31 questions linked to/from What is one "stop"?
761 views

### Do flash guide numbers assume some amount of ambient light built-in?

My flash shows its potential range in meters, but is that indoors or outdoors? The question came up the other day when I was trying to work out whether fitting a diffusion dome would be suitable for ...
2k views

### When I change the EV compensation, how will that affect my aperture, shutter speed, or ISO?

Let say that we have the following values, as an example: Shutter speed: 1/40 Aperture: 2 ISO: 1000 How can I get the EV number for this exposure, extract (or add) an EV value (0.33, 0.66 etc.) and ...
446 views

### Why are certain apertures so popular?

Popular f stops in lenses are typically f/1.2, f/1.4, and f/1.8 for portrait lenses. The reasoning behind that is pretty self explanatory. Moving up past 1.8, I see some f/2.2 lenses occasionally, ...
3k views

### Will a prime lens help me get better portraits at a wedding?

I have a Canon 600D with the EF-S 18-55mm f/3.5-5.6 IS lens. I have a friend's wedding coming soon, and I'm not sure if my zoom lens will do a good job or not. I was thinking of buying a prime lens so ...
4k views

### How do I calculate the number of stops between two shutter speeds?

What is the math equation to calculate the difference between two different shutter speeds in stops?
489 views

### How does time of exposure relate to aperture? [duplicate]

I was trying to derive the relation between the aperture and time of exposure. I'm taking two apertures f/2 and f/4. From the formula A α 1/√t I got, f/2 α 1/√t1 -> A and f/4 α 1/√t2 ...
173 views

### I know what “stops” in an aperture are, but what are differences in stops in various light sources or areas of an image?

I understand what F-stop and T-stop mean, but I've also heard the term "stop" used like this: the background is one and a half to two stops darker than the key light What does "stop" mean in this ...
942 views

### Relationship between shutter speed and amount of light?

With all else remaining the same (ISO, aperture etc.) is there a way to compensate for changes in the lighting of the scene by changing the shutter speed of the camera such that the intensity of the ...
876 views

### Does exposure compensation affect shutter speed in aperture value mode?

When I am shooting in AV/aperture value mode, and I switch to +1 EC, will it affect my shutter speed?
111 views

### how many f stops should I allow for a given change in focal length - ISO and shutter speed remaining constant?

There are charts that show me what how many stops in shutter speed or ISO to allow when, for example, using an ND filter but given that a longer focal length reduces light available is there a chart ...
106 views

### How to shoot the sequence of adjusted exposures wanted for a ColorChecker?

I'm trying to shoot a sequence of photos needed for calibration. As instructed, I'm in manual mode, with fixed ISO 100 (camera dafault), and other values read from the lightmeter ... and now: Can you ...
10k views

### How is f-stop a measure of dynamic range?

As far as I have read f-stop is a measure of the aperture. This affects the amount of area in the foreground and background which is in focus. While having a look at the dynamic ranges of cameras I ...
436 views

### What is the formula to calculate aperture (“diaphragme” in French)?

Let's say I have these data for my camera: t : Exposure time in seconds ("temps de pose" in French) C : Incident-light meter calibration constant ("constante lumière incidente" in French) S : ISO ...