Struggling mightily with focal length and effect it has on dof

[Mark S Abeln]

Great blue herons are stealthy fishers. It's not uncommon for one to stay on a perch like the one in the photo for several minutes waiting patiently for an opportunity to strike.

Oooo I didn’t know that. That’s good to know, because I do see them around here occasionally.

 

[Martin_99]

1. The longer the focal length the smaller the dof will be.

This by itself is a misleading statement because it doesn’t say what happens with the other parameters. Sometimes it is just plain wrong.

Statement is correct. If you say it this way, it's meant that other parameters are the same.

But they cannot ALL remain the same. If we increase focal length, this will affect things like f-number

There is no mention about f-number in original statement. No reason to include it in discussion.

The problem is, I can't take a photograph without f-number on my camera being set to some value. Not including it in discussion doesn't help me taking photographs.

There is fairly simple logic behind. If something is not mentioned in such statement, no need to include it as it logically remain constant. You can add the aperture for yourself, but it change nothing.

and magnification.

Magnification could remain constant, or getting naturally bigger as you increase the focal length (in case of the same focus distance). In both cases is statement valid - DoF become smaller.

I disagree. Keeping magnification (some people prefer "framing") constant means that DOF can be independent of focal length. A practical example is using a 70-200 f/2.8 lens on full frame for a head-and-shoulders portrait. If the f-number is fixed at f/2.8, running back and forth trying to increase DOF while keeping the framing constant would be a waste of time. It might be a useful thing to do for other reasons but not for DOF.

So if framing and aperture is constant, you can change the DoF only by zooming (change of focal length) means, longer the focal length, smaller the Dof. Seems that you agree with original statement here.

Sorry, seems that logic and common sense is missing from your side, making the discussion pointless.

Can you name an example when the statement "The longer the focal length the smaller the dof will be." is plain wrong?

Sure. When comparing photos taken on different formats.

We can either let them slide or try keeping them constant by changing something else like increasing the entrance pupil to keep the f-number constant or increasing focus distance to keep magnification constant.

Otherwise statements would have to be really long .

better long than meaningless.

 

[PGH423]

info in next image.

You've chosen an excellent camera for wildlife photography and you've come to the right place for help. Others have pointed out two key issues going on here, but I'll give more info since I know this camera pretty well and have had lots of trial and error.

1 - The focus is on the background. You can see the needles in a few of the leaves more clearly than anything else in the scene. The camera should definitely focus on this bird if you have subject detection enabled, have then set it to detect animals, and have the bird within whatever focus area you have selected. You will have a slightly lower hit rate with the subject on the edge of the frame like this, though. The camera should also focus on the eye (but that will be a lower hit rate) if you have enabled eye detection. Focus can miss, though. If this scene was important to me, I would probably have at least 100 shots...about 5 "identical" shots of 20 different compositions.

2 - This is a secondary issue but you are too far from the subject to get excellent detail at 214 mm, especially since it appears you have already cropped almost half the image out (either that or you are shooting at a reduced jpg resolution, which is a bad idea for wildlife photography). In this situation, I probably would take a few shots of the heron but would have modest expectations for image quality and would mostly look for closer subjects.

Also, once you think you have nailed several shots, you then should review the images (playback, view through the evf, and magnify to see if the focus is indeed sharp). "Wild Alaska" has some good YouTube instructional videos on the Canon R7. Keep shooting and posting!

--
My Flickr Page: https://flic.kr/ps/22miQH
My Instagram Page: https://www.instagram.com/leejmarkowitz/
Instagram name: @leejmarkowitz

 

[Bill Ferris]

1. The longer the focal length the smaller the dof will be.

This by itself is a misleading statement because it doesn’t say what happens with the other parameters. Sometimes it is just plain wrong.

Statement is correct. If you say it this way, it's meant that other parameters are the same. Otherwise statements would have to be really long .

These discussions are always taken a bit off course by the way folks use language. I'm gonna assume that by, "other parameters are the same," you're including the f-stop. If we zoom a 70-200mm f/2.8 lens from 70mm f/2.8 to 200mm f/2.8, the depth of field at 200mm f/2.8 will be less (shallower) than at 70mm f/2.8.

The depth of field will be shallower...but not why some (most?) people think. Some folks will say, "All that changed was focal length. Aperture and distance to subject remained constant. The change in focal length caused the change in depth of field." And while those folks are correct that depth of field changed, they're incorrect about the cause of the change.

It's common in photography circles for folks to use the word, aperture, to mean the f-stop; f/2.8, f/4 and so on. However, f/2.8 and other f-stops aren't apertures. They're an equation for determining the diameter of the lens's virtual entrance pupil. That number - the virtual entrance pupil diameter - is the lens's aperture.

Taking this into consideration, there's another factor that changes when we zoom from 70mm f/2.8 to 200mm f/2.8. Focal length changes. Aperture also changes. It changes from (70/2.8=25) 25mm to (200/2.8=71) 71mm and it's the larger aperture (virtual entrance pupil diameter) that causes the change in depth of field; not the change in focal length.

If we change focal length from 70mm to 200mm and keep aperture the same by changing the f-stop from f/2.8 at 70mm to f/8 at 200mm, both photos will be made with lenses using 25mm virtual entrance pupil diameters; 25mm apertures. And those photos will have the same depth of field.

It's not the change in focal length that produces the change in depth of field. It's the change in the size of the virtual entrance pupil, the change in real aperture.

Here's a post from a few years ago illustrating this with some photos: https://www.dpreview.com/forums/post/64536294

 

[chrisfisheye]

It's not the change in focal length that produces the change in depth of field. It's the change in the size of the virtual entrance pupil, the change in real aperture.

Not really.

Though what you say is partially right, I mean if we consider that the f# is constant then when we use longer focal, the change in aperture diameter will contribute to the change of dof. But also the smaller AOV contributes !!!

The proof: instead of considering that f# is constant , consider that the aperture size is constant. The dof will be also shallower...

In every case, the statement that longer FL gives shallower dof without specific assumptions is correct ofc.

Here's a post from a few years ago illustrating this with some photos: https://www.dpreview.com/forums/post/64536294

 

[Bill Ferris]

It's not the change in focal length that produces the change in depth of field. It's the change in the size of the virtual entrance pupil, the change in real aperture.

Not really.

Yes, really.

Though what you say is partially right, I mean if we consider that the f# is constant then when we use longer focal, the change in aperture diameter will contribute to the change of dof. But also the smaller AOV contributes !!!

As the photos in the linked post illustrate, using the same virtual entrance pupil diameter (aperture) at different focal lengths produces images with the same depths of field.

The proof: instead of considering that f# is constant , consider that the aperture size is constant. The dof will be also shallower...

If both distance to subject and virtual entrance pupil diameter remain constant, as the photos in the linked post illustrate, depth of will be perceived as the same.

In every case, the statement that longer FL gives shallower dof without specific assumptions is correct ofc.

As demonstrated, it's not correct.

Here's a post from a few years ago illustrating this with some photos: https://www.dpreview.com/forums/post/64536294

 

[J A C S]

1. The longer the focal length the smaller the dof will be.

This by itself is a misleading statement because it doesn’t say what happens with the other parameters. Sometimes it is just plain wrong.

Statement is correct. If you say it this way, it's meant that other parameters are the same.

But they cannot ALL remain the same. If we increase focal length, this will affect things like f-number

There is no mention about f-number in original statement. No reason to include it in discussion.

The problem is, I can't take a photograph without f-number on my camera being set to some value. Not including it in discussion doesn't help me taking photographs.

There is fairly simple logic behind. If something is not mentioned in such statement, no need to include it as it logically remain constant.

Like framing? Or like the aperture size (not f-stop)? Or like the FOV (but it cannot), etc.?

 

[chrisfisheye]

It's not the change in focal length that produces the change in depth of field. It's the change in the size of the virtual entrance pupil, the change in real aperture.

Not really.

Yes, really.

Though what you say is partially right, I mean if we consider that the f# is constant then when we use longer focal, the change in aperture diameter will contribute to the change of dof. But also the smaller AOV contributes !!!

As the photos in the linked post illustrate, using the same virtual entrance pupil diameter (aperture) at different focal lengths produces images with the same depths of field.

The proof: instead of considering that f# is constant , consider that the aperture size is constant. The dof will be also shallower...

If both distance to subject and virtual entrance pupil diameter remain constant, as the photos in the linked post illustrate, depth of will be perceived as the same.

In every case, the statement that longer FL gives shallower dof without specific assumptions is correct ofc.

As demonstrated, it's not correct.

Here's a post from a few years ago illustrating this with some photos: https://www.dpreview.com/forums/post/64536294

Dem Bell will certainly confirm how good are your illustrations to proove your various points...

Loading…

www.dpreview.com

I agree with what Dem Bell said in the linked thread, spot on

 

[Bill Ferris]

It's not the change in focal length that produces the change in depth of field. It's the change in the size of the virtual entrance pupil, the change in real aperture.

Not really.

Yes, really.

Though what you say is partially right, I mean if we consider that the f# is constant then when we use longer focal, the change in aperture diameter will contribute to the change of dof. But also the smaller AOV contributes !!!

As the photos in the linked post illustrate, using the same virtual entrance pupil diameter (aperture) at different focal lengths produces images with the same depths of field.

The proof: instead of considering that f# is constant , consider that the aperture size is constant. The dof will be also shallower...

If both distance to subject and virtual entrance pupil diameter remain constant, as the photos in the linked post illustrate, depth of will be perceived as the same.

In every case, the statement that longer FL gives shallower dof without specific assumptions is correct ofc.

As demonstrated, it's not correct.

Here's a post from a few years ago illustrating this with some photos: https://www.dpreview.com/forums/post/64536294

Dem Bell will certainly confirm how good are your illustrations to proove your various points...

https://www.dpreview.com/forums/post/64537520

I agree with what Dem Bell said in the linked thread, spot on

So you deny that depth of field is a perceived quality of a photo? You deny that the depth of field in the first and third photos of my post have the same or - at worst - similar apparent depths of field.

You assert that a flat image with literally zero depth has a measurable depth of field. You assert that despite the obvious differences between the second and third photos in my post, that focal length, in and of itself, is an equal factor in determining depth of field.

If you refuse to acknowledge the reality illustrated by the photos in my 2020 post, that is, of course, your choice. You're free to do so. But nobody else, here, is obliged to accept your unsupported assertions.

 

[chrisfisheye]

It's not the change in focal length that produces the change in depth of field. It's the change in the size of the virtual entrance pupil, the change in real aperture.

Not really.

Yes, really.

Though what you say is partially right, I mean if we consider that the f# is constant then when we use longer focal, the change in aperture diameter will contribute to the change of dof. But also the smaller AOV contributes !!!

As the photos in the linked post illustrate, using the same virtual entrance pupil diameter (aperture) at different focal lengths produces images with the same depths of field.

The proof: instead of considering that f# is constant , consider that the aperture size is constant. The dof will be also shallower...

If both distance to subject and virtual entrance pupil diameter remain constant, as the photos in the linked post illustrate, depth of will be perceived as the same.

In every case, the statement that longer FL gives shallower dof without specific assumptions is correct ofc.

As demonstrated, it's not correct.

Here's a post from a few years ago illustrating this with some photos: https://www.dpreview.com/forums/post/64536294

Dem Bell will certainly confirm how good are your illustrations to proove your various points...

https://www.dpreview.com/forums/post/64537520

I agree with what Dem Bell said in the linked thread, spot on

So you deny that depth of field is a perceived quality of a photo? You deny that the depth of field in the first and third photos of my post have the same or - at worst - similar apparent depths of field.

You assert that a flat image with literally zero depth has a measurable depth of field. You assert that despite the obvious differences between the second and third photos in my post, that focal length, in and of itself, is an equal factor in determining depth of field.

If you refuse to acknowledge the reality illustrated by the photos in my 2020 post, that is, of course, your choice. You're free to do so. But nobody else, here, is obliged to accept your unsupported assertions.

You wrote a "massive post with 2/3 being wrong", I am just quoting Dem Bell.

Honestly, I can not do better than his post, really. Everything is written, just read it. Dem Bell is in this thread.

 

[Alfn2]

I consider that this sentence is of course 100% correct:

The longer the focal length the smaller the dof will be

That sentence may be true or it may be false, it all depends on the additional assumptions that are made.

People often say "if everything else remains the same", but that is an impossible condition in this situation. For example, if you keep the image of your subject the same size in the frame, then it is not possible to also keep the subject distance the same.

In either case: the longer the focal length the shallower the DOF will be.

 

[Alfn2]

But first tell the bird to keep perfectly still. :-D

indeed.

That technique might work with landscape photography, ideally using a tripod, but not with wildlife.

Great blue herons are stealthy fishers. It's not uncommon for one to stay on a perch like the one in the photo for several minutes waiting patiently for an opportunity to strike.

So true. And the Grey Heron is even more patient. These things are important to know.

 

[Dem Bell]

1. The longer the focal length the smaller the dof will be.

This by itself is a misleading statement because it doesn’t say what happens with the other parameters. Sometimes it is just plain wrong.

Statement is correct. If you say it this way, it's meant that other parameters are the same. Otherwise statements would have to be really long .

These discussions are always taken a bit off course by the way folks use language. I'm gonna assume that by, "other parameters are the same," you're including the f-stop. If we zoom a 70-200mm f/2.8 lens from 70mm f/2.8 to 200mm f/2.8, the depth of field at 200mm f/2.8 will be less (shallower) than at 70mm f/2.8.

The depth of field will be shallower...but not why some (most?) people think. Some folks will say, "All that changed was focal length. Aperture and distance to subject remained constant. The change in focal length caused the change in depth of field." And while those folks are correct that depth of field changed, they're incorrect about the cause of the change.

It's common in photography circles for folks to use the word, aperture, to mean the f-stop; f/2.8, f/4 and so on. However, f/2.8 and other f-stops aren't apertures. They're an equation for determining the diameter of the lens's virtual entrance pupil. That number - the virtual entrance pupil diameter - is the lens's aperture.

Taking this into consideration, there's another factor that changes when we zoom from 70mm f/2.8 to 200mm f/2.8. Focal length changes. Aperture also changes. It changes from (70/2.8=25) 25mm to (200/2.8=71) 71mm and it's the larger aperture (virtual entrance pupil diameter) that causes the change in depth of field; not the change in focal length.

This was wrong 3 years ago and it is still wrong.

If we change focal length from 70mm to 200mm and keep aperture the same by changing the f-stop from f/2.8 at 70mm to f/8 at 200mm, both photos will be made with lenses using 25mm virtual entrance pupil diameters; 25mm apertures. And those photos will have the same depth of field.

Have you tried these numbers in a DOF calculator? Please do, you will see that for the same subject distance the results differ by a factor of 3 so. Not the same at all.

It's not the change in focal length that produces the change in depth of field. It's the change in the size of the virtual entrance pupil, the change in real aperture.

I have got no idea how one would come to this conclusion when looking at any formula for DOF. DOF is "caused" by a combination of parameters, at least three parameters. Singling out one of them and saying "He did it!" makes no sense.

Here's a post from a few years ago illustrating this with some photos: https://www.dpreview.com/forums/post/64536294

--
Bill Ferris Photography
Flagstaff, AZ
http://www.billferris.photoshelter.com

 

[FrancoD]

When you see a photo like that that appears to have everything in focus it is because it was taken at a close distance, say 5 metres away, with a wide lens , something like a 16mm for your APS body.

BTW, to get closer, don't look at the bird directly, walk slowly and raise your lens to your eye very slowly. Some birds are more accostomed to humans then others and usualy are easier to approach when busy looking for food.

 

[Bill Ferris]

It's not the change in focal length that produces the change in depth of field. It's the change in the size of the virtual entrance pupil, the change in real aperture.

Not really.

Yes, really.

Though what you say is partially right, I mean if we consider that the f# is constant then when we use longer focal, the change in aperture diameter will contribute to the change of dof. But also the smaller AOV contributes !!!

As the photos in the linked post illustrate, using the same virtual entrance pupil diameter (aperture) at different focal lengths produces images with the same depths of field.

The proof: instead of considering that f# is constant , consider that the aperture size is constant. The dof will be also shallower...

If both distance to subject and virtual entrance pupil diameter remain constant, as the photos in the linked post illustrate, depth of will be perceived as the same.

In every case, the statement that longer FL gives shallower dof without specific assumptions is correct ofc.

As demonstrated, it's not correct.

Here's a post from a few years ago illustrating this with some photos: https://www.dpreview.com/forums/post/64536294

Dem Bell will certainly confirm how good are your illustrations to proove your various points...

https://www.dpreview.com/forums/post/64537520

I agree with what Dem Bell said in the linked thread, spot on

So you deny that depth of field is a perceived quality of a photo? You deny that the depth of field in the first and third photos of my post have the same or - at worst - similar apparent depths of field.

You assert that a flat image with literally zero depth has a measurable depth of field. You assert that despite the obvious differences between the second and third photos in my post, that focal length, in and of itself, is an equal factor in determining depth of field.

If you refuse to acknowledge the reality illustrated by the photos in my 2020 post, that is, of course, your choice. You're free to do so. But nobody else, here, is obliged to accept your unsupported assertions.

You wrote a "massive post with 2/3 being wrong", I am just quoting Dem Bell.

Do other people always do your thinking and speaking for you?

Honestly, I can not do better than his post, really. Everything is written, just read it. Dem Bell is in this thread.

Apparently, you are incapable of forming your own opinions or of supporting them.

 

[chutestrate]

Thank you. I"m shooting in raw and jpeg and no cropping. I had it at 400mm but couldn't set the image as I wanted. I wanted to capture the reflection, and bird on the log. Just seemed a cool composition. I am definitely learning about needing to check images before I leave a site. I took one today that I am unhappy with the focus. It was a good shot, and I can't use it.

You've chosen an excellent camera for wildlife photography and you've come to the right place for help. Others have pointed out two key issues going on here, but I'll give more info since I know this camera pretty well and have had lots of trial and error.

1 - The focus is on the background. You can see the needles in a few of the leaves more clearly than anything else in the scene. The camera should definitely focus on this bird if you have subject detection enabled, have then set it to detect animals, and have the bird within whatever focus area you have selected. You will have a slightly lower hit rate with the subject on the edge of the frame like this, though. The camera should also focus on the eye (but that will be a lower hit rate) if you have enabled eye detection. Focus can miss, though. If this scene was important to me, I would probably have at least 100 shots...about 5 "identical" shots of 20 different compositions.

2 - This is a secondary issue but you are too far from the subject to get excellent detail at 214 mm, especially since it appears you have already cropped almost half the image out (either that or you are shooting at a reduced jpg resolution, which is a bad idea for wildlife photography). In this situation, I probably would take a few shots of the heron but would have modest expectations for image quality and would mostly look for closer subjects.

Also, once you think you have nailed several shots, you then should review the images (playback, view through the evf, and magnify to see if the focus is indeed sharp). "Wild Alaska" has some good YouTube instructional videos on the Canon R7. Keep shooting and posting!

 

[Bill Ferris]

1. The longer the focal length the smaller the dof will be.

This by itself is a misleading statement because it doesn’t say what happens with the other parameters. Sometimes it is just plain wrong.

Statement is correct. If you say it this way, it's meant that other parameters are the same. Otherwise statements would have to be really long .

These discussions are always taken a bit off course by the way folks use language. I'm gonna assume that by, "other parameters are the same," you're including the f-stop. If we zoom a 70-200mm f/2.8 lens from 70mm f/2.8 to 200mm f/2.8, the depth of field at 200mm f/2.8 will be less (shallower) than at 70mm f/2.8.

The depth of field will be shallower...but not why some (most?) people think. Some folks will say, "All that changed was focal length. Aperture and distance to subject remained constant. The change in focal length caused the change in depth of field." And while those folks are correct that depth of field changed, they're incorrect about the cause of the change.

It's common in photography circles for folks to use the word, aperture, to mean the f-stop; f/2.8, f/4 and so on. However, f/2.8 and other f-stops aren't apertures. They're an equation for determining the diameter of the lens's virtual entrance pupil. That number - the virtual entrance pupil diameter - is the lens's aperture.

Taking this into consideration, there's another factor that changes when we zoom from 70mm f/2.8 to 200mm f/2.8. Focal length changes. Aperture also changes. It changes from (70/2.8=25) 25mm to (200/2.8=71) 71mm and it's the larger aperture (virtual entrance pupil diameter) that causes the change in depth of field; not the change in focal length.

This was wrong 3 years ago and it is still wrong.

Your understanding of depth of field is lacking.

If we change focal length from 70mm to 200mm and keep aperture the same by changing the f-stop from f/2.8 at 70mm to f/8 at 200mm, both photos will be made with lenses using 25mm virtual entrance pupil diameters; 25mm apertures. And those photos will have the same depth of field.

Have you tried these numbers in a DOF calculator? Please do, you will see that for the same subject distance the results differ by a factor of 3 so. Not the same at all.

This is where your understanding of the subject is limited. A measurable depth of field only exists in the image projected by the lens. A photograph is a two-dimensional representation of that image. It literally has no depth. The only depth of field in a photo is that which is perceived by the viewer.

The viewer takes multiple visual cues into account when deciding what depth of field is represented in the photo and how the respective depths of field in two photos are. As the photos I posted three years ago clearly demonstrate, photographs made from the same perspective, focused on the same point, using different focal lengths but the same virtual entrance pupil diameter (aperture) will be perceived as having the same or similar depths of field.

This is an easy test to set up at and perform at home. Do it and see for yourself: changing focal length, alone, does not change the perceived depth of field in a photograph. Changing the distance to the subject or the lens aperture does.

It's not the change in focal length that produces the change in depth of field. It's the change in the size of the virtual entrance pupil, the change in real aperture.

I have got no idea how one would come to this conclusion when looking at any formula for DOF. DOF is "caused" by a combination of parameters, at least three parameters. Singling out one of them and saying "He did it!" makes no sense.

Some people understand that depth of field calculators apply to the image projected by the lens, but not to a 2D image that has no depth and, therefore, no depth of field. Depth of field is a perceived quality of a photo.

Here's a post from a few years ago illustrating this with some photos: https://www.dpreview.com/forums/post/64536294

 

[PGH423]

Thank you. I"m shooting in raw and jpeg and no cropping. I had it at 400mm but couldn't set the image as I wanted. I wanted to capture the reflection, and bird on the log. Just seemed a cool composition. I am definitely learning about needing to check images before I leave a site. I took one today that I am unhappy with the focus. It was a good shot, and I can't use it.

You've chosen an excellent camera for wildlife photography and you've come to the right place for help. Others have pointed out two key issues going on here, but I'll give more info since I know this camera pretty well and have had lots of trial and error.

1 - The focus is on the background. You can see the needles in a few of the leaves more clearly than anything else in the scene. The camera should definitely focus on this bird if you have subject detection enabled, have then set it to detect animals, and have the bird within whatever focus area you have selected. You will have a slightly lower hit rate with the subject on the edge of the frame like this, though. The camera should also focus on the eye (but that will be a lower hit rate) if you have enabled eye detection. Focus can miss, though. If this scene was important to me, I would probably have at least 100 shots...about 5 "identical" shots of 20 different compositions.

2 - This is a secondary issue but you are too far from the subject to get excellent detail at 214 mm, especially since it appears you have already cropped almost half the image out (either that or you are shooting at a reduced jpg resolution, which is a bad idea for wildlife photography). In this situation, I probably would take a few shots of the heron but would have modest expectations for image quality and would mostly look for closer subjects.

Also, once you think you have nailed several shots, you then should review the images (playback, view through the evf, and magnify to see if the focus is indeed sharp). "Wild Alaska" has some good YouTube instructional videos on the Canon R7. Keep shooting and posting!

You've gotten a lot of replies - I'm glad you stuck around for all of it!

The reason I thought this was either cropped or a reduced resolution JPG is that it is a 32.5 mp camera, but the dimensions listed are 4800x3200 pixels (which works out to 15.36 mp).

--
My Flickr Page: https://flic.kr/ps/22miQH
My Instagram Page: https://www.instagram.com/leejmarkowitz/
Instagram name: @leejmarkowitz

 

[BackToNature1]

When you see a photo like that that appears to have everything in focus it is because it was taken at a close distance, say 5 metres away, with a wide lens , something like a 16mm for your APS body.

BTW, to get closer, don't look at the bird directly, walk slowly and raise your lens to your eye very slowly. Some birds are more accostomed to humans then others and usualy are easier to approach when busy looking for food.

Tons of folks want that Reflection of the Bird in the Water. Look at the reading of Focal Length, 214mm, so apparently the OP has 186MM left to play with, but that would have wiped out my interpretation of the OP intent with stated possible composition. So I hardly think this was a issue of wanting to get closer. Otherwise the OP could have used the entire Focal Length, assuming the data is correct.



So I highly doubt this was picture taken at 5meters and or some 16 odd feet or so away. So it's not just about getting closer, but what we actually want in the frame. I would have to reread all the OP comments to see if that was the OP actually intent.

 

[J A C S]

Thank you. I"m shooting in raw and jpeg and no cropping. I had it at 400mm but couldn't set the image as I wanted. I wanted to capture the reflection, and bird on the log. Just seemed a cool composition. I am definitely learning about needing to check images before I leave a site. I took one today that I am unhappy with the focus. It was a good shot, and I can't use it.

The reflected bird is in focus, the reason it appears not so sharp is because the reflection is not so good.