DoF - group animal portraits

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MarkG

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I sometimes come across group portrait opportunities: a pair of owls, a mother bird and a chick, etc.

Often, the two subjects are in slightly different planes of focus, so focusing on one's eye could render the other one OOF.

With long (600mm to 800mm) focal lengths, the DoF is rather shallow, especially with subjects that fill the frame, close-up

So far the only technique I've used is closing down the aperture and guessing at its value. Normally, I'd use 600mm F6.3, but for groups I could try F8 or F11, given enough light. Still, often DoF is not deep enough.

Does anyone have a better, more accurate approach/technique other than relying on experience/feel for what the aperture should be?


(I can also see this as an opportunity for camera manufacturers, i.e. "group portrait mode". A camera can take two shots, each focused on a different member of the group, very quickly. Perhaps 10-20ms apart. The resulting raw files can then be focus stacked. Or, a camera can calculate and automatically set an appropriate aperture value based on the two distances)
 
Maybe too simple, but how about pressing the DOF preview button on the camera? As to depth compositing, it's getting simpler these days, in the software provided by the camera maker and programs like photoshop or Zerene or Helicon.
 
One option is to take two shots with focus on each subject and then overlay them in Photoshop.

A problem is also that the calculated DOF is partly in front of the point of focus and partly behind it so the usable DOF can often the half of what is calculated.
 
I sometimes come across group portrait opportunities: a pair of owls, a mother bird and a chick, etc.

Often, the two subjects are in slightly different planes of focus, so focusing on one's eye could render the other one OOF.

With long (600mm to 800mm) focal lengths, the DoF is rather shallow, especially with subjects that fill the frame, close-up

So far the only technique I've used is closing down the aperture and guessing at its value. Normally, I'd use 600mm F6.3, but for groups I could try F8 or F11, given enough light. Still, often DoF is not deep enough.

Does anyone have a better, more accurate approach/technique other than relying on experience/feel for what the aperture should be?


(I can also see this as an opportunity for camera manufacturers, i.e. "group portrait mode". A camera can take two shots, each focused on a different member of the group, very quickly. Perhaps 10-20ms apart. The resulting raw files can then be focus stacked. Or, a camera can calculate and automatically set an appropriate aperture value based on the two distances)
Sounds like you've got a good handle on the question. Basically, assuming you can't reposition to get the subjects closer to the same distance from the camera your options are to stop down or shoot multiple images and focus stack. I'll generally try to stop down first but if the subjects are relatively still I'll shoot multiple images, each focused on one subject and stack them in post. I've had good luck doing that with grazing mammals and perched birds, especially owls that don't move around a lot.
 
FWIW, here's one of those focus stacks from a couple of years back that I've posted before. Shooting my 600mm plus TC I just couldn't stop down enough to keep both owls sharp so I took two images and did a quick and simple focus stack in PS. It doesn't have to be as complex as a macro focus stack, for instance this image was just two shots combined using Photoshops, Auto-Blend Layers option.

Z62_5933--20210514-Edit-2.jpg
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Sounds like you've got a good handle on the question. Basically, assuming you can't reposition to get the subjects closer to the same distance from the camera your options are to stop down or shoot multiple images and focus stack. I'll generally try to stop down first but if the subjects are relatively still I'll shoot multiple images, each focused on one subject and stack them in post. I've had good luck doing that with grazing mammals and perched birds, especially owls that don't move around a lot.
I will try this in the field. Thank you!
 
Maybe too simple, but how about pressing the DOF preview button on the camera? As to depth compositing, it's getting simpler these days, in the software provided by the camera maker and programs like photoshop or Zerene or Helicon.
I will try focus stacking, but the DoF preview is really hard to judge in the viewfinder.
 
I'm eager to try the 'focus stacking' option.

Without risking recomposing a handheld shot, what are the options for taking multiple images of subjects? I can think of the following:
  1. Using the camera's focus-stacking option to take ±10 exposures at ~5mm gaps and choosing only those that are suitable.
    Possible on most high-end mirrorless cameras.

  2. Using the eye-controlled focus option to choose one subject and then the next.
    Possible on very few mirrorless cameras. (I had it on a 1990s Nikon film SLR.)
Option #2 refers to where the photographer's eye looks to set the focus point; not to be confused with eye-detect focus.

… David
 
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I'm eager to try the 'focus stacking' option.

Without risking recomposing a handheld shot, what are the options for taking multiple images of, hopefully static, subjects? I can think of the following:
  1. Using the focus-stacking option in a mirrorless camera to take ±10 exposures at ~5mm gaps and choosing only those that are suitable.
  2. Using the eye-controlled focus option to choose one subject and then the next (not possible on most mirrorless cameras).
Option #2 refers to the photographer's eye detecting where the focus point should be; not to be confused with eye-detect focus.

… David
As long as you're pretty steady and shoot a bit loose (IOW, don't frame the image super tight in the field, leave some breathing room) it's not too hard to align the images even for handheld shots. Just use whatever focus mode you prefer to focus on each subject in turn (eye tracking, single point moved with a joystick, etc.) and shoot two images before the subjects move too much.

In addition to Auto-Blend layers, Photoshop can Auto-Align layers and you can always use the Move tool to manually align layers that may not be perfectly aligned when shooting. It may mean some cropping after the alignment but if you're not completely filling the frame that's not usually a big deal.
 
My OM-1.2 can do a pretty fast focus bracketing job with 100-400mm. I've used it before for Macro stacking, but never for animals. After watching Steve's tutorial, it seems like it should be possible. Pick the subject closest to you and go, OM-1 should do the rest. Will try...
 
I sometimes come across group portrait opportunities: a pair of owls, a mother bird and a chick, etc.

Often, the two subjects are in slightly different planes of focus, so focusing on one's eye could render the other one OOF.

With long (600mm to 800mm) focal lengths, the DoF is rather shallow, especially with subjects that fill the frame, close-up

So far the only technique I've used is closing down the aperture and guessing at its value. Normally, I'd use 600mm F6.3, but for groups I could try F8 or F11, given enough light. Still, often DoF is not deep enough.

Does anyone have a better, more accurate approach/technique other than relying on experience/feel for what the aperture should be?


(I can also see this as an opportunity for camera manufacturers, i.e. "group portrait mode". A camera can take two shots, each focused on a different member of the group, very quickly. Perhaps 10-20ms apart. The resulting raw files can then be focus stacked. Or, a camera can calculate and automatically set an appropriate aperture value based on the two distances)
I sometimes use focus peaking (with sensitivity set to 3) to get a visual indication of depth of field. If the group isn’t likely to be included in the DOF then focus stacking is the best approach if the critters are relatively still.
 
As long as you're pretty steady and shoot a bit loose (IOW, don't frame the image super tight in the field, leave some breathing room) it's not too hard to align the images even for handheld shots. Just use whatever focus mode you prefer to focus on each subject in turn (eye tracking, single point moved with a joystick, etc.) and shoot two images before the subjects move too much.

In addition to Auto-Blend layers, Photoshop can Auto-Align layers and you can always use the Move tool to manually align layers that may not be perfectly aligned when shooting. It may mean some cropping after the alignment but if you're not completely filling the frame that's not usually a big deal.
Yep, exactly. I focus stack birds a lot. One of my favorite photos is an owl that perched WA too close to me. I did a 3 shot vertical pano handheld that turned out great.

But I also focus stack herons and egrets frequently to get their reflection. Technique doesn’t have to be perfect for the images to align, but you should definitely give yourself some room to crop.
 
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