop down to f/8 to f/11. By doing this, you will have good enough detail in the eye of the bird on the right. Finally, your sharpening routine can be used to match the level of detail and sharpness to the bird in the foreground. Doing this should make it appear that both birds are equally sharp.

regards,
Bruce
Click to expand...
Thank you for your reply however, using f/8 and higher also gets other birds around them which was a pretty crowded group, in focus as well and I was trying to prevent that. I used f4.5 which now I'm learning was too much. I will change it. Thank you again
 
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GamzeQ said:
Thank you for your reply however, using f/8 and higher also gets other birds around them which was a pretty crowded group, in focus as well and I was trying to prevent that. I used f4.5 which now I'm learning was too much. I will change it. Thank you again
Click to expand...
Photography is often about compromises. If your goal is to take a shot with minimal post processing, you'll want to position yourself with minimal distractions so as to isolate your subject from the other birds. Alternatively, you can look to compose your image to encompass many birds in the frame. Looking again at the shot you shared, there is a bird in the foreground and stopping down will increase the degree to which it distracts from your main subject. Maybe shifting to the right might help creating some separation. Alternatively, you can think about how you can eliminate your distracting elements by using some of the Ai remove tools in photoshop... There once was a camera called the "Light Field Camera" that took an image in multiple planes and then you could decide your point of focus in post.. this camera was not very popular and does not do well the photo market ( https://www.adorama.com/us1846608.h...wcB&gclsrc=aw.ds&utm_source=inc-google-shop-p ).

cheers,
bruce
 
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fcotterill said:
Previous discussion and Advice

How to get multiple subjects in focus AND maintain image quality?

Below is example photo from my trip to the park yesterday. Thi8s photo is a composite, because I simply could not get both ducks in focus. I was at the time shooting with a 500pf and went up to f11 to try to broaden the depth of field enough to make this work, but it wouldn't - there was just...
bcgforums.com bcgforums.com


DOF overview, backgrounds

Click to expand...
Very helpful and thank you very much!
 
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thelordofthelight said:
As others have mentioned, if the subjects are in the same plane of focus, even if you just focus on the eye of one bird/ animal, all of them will be sharp. If they are not sharp, it simply means all the subjects are not in the plane of focus. If they are slightly in the front/ back, you can adjust the DOF and see if it works. Another option is to keep the aperture the same but slightly adjust your angle, say from eye level to slightly above. For cooperative subjects, you can also try focus stacking, i.e. focus on subject 1 first, take a shot and then focus on subject 2, take a shot and then blend the 2 images in post.
Click to expand...
Thank you for reply and information. In that case, I couldn't do focus stacking as there were many flying in and out of the area and they were constantly moving due to their mating season. I did what I could under these circumstances. Increasing the focus would have helped for sure. Thanks again.
 
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GamzeQ said:
Hello everyone,

I need help/guidance on focusing on multiple subjects, specifically birds when they are on the same focal plane: both birds are on the same focal point vertically or horizontally and I want to capture both of them sharp. I'm having difficulty as Auto Focus keeps the tab on the only one. I understand the increasing the DoF but my challenge is when they are next to each other.

Should I turn off subject detection off and use Wide L? Can use some help. Thank you in advance.

Camera: Nikon z9. Example image attached. The one on the right is in focus, and the one on the left is slightly out of focus.
Click to expand...
You can also focus manually which I prefer when the situation does not really require auto focusing. You do want to position the camera so it is equidistant from the subjects. This is more often a consideration with macro photography but it applies to your situation as well.

Choice of focal length is also a factor in terms of the DOF and getting closer so you can use a shorter lens or zoom setting will help.
 
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i do think it would be cool if they had a mode that would pick the subjects in an af box, compute the distance to both, then set focus to between them, then do the dof calc and decrease the aperture to cover both subjects if possible :LOL:

[corrected]
 
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John Navitsky said:
I do think it would be cool if they had a mode that would pick the subjects in an af box, compute the distance to both, then set focus to between them, then do the dof calc and increase the aperture to cover both subjects if possible.
Click to expand...
Actually, they would have to decrease – not increase – the aperture.

John, of course, your post is lighthearted. Forgive me for spotting the slip!
  • Increase aperture. —> Decrease DoF.
  • Decrease aperture. —> Increase DoF.
 
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Multiple subjects NOT in the same focus plane:
  • front bird (right) : 5 metres from camera
  • rear bird (left) : 5.75 metres from camera
  • corner of room : 6.5 metres
  • f/5.7 = no possibility of having both birds in focus ; therefore, take a separate photo of each bird (focus bracketing).
  • Bracketed frames combined in Ps (focus stacking).
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Focus Bracketing
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My understanding of the terminology:
  • focus bracketing : in-camera process of taking multiple photos of same subject/s with varying focus planes.
  • focus stacking : computer technique for blending the bracketed photos into a single image.
 
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