Smartphone Depth of Field (DoF) With a Full Frame Camera
Jun 24, 2023 15:17:05 #
The iPhone’s crop factors are based on the size of its sensor compared to full frame. The aspect ratio for full frame is 3:2 while the iPhone sensors are normally 4:3.
Each of the iPhone cameras has a fixed focal length sated as a full frame (24x36mm) equivalent. Divide the diagonal measurement for full frame by the diagonal of the iPhone sensor to get the crop factor.
Each of the iPhone cameras has a fixed aperture. A corresponding full frame aperture can also be found by multiplying the iPhone’s aperture by the crop factor. Both physical apertures are the same.
The result is the same hyperfocal distance (HD) for both cameras. At any focus distance closer to the camera than the HD will produce almost exactly the same near and far limit and DoF although the far limits may differ depending on how close the focus distance is to HD.
Common DoF calculators do not let us set aperture settings between the common click stops. The iPhone’s cameras may have a sensor dimension that is not recognized by some of the available DoF calculators.
DoF calculators don't always calculate the Circle of Confusion (CoC) the same way. We might expect CoC to be calculated as the length of the format diagonal divided by 1500. This would lead to a CoC of 0.0288444mm for the 24x36mm full frame sensor. But the DoF calculators might use 0.025, 0.029, 0.03 or some other value. To account for differences in visual acuity the 1500 constant might (for viewing an 8x10" image from 25cm) not be the same in all calculators.
To address all of these issues we need to create a DoF calculator from scratch.
The next post contains illustrations and the spreadsheet.
Each of the iPhone cameras has a fixed focal length sated as a full frame (24x36mm) equivalent. Divide the diagonal measurement for full frame by the diagonal of the iPhone sensor to get the crop factor.
Each of the iPhone cameras has a fixed aperture. A corresponding full frame aperture can also be found by multiplying the iPhone’s aperture by the crop factor. Both physical apertures are the same.
The result is the same hyperfocal distance (HD) for both cameras. At any focus distance closer to the camera than the HD will produce almost exactly the same near and far limit and DoF although the far limits may differ depending on how close the focus distance is to HD.
Common DoF calculators do not let us set aperture settings between the common click stops. The iPhone’s cameras may have a sensor dimension that is not recognized by some of the available DoF calculators.
DoF calculators don't always calculate the Circle of Confusion (CoC) the same way. We might expect CoC to be calculated as the length of the format diagonal divided by 1500. This would lead to a CoC of 0.0288444mm for the 24x36mm full frame sensor. But the DoF calculators might use 0.025, 0.029, 0.03 or some other value. To account for differences in visual acuity the 1500 constant might (for viewing an 8x10" image from 25cm) not be the same in all calculators.
To address all of these issues we need to create a DoF calculator from scratch.
The next post contains illustrations and the spreadsheet.
Jun 24, 2023 15:25:24 #
We can replicate the DoF of the iPhone with a full frame sensor.
We can't widen the aperture on the iPhone to get a shallower DoF.
We can't widen the aperture on the iPhone to get a shallower DoF.
Jun 24, 2023 15:44:14 #
DOF is anything but simple. After a discussion here on UHH and talking with physicist friends, I have adjusted my thinking on it.
When taking photos, I use DOF preview. That tells me what I need to know. With modern cameras you can zoom in and check sharpness in different parts of the frame.
When taking photos, I use DOF preview. That tells me what I need to know. With modern cameras you can zoom in and check sharpness in different parts of the frame.
Jun 24, 2023 16:46:54 #
JD750 wrote:
DOF is anything but simple. After a discussion here on UHH and talking with physicist friends, I have adjusted my thinking on it.
When taking photos, I use DOF preview. That tells me what I need to know. With modern cameras you can zoom in and check sharpness in different parts of the frame.
When taking photos, I use DOF preview. That tells me what I need to know. With modern cameras you can zoom in and check sharpness in different parts of the frame.
You are waaaaaay too realistic for UHH. Selmsie, OTOH, is true to the UHH Sacred Tradition of geek trolling. You could learn a lot from him ... acoarst nothing actually photographically useful but churning your grey matter is good exercise. Have you checked out his "scientific" website ?
More novice geeks will join the thread to nit pick his presentation and Ill hafta pop lots more corn and melt lots more butter.
He makes coffee shoot outa my nose !
(Download)
Science inexorably trudges forward.
(Download)
It dont mean a thing if it aint got that swing ... do woppa do wop do wop do.
(Download)
Jun 24, 2023 16:57:18 #
User ID wrote:
You are waaaaaay too realistic for UHH. Selmsie, OTOH, is true to the UHH Sacred Tradition of geek trolling. You could learn a lot from him ... acoarst nothing actually photographically useful but churning your grey matter is good exercise. Have you checked out his "scientific" website ?
As the king of all trolls you could not wait to defecate on this thread as you do on so many others.
Too bad you have nothing intelligent or positive to contribute.
Jun 24, 2023 16:59:45 #
selmslie wrote:
As the king of all trolls you could not wait to defecate on this thread as you do on so many others.
Too bad you have nothing intelligent or positive to contribute.
Too bad you have nothing intelligent or positive to contribute.
Jun 24, 2023 17:47:28 #
User ID wrote:
I'm ROTFLMAO but churning the area matter couldn't hurt. No I have not checked out the scientific site however I have checked out the links to his photos.You are waaaaaay too realistic for UHH. Selmsie, OTOH, is true to the UHH Sacred Tradition of geek trolling. You could learn a lot from him ... acoarst nothing actually photographically useful but churning your grey matter is good exercise. Have you checked out his "scientific" website ?
Jun 24, 2023 18:46:17 #
JD750 wrote:
I'm ROTFLMAO but churning the area matter couldn't hurt. No I have not checked out the scientific site however I have checked out the links to his photos.
NUFF SED !!!
Jun 24, 2023 19:17:19 #
JD750 wrote:
DOF is anything but simple. After a discussion here on UHH and talking with physicist friends, I have adjusted my thinking on it.
When taking photos, I use DOF preview. That tells me what I need to know. With modern cameras you can zoom in and check sharpness in different parts of the frame.
When taking photos, I use DOF preview. That tells me what I need to know. With modern cameras you can zoom in and check sharpness in different parts of the frame.
DoF is seldom a priority for anyone. The concept really doesn't require a deep understanding of the science behind it.
Anyone who wants a lot of DoF can benefit from small sensor.
Capturing a shallow DoF like flowers calls for a larger sensor, a longer focal length and a wide aperture.
If you want to photograph wildlife or portraits you might fall somewhere in between those extremes.
The science is academic and challenging for anyone who doesn't understand what is happening.
But knowledge is power.
Jun 25, 2023 12:34:43 #
User ID wrote:
You are waaaaaay too realistic for UHH. Selmsie, OTOH, is true to the UHH Sacred Tradition of geek trolling. You could learn a lot from him ... acoarst nothing actually photographically useful but churning your grey matter is good exercise. Have you checked out his "scientific" website ?
I dunno. I was just thinking that UHH had gotten a bit thin and lacking in technical discussions recently, so personally, glad to see something more interesting than “what lens should I take to Mongolia?” (Which happens at least daily).
Jun 25, 2023 13:48:26 #
TriX wrote:
I dunno. I was just thinking that UHH had gotten a bit thin and lacking in technical discussions recently, so personally, glad to see something more interesting than “what lens should I take to Mongolia?” (Which happens at least daily).
Many here on UHH would rather not comment.
"Better to remain silent and be thought a fool than to speak and to remove all doubt." — Abraham Lincoln
Here is the PDF: Smartphone Depth of Field (DoF) With a Full Frame Camera
I hope it clarifies the concept for a some. I learned something myself.
Jun 25, 2023 15:25:36 #
Jun 25, 2023 16:06:56 #
selmslie wrote:
DoF is seldom a priority for anyone.
Why do you say this? DOF is a significant factor in any photograph.
Jun 25, 2023 17:41:39 #
selmslie wrote:
DoF is seldom a priority for anyone.
Grahame wrote:
Oh
JD750 wrote:
Why do you say this? DOF is a significant factor in any photograph.
Selecting the subject, the camera, the lens and focal length, composing the scene, holding the camera steady, focusing - these are priorities.
The right exposure via the right combination of ISO, shutter speed and aperture - these are also priorities.
How many times have you gotten this far and then wondered whether the DoF was going to be OK? Did you take out your DoF calculator to double check it? If not then DoF was not a priority relative to the above factors.
If DoF were a priority you wouldn't use a cell phone because you can't adjust the aperture. You are stuck with the DoF that results from the subject distance.
Jun 25, 2023 18:10:28 #
selmslie wrote:
Did you take out your DoF calculator to double check it? If not then DoF was not a priority relative to the above factors.
That statement has to win 1st prize. I'll leave you guessing what the competition was.
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