How can it be?

Darkroomguy

Darkroomguy

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How is it an iPhone 14, set to ultrawide, has infinite depth of focus...... touching the lens to infinity? I bought a Rokinon 14mm for my Nikon D-Series bodies. Even at f/22 I'm no where near that range of depth of field. I need/want far more for "Forced Perspective".

DarkRoomGuy
 

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Setting aside the likely 'computational' photography aspect of the iPhone 14, it has a tiny sensor and it is a characteristic that the smaller the sensor the greater the DoF (Depth of Field).

Therefore, you are never likely to see such a DoF you are seeing from your iPhone whilst using a dSLR or Mirrorless body.
 
As implied already the ultra wide may be around 13/14mm equivalent but the actual focal length will be lesss than 4mm — I don’t know the actual sensor sizes of the various iPhone cameras but the 28mm equivalent ones are around 4mm. Good luck with finding a 3mm lens for your Nikon ;)
 
Sensor on the pro version is 1/2.55 (5.6x4.2mm) with about a 6.2x crop factor.

Need to get a 2mm lens to get equivalent depth of field.

If you play with focus stacking then I would have thought a DSLR will give you much more options than an iphone.
 
Box Brownie said:
it has a tiny sensor and it is a characteristic that the smaller the sensor the greater the DoF (Depth of Field).

Therefore, you are never likely to see such a DoF you are seeing from your iPhone whilst using a dSLR or Mirrorless body.
Click to expand...


exactly this...... :plus1:
 
Darkroomguy said:
Even at f/22 I'm no where near that range of depth of field.
Click to expand...
Yes you are.

A quick SWAG:
With your APS bodies (D5300) a 14mm set to f/16 has a hyperfocal distance (HFD) of ~ 2ft (14% of 14; focal length as a percentage of itself). And when focused at 2ft the DOF extends from 1 ft to infinity. At f/32 the HFD reduces to ~ 1 ft (2 stops is a factor of 2), and at f/22 it would be about half way between them (1.5 ft). Whenever a lens is focused at the HFD the DOF extends from halfway to the focus point out to infinity; so at f/22 the DOF is ~ 9" to infinity.

Because it's a SWAG, and because accurately judging focus distance is problematic, there is a little error; so focus a little longer than the estimate. If you focus short of the HFD you lose a lot of DOF. But no matter how far beyond the HFD you focus, the far DOF limit is always infinity; and the near limit will never be less than the HFD itself.

Now, the DOF calculation is based upon the standard for acceptable sharpness in a viewed image; it is nowhere near pixel level sharpness. And diffraction is working against you in recording small details at distance... at f/22 the minimum apparent size of a detail that can be recorded is ~.03mm; and the max recorded resolution on an an APS sensor is ~ 3MP (still enough for use online at 2MP).
 
Darkroomguy said:
How is it an iPhone 14, set to ultrawide, has infinite depth of focus...... touching the lens to infinity? I bought a Rokinon 14mm for my Nikon D-Series bodies. Even at f/22 I'm no where near that range of depth of field. I need/want far more for "Forced Perspective".

DarkRoomGuy
Click to expand...
Just a quick point - don't confuse depth of focus with depth of field, they are entirely separate and, although there will be massive depth of field with your phone camera, the depth of focus will hardly exist at all. What you're talking about is depth of field.

What others have said is right, it's all or mainly down to the tiny sensor size, but possibly also down to the very clever software - I believe that some phone cameras do a type of focus stacking and combine the images. Sensor sizes can be confusing, especially when tiny sensors are involved. This confusion probably arises because some manufacturers quote, not the actual size used in digital cameras, but an imperial fraction that originates back to the Vidicon tubes used in TV sets 70 years ago. There doesn’t seem to be any meaningful correlation between the quoted and the actual size, and if I was a cynic I might think that the manufacturers who quote their sensor sizes in this way might be trying to mislead their customers.
This may help https://www.dpreview.com/articles/6110937480
 
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