# Questions tagged [circle-of-confusion]

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### Airy disks and pixel pitch on circle of confusions?

I read in this paper by Toshiba, which is in regards to optics in machine vision, that In machine vision, which processes each pixel of an image sensor at high brightness levels, the permissible ...
• 133
710 views

### Is this diagram I've drawn in regards to Depth of field correct?

This diagram is modelled after a video I saw on depth of field formula and its derivation. I have now learnt a bit more regarding Depth of focus and how it refers to "the tolerance of placement ...
• 133
115 views

### Why is depth of field not always symmetrical about the object, yet depth of focus is practically symmetrical?

I have found an explanation on this, however I cannot seem to picture what the explanation is saying. From a Toshiba technical article: Remember that the previous subsection mentioned that the depth ...
• 133
2k views

### If focal length does not affect DOF, why doesn't a 25mm lens at an f-stop of 4 give me the same DOF as a 100mm on an f-stop of 16?

After having spent some time reading about DOF and the derivation of its formula, I tried calculating the theoretical DOF of different lenses. Now to my knowledge, a camera using a lens with a focal ...
• 133
84 views

### How much is the depth of field of Weegee's "f/8 and be there"?

I am curious about the depth of field of the famous saying "f/8 and be there". "f/8 and be there" is often associated with hyperfocal distance on 35mm, which means infinite depth ...
• 105
1 vote
358 views

### What is the "d/1500" circle of confusion formula for 35mm-format based on?

I get the concept behind CoC, I'm just trying to wrap my head around the formula. I've seen the simple approach ("d/1500"), and I've read that "1500" is based on a standard print ...
• 77
1 vote
486 views

### Circle of confusion for viewing images on a smartphone

I'm shooting images on my DSLR and wondering what the circle of confusion would be if it were to be viewed only on an iPhone. As I understand it, the CoC formula can be expressed as: (Acuity * Viewing ...
• 77
1 vote
890 views

### Calculating the "35mm equivalent" circle of confusion/DoF

I'm gonna introduce my concrete example, but I'd like to know how do do this calculation in general. Say I have a middle-format camera with film height 58mm and a 90mm/3.5 lens. What is the equivalent ...
• 113
1 vote
83 views

### Convex lens, object distance, distance, focal length, in what state is the hyperfocal state? [closed]

Suppose we have a convex lens for a middle school physics experiment, a screen, and an object being imaged, under what state will we find the hyperfocal state? The screen is the imaged screen. It can ...
• 155
543 views

### What is the acceptable CoC (Circle of Confusion) of the human eye to directly observe the object? [closed]

What is the acceptable CoC (Circle of Confusion) of the human eye to directly observe the object? The human eye has many cells and high pixels. Should the permissible circle of confusion be small?
• 155
747 views

### How do I specify circle of confusion and depth of focus in practice?

This question is related to this one; I am asking a very similar one because I didn't see in the answers how to arrive to a numeric answer in practice. Suppose I'm going to shoot a portrait and have ...
• 339
1 vote
2k views

### What are appropriate Circle of Confusion values for high-megapixel cameras? [duplicate]

Since the film days we have used 0.03 CoC for determining depth of field and similar calculations. In digital terms, does this best match with 6 or 12 or 24 or 36Mpixel full frame sensors? If this ...
• 19
242 views

### Why do viewing conditions affect Depth of Field?

There's a lot of information here and elsewhere about how things such as aperture, focal length, and subject/focus distance affect Depth of Field (DoF). Most people seem to understand that side of it ...
• 175k
4k views

### How do depth of field and the circle of confusion relate to pixel size on the sensor?

I have been reading about depth-of-field and presume to have a sufficient understanding of what it means and how it is related to lens properties, lens aperture, focal length, sensor format size and ...
633 views

### For digital sensors and in terms of imaging medium, is the minimum CoC equal to the size of 1 sensor pixel or 2? And why?

For digital sensors and in terms of imaging medium, is the minimum CoC equal to the size of 1 sensor pixel or 2? And why? For example purposes using a 35mm Full Frame digital sensor where the pixel ...
• 449
1k views

### Why do some people say to use 0.007 mm (approximate pixel size) for the CoC on a Canon 5DM2?

The 5DM2 pixel size is approximate 0.00645mm in size and so some people talk about using 0.007mm as the CoC. I think canon said once they use 0.035mm for DOF charts, full frame normal is 0.033mm, ...
• 449