Beginner circle of confusion

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sifeziwe
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good day everyone, new to the forum, still a novice. i would like to know how the concept of the circle of confusion work, thank you for your response
 
Welcome to Talk Photography, we seem to have picked up a number of new members with technical questions, is this your photography course homework?
 
It's a rather confusing topic.
The circle of confusion is related to how far apart two points have to be before the average person can tell there are two and not just one that combines both. It is dependant on the final print size, viewing distance & the degree of magnification. IIRC It is usual to assume the final output is a 10x8" print viewed at arms length.
If you imagine a long straight road at night, when a car is coming the other way it's lights will start off just looking like a single point, as you get closer your eyes will at some point be able to tell there are two headlights. this is a similar factor.
 
Hi Sifeziwe, And welcome aboard TP. "Enjoy"
 
It exists but not something most photographers even consider when taking photographs. It’s a term used widely to sell you apps that are generally not required.

so this will never affect my shots in any way ?
 
It's a rather confusing topic.
The circle of confusion is related to how far apart two points have to be before the average person can tell there are two and not just one that combines both. It is dependant on the final print size, viewing distance & the degree of magnification. IIRC It is usual to assume the final output is a 10x8" print viewed at arms length.
If you imagine a long straight road at night, when a car is coming the other way it's lights will start off just looking like a single point, as you get closer your eyes will at some point be able to tell there are two headlights. this is a similar factor.

that makes total sense, when two points are further away from each other, will have a single point until they approach your direction
 
that makes total sense, when two points are further away from each other, will have a single point until they approach your direction
In the same way magnifying the image would make points you can't tell apart big enough you can tell them apart.
From the point of depth of field an image looks acceptably sharp as long as the blur is less than the size you can tell apart (circle of confusion). In reality a lens will only focus items at a specific distance, while for a range of distances either side it's focus well enough the human eye can't spot the blur. Determining how blurred an image can be yet look sharp is what the circle of confusion is all about.
 
Welcome to the forum and enjoy your self here :wave:
 
In the same way magnifying the image would make points you can't tell apart big enough you can tell them apart.
From the point of depth of field an image looks acceptably sharp as long as the blur is less than the size you can tell apart (circle of confusion). In reality a lens will only focus items at a specific distance, while for a range of distances either side it's focus well enough the human eye can't spot the blur. Determining how blurred an image can be yet look sharp is what the circle of confusion is all about.

now I get it, was a bit confused now am sorted, thank you.
 
Normally the term 'circle of confusion' refers to the orbit of the hand on returning home when in drink and whilst attempting to get the key into the lock. Generally, the greater quantity of units having been consumed, then the greater is the diameter of the circle.
 
good day everyone, new to the forum, still a novice. i would like to know how the concept of the circle of confusion work, thank you for your response


In optics, a circle of confusion is an optical spot caused by a cone of light rays from a lens not coming to a perfect focus when imaging a point source. It is also known as disk of confusion, circle of indistinctness, blur circle, or blur spot.

In photography, the circle of confusion (CoC) is used to determine the depth of field, the part of an image that is acceptably sharp. A standard value of CoC is often associated with each image format, but the most appropriate value depends on visual acuity, viewing conditions, and the amount of enlargement. Usages in context include maximum permissible circle of confusion, circle of confusion diameter limit, and the circle of confusion criterion.

Real lenses do not focus all rays perfectly, so that even at best focus, a point is imaged as a spot rather than a point. The smallest such spot that a lens can produce is often referred to as the circle of least confusion.

Les :)
 
maybe I can offer you and all your friends who have signed up to this forum a little bit of advice...

if you sign up, and your first post is a single sentance question asking "what is...." - you're going to get a few of the members pushing back or saying "just do your own homework/google it".

However, if you go into the beginners forum, introduce yourself, give a quick "biography" or details of what you do, what you like shooting, what you feel you'd like to learn from being here, and how you think you could maybe help others on here" then you'll get a far more welcoming response.

If you then proceed to share some of your photo's in one of the photo sharing sections that'd be brilliant. Same thing if you apply your knowledge of photography to giving critique and feedback on other peoples images,

What I'm saying here, is that this is a community, not just a reference library staffed by people for your assitance. Join, participate, give something to the community, and it'll be reciprocated many, many times over.

Don't be offended if people post links to various websites in answer to a question, very often these posted links ARE the best resource that the person knows to explain it - it's a "curated" link if you will. I've posted many links to your college compatriots questions already - because, frankly, the best info I know was in them, and not only was I not going to plagiarise the other site, I wasn't about to re-type 5000+ words and source multiple photos and diagrams in illustration.

You may notice a marker against my name stating that I'm a Staff Member here. As such, what i've stated above would probably be a good thing to take on board, and to pass onto your friends who may also be posting on here - and perhaps also feed back to the lecturer who pointed you at this forum in the first place...

Enjoy your time within our community :)
 
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