7
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How to test image quality with a camera that is focused to infinity?
This sort of testing is normally performed with an infinite conjugate optical system. One example of such is a/an (auto)collimator.
Collimators and AutoCollimators can be used interchangably for the ...
- 1,989
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Is it best to use a wide aperture when I'm focusing at infinity and depth of field is not a concern?
If I'm getting the question correctly, it is about whether at infinity focus you ought to use wider apertures like f/1.4 or narrower apertures like f/11 to get the sharpest results? The answer is, it ...
- 911
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What does focusing past infinity look like?
Past infinity sounds magical, but it's really not. Here's a thought experiment: what does something five feet away look like when you focus somewhere past that? Focusing past infinity simply means ...
- 143k
4
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What is the formula for determining where infinity focus begins?
The key to this answer is to first settle on the tolerable size of the circle of confusion. Most depth-of-field tables set this value at 1/1000 of the focal length. Kodak, for critical work set this ...
- 38.7k
3
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What does focusing past infinity look like?
Whelp... Hiroshi Sugimoto did a series focused at what he refers to as "Twice Infinity". In his notes here he states-
I set out to trace the beginnings of our age via architecture. Pushing out my ...
- 6,694
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No more turn left to get focus at infinity (hit the lens limit)
If the lens can focus on closer objects, but not achieve infinity focus, the lens needs to be brought closer to the sensor or film plane.
This often happens with adapted lenses that move the lens too ...
- 32.3k
3
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Background Focusing
If we are talking about the phase-detection autofocus (the one you get through your viewfinder), then it is important to know that the actual AF-point is larger in area than the one you can see in ...
- 6,467
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Does focusing at infinity mean the sensor is at F?
Does focusing at infinity mean the sensor is at F?
Yes. The definition of focal length is that it's the distance from the optical center of the lens to the image plane when the lens is focused at ...
- 31.7k
3
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Lens Focus Issues
The problem has nothing to do with the image not being entirely focus but more of that it is soft. At f/4.0, there is a significant softness that the lens has.
When you are looking at photo 100%, this ...
- 129
2
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Why are my long exposure sky shots out of focus?
Unlike many older manual lenses, especially primes, that have a hard stop at a lens' infinity focus setting, most autofocus lenses do not. Instead they allow for the focus mechanism to be turned past ...
- 175k
2
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Why are my long exposure sky shots out of focus?
15 second exposure with a 18mm lense with the focus cranked all the way back
When you say "cranked all the way back" it sounds like you just turned the focus ring to the far limit. That's not the ...
- 31.7k
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How do I manually focus my Nikon P520?
Yes, you can manually focus the P520. The instructions are on page 2 of the reference section in the manual, at the back. The screen shot in the manual shows an infinity symbol, so I imagine it is ...
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2
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Why are my pictures blurry even though a DOF calculator shows everything should be in focus?
Why are my pictures blurry even though a DOF calculator shows everything should be in focus?
Short answer (TL;DR): Because you're viewing them at much larger magnification than the viewing conditions ...
- 175k
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Why are my pictures blurry even though a DOF calculator shows everything should be in focus?
Understand that there is no real Depth Of Focus - only a perceived and acceptable range for it.
Physics defines that there is only a single plane at a specific distance that is in focus. In theory, ...
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Why does my Zorki 4 take blurred pics on infinity focus?
You need to adjust the infinity stops on the lens so the rear element goes closer to the image plane. Adapted lenses have this problem and most adaptors with correction elements Destroy image quality.
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How can I get infinity focus, both including the moon and a tree in the foreground?
You'll probably never get both acceptably sharp in the same exposure.
What we call Depth of Field (DoF) is just an illusion, although it is usually a very convincing one. But it breaks down with ...
- 175k
2
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What does focusing past infinity look like?
The exact nature of the image would depend on the lens and what you're pointing at.
Depth of Field effects will still come into play for the first bit past a lens's infinity point: Stuff close to the ...
- 2,315
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Is it best to use a wide aperture when I'm focusing at infinity and depth of field is not a concern?
As I understand the question, you're asking about lens sharpness/IQ when depth of field is not a concern.
Light itself is sharpest when it is not bent through an aperture restriction, but that can't ...
- 14.8k
2
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What is the formula for determining where infinity focus begins?
I think there's probably a misunderstanding of terminology here. Infinity focus is the situation where the lens is literally focused such that light from an object infinitely far away would ...
- 143k
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No more turn left to get focus at infinity (hit the lens limit)
For so-called unit focusing lenses (many but not all prime lenses are), moving it closer to the sensor is what will make it focus to infinity, and that is what the lens mechanics are actually DOING to ...
- 7,182
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Is it best to use a wide aperture when I'm focusing at infinity and depth of field is not a concern?
Is it better approach to use f1.4 for stars, city/mountains landscapes and other type of photography where object of interest are very far from me and I want to have them sharp?
It depends (stars and ...
- 6,588
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How do I find infinity focus with a kit lens when there's not enough light for optical verification?
What I've done with the 7200 is:
Set the "OK" button to 100 percent zoom. If you can see your target in Live View then refine your focus live.
If you are taking a longer exposure and cannot resolve ...
- 2,231
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What does focusing past infinity look like?
The job of the lens is to project an image of the outside world onto the surface of film or digital image sensor. It does this by handling every point of the subject (vista) individually (a point is ...
- 38.7k
1
vote
Accepted
Hyper focal distance versus maximum focus distance before infinity
Focusing distance scales and depth of field scales are holdovers from a time before many cameras had a way of viewing the scene through the lens used to take the image.
They've never been extremely ...
- 175k
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How can I get infinity focus, both including the moon and a tree in the foreground?
Another approach that you can take is to use a technque called 'focus stacking'.
In this process, you would shoot the same picture multiple times, but intentionally focusing on different areas that ...
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How can I get infinity focus, both including the moon and a tree in the foreground?
You can consult tables and charts and / or on-line computers and get the answer you want.
It is called the Hyperfocal Distance – let’s call it H.
H has this property – if a lens is focused on H then ...
- 38.7k
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Accepted
What is the point of the Olympus E-620 infinity reset
The description is quite accurate. It simply means that the camera will focus the lens at infinity each time it is powered on. Many modern lenses can focus beyond infinity and have no stops at ...
- 103k
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