Focusing on Reflections in Water as it relates to a landscape image

[Brownbear]

My understanding of the placement of the focal point in a landscape image (without doing any calculations) is that focusing at a point about 1/3 of the way into the image in the field of view is that the field of view will carry through 1/3 of the distance from my chosen focal point towards my camera, and 2/3 of the distance from my chosen focal point into the grand vista beyond that point.

And that the depth of field needed to keep my chosen area of the image in sharp focus is dependent upon the aperture I choose. If I choose say F22 and choose a focus point 8 meters from me the focus will extend about 3 meters towards the image in my camera and about 6 meters beyond my focus point. If I choose F4 the area of sharp focus will be smaller.


Most recently I tried photographing a landscape image with a wide angle lens (focal length 10 mm) and I focused on the reflection of a cloud in the water in close proximity (best guess 1-3 meters from me) using an aperture of F7 and the whole scene was in focus. Is that simply because the distance of the boats and mountains in the background was so great that my chosen aperture combined with the use of a wide angle lens doesn't truly matter? ie; I was focusing on infinity even though I was focusing on the reflection of the cloud?

Which brings me to the use of a wide angle lens (wide angle of view) and ones chosen focusing point in a landscape. Let's say I was photographing a scene of a ocean with distant mountains in the background, with whales breaching right in front of me. If I wanted the whales to appear larger than life I would place my focus point on the breaching whales just 4 meters in front of me. Using the focal length calculator and entering a distance of 4 meters and 8 meters (to represent the size of the whale) provides an answer of 11.2 mm for my chosen focal length.

For the breaching whale scenario would I still achieve sharp focus on the whales and throughout most of the image and sufficient depth of field throughout the image whether I chose an aperture of F8 or F22 (well perhaps just a sharpness of the distant mountains in the background) using a wide angle lens set at 11.2 mm? And a focal length of 5mm would allow more of the foreground to be in focus right in front of me? And a focal length of 20mm would decrease the depth of field?

If the answer is yes, is it possible to explain the relationship of my chosen focal length, chosen aperture and distance in a simple manner that would enhance my understanding so that when I see such a scene (well perhaps a dog frolicking in the water is more likely ) I can approach choosing my aperture and focal point with greater ease?

I've reviewed the tutorials on this subject and I still feel like I'm missing something. Hence I'm hoping that my the convoluted question will shed light on what I'm not understanding about the subject matter.

Thank you.

[Mike Buckley]

I recommend that you place some objects in your yard, hopefully at least three of them at least one meter apart. The more the better. Then very systematically do the following:

1) Use a particular focal length and distance to an object, changing only the aperture using many settings.

2) Use a particular focal length and aperture, changing only the distance. Begin with a distance of no more than one meter and make each subsequent distance about twice as large.

3) Use a particular aperture and distance to an object, changing only the focal length. Start with your shortest focal length and make each subsequent focal length about twice as long.

Once you do that and examine the results on your computer, you'll probably have a better feel for depth of field.

Regarding the reflection of the clouds, go back to the other thread where I mentioned that the focusing distance for reflections are different. In other words, if a branch had been floating in the water in the middle of the reflection of the cloud, it would have been possible to use a large aperture and longer focal length that would have included the branch but not the reflection in the depth of field and vice versa.

[Shadowman]

Christina,

This link has examples of the image you are trying to achieve and also the settings used by the photographers.

http://www.shutterbug.com/content/deep-depth-field

Also, Bryan Peterson has a good book on achieving deep depth of field.

http://www.kinokuniya.com/sg/index.p...=9780770433055

The Peterson book will change the way you shoot.

[Brownbear]

Hi Mike,

I will do that exercise as soon as it stops raining. Hopefully it will clear things up.

With respect to the reflection of the cloud. I missed the referral to an object and I've been thinking about that cloud for 2 days now.

Thank you.

[Brownbear]

Thank you John.

I have Bryan Peterson's Understanding Exposure, likely the same book with a different title? If not I will check it out (and review the links)

Christina,

This link has examples of the image you are trying to achieve and also the settings used by the photographers.

http://www.shutterbug.com/content/deep-depth-field

Also, Bryan Peterson has a good book on achieving deep depth of field.

http://www.kinokuniya.com/sg/index.p...=9780770433055

The Peterson book will change the way you shoot.

[Mike Buckley]

With respect to the reflection of the cloud.

The focusing distance pertaining to a reflection is the distance of the camera to the source object plus the distance of the source object to its reflection.

Another exercise, though one that can be conducted indoors: Set up a mirror at least two meters away from you. Set any object to the right or left of it. As you see yourself in the mirror, use a focal length that fills your head and shoulders in the frame. Use the largest aperture. I doubt that you'll get both the object and the reflection in focus. That's because the focusing distance of the reflection is twice as far as the focusing distance of the other subject.

[Brownbear]

Hi Mike,

I have a long hallway so I did the exercise indoors with fruit and it is normal, ie; as expected and something that I can't translate into something meaningful and practical for photographing a landscape in terms of focusing 1/3 of the way in... other than that it is definitely clear that with great distances the choice of aperture and focal length isn't important.

1. Set focal length and distance - a larger aperture creates a larger DOF

2. Set focal length and aperture - being farther away creates a larger DOF

3. Set aperture and distance - a larger focal length creates less DOF

I will try the cloud exercise because that has me thoroughly puzzled.

Thank you.

I recommend that you place some objects in your yard, hopefully at least three of them at least one meter apart. The more the better. Then very systematically do the following:

1) Use a particular focal length and distance to an object, changing only the aperture using many settings.

2) Use a particular focal length and aperture, changing only the distance. Begin with a distance of no more than one meter and make each subsequent distance about twice as large.

3) Use a particular aperture and distance to an object, changing only the focal length. Start with your shortest focal length and make each subsequent focal length about twice as long.

Once you do that and examine the results on your computer, you'll probably have a better feel for depth of field.

Regarding the reflection of the clouds, go back to the other thread where I mentioned that the focusing distance for reflections are different. In other words, if a branch had been floating in the water in the middle of the reflection of the cloud, it would have been possible to use a large aperture and longer focal length that would have included the branch but not the reflection in the depth of field and vice versa.

[Mike Buckley]

I have a long hallway so I did the exercise indoors with fruit and it is normal, ie; as expected and something that I can't translate into something meaningful and practical for photographing a landscape.

That's because your hallway isn't long enough. For practical results relating to photographing a landscape, you need to be photographing outdoors where the distances are far, far greater.

[Mike Buckley]

I will try the cloud exercise because that has me thoroughly puzzled.

For the record, I've also never understood it because I'm not a physicist specializing in the physics of light. I only accept the facts as truth. However, photographing a mirror and not being able to keep both the mirror's wooden frame and the mirror's reflected image in focus when using a long lens and a large aperture at a relatively short distance sold me on the different focusing distances as gospel truth.

[Brownbear]

Done... Actually it was impossible to fit the object in the frame when I zoomed in on me, but an picture in the hallway was not in focus. I am having a hard time understanding this one so I will read up on photographing reflections. Perhaps given a little time and more thought, I will eventually understand it.

Thank you for trying.

The focusing distance pertaining to a reflection is the distance of the camera to the source object plus the distance of the source object to its reflection.

Another exercise, though one that can be conducted indoors: Set up a mirror at least two meters away from you. Set any object to the right or left of it. As you see yourself in the mirror, use a focal length that fills your head and shoulders in the frame. Use the largest aperture. I doubt that you'll get both the object and the reflection in focus. That's because the focusing distance of the reflection is twice as far as the focusing distance of the other subject.

[Brownbear]

Our hallway is ~ 11-12 meters long which is longer then the lawn outside. It sounds like I need to visit a sports field to do the exercise but I will do just that when weather clears.

Thank you.

That's because your hallway isn't long enough. For practical results relating to photographing a landscape, you need to be photographing outdoors where the distances are far, far greater.

[Mike Buckley]

Actually it was impossible to fit the object in the frame when I zoomed in on me

Sorry, Christina. My instructions were not clear enough. I should have instructed you to manually focus on the image of your head and shoulders filling the frame and release the shutter. Without making any changes to your camera settings, then move the camera until you can see the other object in the viewfinder. Release the shutter. Look at the two images on your computer or by magnifying them on your camera's LCD. Only the first photo should be in focus. The two images may be so different that you may not even need to release the shutter to see the difference in sharpness when separately pointing the lens at the two subjects.

[Brownbear]

Thank you for sharing. I just tried it again using the frame of the mirror as the object, and yes, agreed impossible. I wish I understood why, but good to know.

For the record, I've also never understood it because I'm not a physicist specializing in the physics of light. I only accept th
e facts as truth. However, photographing a mirror and not being able to keep both the mirror's wooden frame and the mirror's reflected image in focus when using a long lens and a large aperture at a relatively short distance sold me on the different focusing distances as gospel truth.

[Brownbear]

No worries... Replicated. It also works with the frame of the mirror.
Thanks Mike.

Sorry, Christina. My instructions were not clear enough. I should have instructed you to manually focus on the image of your head and shoulders filling the frame and release the shutter. Without making any changes to your camera settings, then move the camera until you can see the other object in the viewfinder. Release the shutter. Look at the two images on your computer or by magnifying them on your camera's LCD. Only the first photo should be in focus. The two images may be so different that you may not even need to release the shutter to see the difference in sharpness when separately pointing the lens at the two subjects.

[Mike Buckley]

Great, Christina! Glad to know the exercise showed you the impact of a reflection when determining focusing distance.

Now you understand that though you thought you were focusing on something "near" you when you focused on the reflection of the cloud, that wasn't at all the case. That focusing distance was the distance from you to the cloud in the sky plus the distance from that cloud to its reflection.

[MrB]

Christina, you can have fun and help your understanding by playing around with this -

http://camerasim.com/apps/camera-simulator/

Philip

[Mike Buckley]

That tool is so cool, Philip!

[Brownbear]

Yes, LOL now I understand which means I will finally get a good nights sleep!

Great, Christina! Glad to know the exercise showed you the impact of a reflection when determining focusing distance.

Now you understand that though you thought you were focusing on something "near" you when you focused on the reflection of the cloud, that wasn't at all the case. That focusing distance was the distance from you to the cloud in the sky plus the distance from that cloud to its reflection.

[Brownbear]

Thanks for sharing Philip... That is really cool. Instant feedback. I will be playing with it.

Christina, you can have fun and help your understanding by playing around with this -

http://camerasim.com/apps/camera-simulator/

Philip

[Digital]

Christina, do you know the 3 variables that influence DOF?



Bruce