Can someone explain how this works?

battletone

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Wow, what is your problem?
 
Wow, what is your problem?

He's only asking about a technical aspect of a photo you took and how such a shallow depth of field was achieved using f/22. No need to get defensive about it.
 
He's only asking about a technical aspect of a photo you took and how such a shallow depth of field was achieved using f/22. No need to get defensive about it.

Am I not being accused of lying?

or maybe the OP and I got off on the wrong foot... Battletone, is this what is happening? A miscommunication?
 
Well not necessarily, his previous post in the other forum was kindof like that, but i neither understand how this happened so i'd love to hear a good explanation
 
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Well not necessarily, his previous post in the other forum was kindof like that, but i neither understand how this happened so i'd love to hear a good explanation

Honestly, I don't know. I am very new with a DSLR and was just trying a lot of different aperature combos... also, it was VERY bright that day.

Not as I see it.

Fair enough... miscommunication then, my apologies.
 
http://www.thephotoforum.com/forum/...allery/182890-amateur-photo-contest-help.html

Image #1

I don't want to jack this thread any further, but I don't understand how this shallow DOF was achieved with a simple 18-55mm lens (I presume the Nikon kit lens?) at 55mm with f22.

It reminds me of the tiltshift effect that people do with Photoshop.
It's explained in this recent thread:

http://www.thephotoforum.com/forum/...allery/182687-leaf-sidewalk-c-c-please-2.html
 
http://www.thephotoforum.com/forum/...allery/182890-amateur-photo-contest-help.html

Image #1

I don't want to jack this thread any further, but I don't understand how this shallow DOF was achieved with a simple 18-55mm lens (I presume the Nikon kit lens?) at 55mm with f22.

It reminds me of the tiltshift effect that people do with Photoshop.
DOF is not a sole function of aperture. Subject distance has a lot to do with it, as does the focal length of the lens.

It's really pretty simple:
DF from the camera to the far limit of DOF are
a1015da206f3ca83e0b4013dcf1fb1d1.png
and
3dd5632cdad928d3b9c2373a4278e164.png
When the subject distance is the hyperfocal distance,
53024217bd8b0cee73b9f3ea3c09c4ec.png
and
835fa07495e8d995652203b54372b60f.png
The depth of field DF − DN is
34ea225651d5a96f08f5c1a6d19cd1a1.png
For
8f09d1c59f537e790e5309b83325925a.png
, the far limit of DOF is at infinity and the DOF is infinite; of course, only objects at or beyond the near limit of DOF will be recorded with acceptable sharpness.
Substituting for H and rearranging, DOF can be expressed as
77d46a8b41790040f6615b2a62a887ee.png
Depth of field - Wikipedia, the free encyclopedia
 
http://www.thephotoforum.com/forum/...allery/182890-amateur-photo-contest-help.html

Image #1

I don't want to jack this thread any further, but I don't understand how this shallow DOF was achieved with a simple 18-55mm lens (I presume the Nikon kit lens?) at 55mm with f22.

It reminds me of the tiltshift effect that people do with Photoshop.
DOF is not a sole function of aperture. Subject distance has a lot to do with it, as does the focal length of the lens.

It's really pretty simple:
DF from the camera to the far limit of DOF are
a1015da206f3ca83e0b4013dcf1fb1d1.png
and
3dd5632cdad928d3b9c2373a4278e164.png
When the subject distance is the hyperfocal distance,
53024217bd8b0cee73b9f3ea3c09c4ec.png
and
835fa07495e8d995652203b54372b60f.png
The depth of field DF − DN is
34ea225651d5a96f08f5c1a6d19cd1a1.png
For
8f09d1c59f537e790e5309b83325925a.png
, the far limit of DOF is at infinity and the DOF is infinite; of course, only objects at or beyond the near limit of DOF will be recorded with acceptable sharpness.
Substituting for H and rearranging, DOF can be expressed as
77d46a8b41790040f6615b2a62a887ee.png
Depth of field - Wikipedia, the free encyclopedia

I don't understand all of that. What I am seeing is a depth of field I would normally associate with an extremely fast lens.

But if it is completely do-able then it is. I just don't understand it because I have never even came close to having the immediate foreground and background blur so quickly without shooting wide-open.



I will have to experiment with this then to get a better understanding.
 
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He's only asking about a technical aspect of a photo you took and how such a shallow depth of field was achieved using f/22. No need to get defensive about it.

Am I not being accused of lying?

or maybe the OP and I got off on the wrong foot... Battletone, is this what is happening? A miscommunication?
I viewed the EXIF data to see what was available and saw a $500 body (meaning the shooter probably doesn't own a $1000+ specialty lens), shooting at f22.

The only way my level of knowledge knew how to do it was with Photoshop...or with a tiltshift lens. Would that imply you would have to be lying if it wasn't natural? I suppose that would have to be inferred. But it had nothing to do with you, it was strictly about the photo and how it was obtained with the given equipment and settings.
 
55mm at f/22, probably close to minimum focusing distance, Nikon D5000 camera, no flash return detected.

What you are seeing is NOT the depth of field you would normally see from a fast lens; do you notice the clear and UNMISTAKABLE outline of a small,brightly colored sailboat or windsurfing board in the background?????

The background depth of field is not "blown out", like it would have been with a fast lens; the background is out of focus, yet the shapes are clearly,instantly recognizable. With a fast lens, like a 50mm set to f/1.8 or f/2 or even f/2.8, the background would be a mass of colors. We went over this with the leaf photo yesterday,with the same doubts being expressed about the shallow DOF capabilities of the 18-55 kit lens.

In the beach photo, the background is clearly *recognizable*. Out of focus, yes, but the shapes are recognizable. The foreground is also OOF in this shot, but the depth of field band appears to be almost a foot deep in this shot,at close range. Trust me--this shot was shot at f/22 at 55mm focal length on a D5000,and it does not look like a wide-aperture lens would render the scene if used at a wide f/stop like f/1.8 or f/2.8 or even f/3.5.

Got to this online depth of field calculator Online Depth of Field Calculator

and plug in a focusing distance of 3 feet, focal length of 55mm, use the crop-body Nikon D90, et all list, aperture of f/22...the total depth of field band is roughly 0.78 feet. Easily achievable at a close focusing distance,and one of the reasons the out of focus foreground is so apparently out of focus is that there is a tangible object that leads from the closest edge of the frame to the subject zone: instead of "air" comprising the foreground, we have solid sand as foreground,and it's a *real object *and it shows the out of focus foreground bokeh. Air shows nothing! If you wish to demonstrate this for yourself, go outside and take a picture while standing up. Focus the camera at 3 feet and shoot a picture of something simple, like a street sign pole or a lamp post at three feet away. THEN, lower the camera to virtually ground level, and include some solid foreground---grass, concrete, asphalt, whatever. Do not change the focusing distance. The second shot will show more of an out of focus effect; the reason you are being fooled and bringing up the "tilt and shift" or the so-called "miniature effect" is that this beach scene has a large amount of OOF foreground bokeh,and many shots do not have that. Our brains are conditioned to view many things a certain way, but the simple stand up and shoot, kneel down and shoot with ample OOF foreground experiment ought to be a lightbulb moment.
 
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What you are seeing is NOT the depth of field you would normally see from a fast lens; do you notice the clear and UNMISTAKABLE outline of a small,brightly colored sailboat or windsurfing board in the background?????
I misspoke...used the wrong terminology. I was referring the extremely shallow depth of the focus area. I don't know enough to pickup on how much the background should actually blur.
 
Thanks Derrel, that is a great link.
 

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