The f-stop of an optical system expresses the diameter of the entrance pupil in terms of the focal length of the lens; in simpler terms, the f-stop is the focal length divided by the "effective" aperture diameter. It is a dimensionless number that is a quantitative measure of lens speed, an ...
38
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2answers
12k views
What does f-stop mean?
What does f-stop mean? Is it the same thing when people say "2 stops" for example?
17
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4answers
2k views
How do you find out the “sweet spot” of a lens?
I've tried googling this, but have never found a satisfactory answer.
I've heard the term "sweet spot" thrown around by some photographers to mean the f-stop of a lens which results in the highest ...
18
votes
4answers
2k views
Why do compact digital cameras not have the aperture range of DSLRs?
Why is it that on compact digital cameras the aperture never seems to go any smaller than about F8 ? Even on high-end compacts such as the Cannon G10 or Panasonic LX5. Is there some practical or ...
10
votes
5answers
2k views
What does the f-stop printed on the lens refer to?
I have read this,so I know what an f-stop is, but what does the number on printed the lens signify?
Is this is the maximum f-stop, the ideal, or something else?
11
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5answers
912 views
How can aperture be f/11 on a lens with an aperture range designation of 3.5-5.5?
I made a series of outdoor shots with Nikon D5000, with the 18-55mm 1:3.5-5.6G VR kit lens.
On some shots, I see in the EXIF info f/11, and in another shot, f/9.
How can that be, that the f-number ...
17
votes
6answers
3k views
How many stops can a digital camera capture?
How many stops can a digital camera capture?
I wondering if some one know, or have measure, the stops also for the negative or positive film, the human eyes, the monitor, the television, etc...
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13
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2answers
1k views
12
votes
6answers
524 views
Why are only certain shutter speeds or apertures available?
For the exposure control function DSLRs there are specific shutter speeds available. For example there are 1/4, 1/100, 1/500. Why, even in high end DSLRs, is there no option to use a custom shutter ...
10
votes
2answers
473 views
How to stop a high F number from appearing blurry?
I have been out taking some evening photos (just after sunset) and I have noticed that in a number of instances the higher f numbers ( 14+ ) are appearing more blurred than the lower f numbers ( < ...
3
votes
2answers
108 views
What's the difference between real and effective aperture?
I understand that the simple idea that f-stop is focal length divided by aperture really applies to a simple single-glass lens, not the compound lens systems used to provide good image quality in ...
3
votes
3answers
518 views
Choosing first lens for Nikon D-90 body
I'm looking to get a prime lens to go with the Nikon D-90 body. I'm looking at 50mm or 35mm and f/1.8 or f/1.4 and AF or AF-S. It appears that VR (Vibration Reduction) is not an option for any of ...
5
votes
2answers
450 views
What does “N stops” mean when describing an image stabilizer?
If you ever purchased any lens with IS then you have heard this term like "3 Stop Stabilization" or "4 Stop Stabilization". Now, I am familiar with this Stop for ISO and Aperture. But this I don't ...
