Camera properties

1. Features of the active camera

In this area you will find the characteristics of the active camera, namely:

  • Sensor size

  • The Crop factor

  • The value of the circle of confusion

  • Image size in pixel

  • ISO range

  • The speed range

  • The number of stops the camera stabilization system compensates

  • Display of actual focal length or 35mm equivalent

  • The steps for the ranges: ISO, shutter speed and aperture

You have the possibility to edit certain characteristics by clicking on the pencil icon or to delete a model added by you by clicking on the trash can icon.

2. Global camera settings

In this area you will find the settings that will apply to all cameras, namely:

  • The presence or not of a focal length multiplier/reducer and its value

A focal length multiplier is an accessory that is inserted between the lens and the body and which allows to obtain the framing that would be obtained with a lens with a focal length longer than the one used. It is an economical solution that allows you to equip yourself more lightly.On the other hand, by multiplying the dimensions of the central part of the image, its surface area is squared and its luminosity is divided in the same proportions.Example:
  • With a multiplier by 1.4 the brightness is still divided by 2. We therefore lose 1 diaphragm.
  • With a focal doubler, the brightness is divided by 4. We therefore lose 2 diaphragms.
  • With a triplifier of focal length, the luminosity is divided by 9. We therefore lose more than 3 diaphragms.
Another consequence concerns autofocus. If we double the focal length of a lens open at f / 2.8, we obtain another lens but open at f / 5.6, which is the maximum limit for most autofocus.If you have such an accessory, you only need to enter the value of its multiplier. You can activate it or not with the On / Off button.

  • If the shutter speed unit is always displayed in s (90 s -> 1 min 30 s)

3. Management of favorites (only with the Pro version)

It is possible to define cameras as favorite (no limit on the number) to facilitate switching from one to another when you have several cameras.

Adding a camera to favorites is done by choosing the desired camera then clicking on the heart-shaped icon (turns red).

The selection of a camera in the favorites is done simply by clicking on it.

To remove a camera from favorites, just click on the heart-shaped icon (turns gray).

4. Camera repository

Selecting a camera from the repository is simply done by clicking on it or by performing a search (magnifying glass icon). The selected camera becomes the active camera for the various tools.

If your camera is not in the list, don't panic, you can add it yourself by clicking on the plus icon, then entering its characteristics.

If you do not know the characteristics of your camera, you can find them on the site: Digital camera database

Camera change shortcut (only with Pro version)

At the bottom of each screen, you can access the choice of cameras by clicking on the camera icon.

Add / Edit Camera

Adding a camera is done by clicking on the plus icon and changing the active camera by clicking on the pencil icon.

If the camera is part of the application library (was not created by the user), it will not be possible to change the company name and the model name.

It's possible to capture a film camera by setting the "Digital camera" selector to Off. In this case, the size of the sensor and the resolution will not have to be entered.

You must enter the characteristics of your camera, namely:

  • Sensor size (Width x Height)

  • Image size (Width x Height) in pixel

  • ISO range

  • Speed range

To save them, just click on the floppy disk (top right).

And voila, the camera is now available!

Circle of confusion

The circle of confusion is a term that one discovers with the depth of field. It is a physiological reality (visual acuity) that makes it possible to express the impression of sharpness of a photograph.

In photography, the rays which pass through the lens from a tiny point on the plane of sharpness do not converge towards an ideal single point, but form a more or less great spot, for the optics are not perfect and the focus may be more or less accurate. These spots are called circles of confusion, for when they become too blurred, two juxtaposed points seem to merge.

The circle of confusion represents the minimum blur diameter at the sensor to be visible to the naked eye. From this value the details seem mixed, they are confused.

The circle of confusion, applied to a sensor, is the smallest detail that it is able to grasp for a given opening, knowing that the sensor is composed of photosites of well-defined size that a moire filter as well as a reconstruction colors (demosaicing) will artificially expand this smallest detail. We are not interested here in the consequences of viewing on a screen or on a paper print that would involve the size of the screen or print and the distance between the image and the observer (and its possible visual acuity failure or no).

The size of the circle of confusion is calculated simply by dividing the diagonal of the sensor by a constant:

  • 1440 uses a less severe criterion, it is the constant most often used

  • 1730 is the constant that most closely matches the physiological reality

  • 3000 uses a more severe criterion

The Airy disk (only with the Pro version)

For a given opening, a point source of light will spread over the sensor in a disk called Airy disk whose diameter is proportional to the opening of the lens. Impossible to see a finer detail, physics forbids it. Then, this stain is spread slightly by the moire filter and demosaicing. In the end, the smallest diameter visible on the sensor is equal to the diameter of the Airy disk increased by about a pixel width. Following this reasoning, we see that we don't at any time intervene the size of the sensor, but only the size of its photosites.

Custom value (only with Pro version)

By clicking on the pencil and eye icon, you can set a custom value for the circle of confusion.

Increments

Here, we define the normalised exposure scales corresponding to the settings of the box that will be used in the other menus.

For each of the 3 exposure parameters (sensitivity, exposure time and aperture), there is a scale of normalised values. Moving from a standard value to the next or previous one is equivalent to changing the exposure index by 1 (+1 or -1 EV). In other words, multiply or halve the amount of light (exposure time and aperture) or sensor sensitivity (sensitivity).

Sensitivity

Sensor sensitivity is expressed in ISO (International Standard Organization).

If the sensitivity of the sensor is doubled, the same exposure will require half the light (ISO 400 is twice as sensitive as ISO 200, which is twice as sensitive as ISO 100).

Conversely, whenever the sensitivity of the sensor is reduced by half, obtaining the same exposure requires a contribution of twice as much light.

Standard sensitivities (in ISO):

50 – 100 – 200 – 400 – 800 – 1,600 – 3,200 – 6,400 – 12,800 – 25,600 – 51,200 – 102,400

Going to the right, we increase the sensitivity, it is as if we added IL. Indeed, if we amplify the sensitivity without moving the aperture and the exposure time, this is equivalent to overexposing the photo. We get the same result as if we had doubled the amount of light.

Examples:

  • Change from 100 to 200 ISO: + 1 EV

  • Move from 100 to 400 ISO: + 2 EV

  • Change from 800 to 400 ISO: - 1 EV

Exposure time

The exposure time (also called shutter speed) is the duration (expressed in seconds or fractions of seconds) during which the shutter is open to allow light to pass through the sensor.

Standardised shutter speeds (or exposure time in seconds):

30 s – 15 s – 8 s – 4 s – 2 s – 1 s – 1/2 s – 1/4 s – 1/8 s – 1/15 s – 1/30 s – 1/60 s – 1/125 s – 1/250 s – 1/500 s – 1/1000 s – 1/2000 s – 1/4000 s – 1/8000 s

The longer the duration (slower speed), the more light will pass. Moving from one standard value to another is equivalent to twice as much light (to the left) or twice as much light (to the right).

Examples:

  • Change from 1 s to 2 s: + 1 EV

  • Change from 1/15 s to 1/30 s: -1 EV

  • Change from 1/500 s to 1/125 s: + 2 EV

Aperture

Thanks to the diaphragm of the lens, the diameter of the aperture through which the light passes can vary. Depending on its size, this aperture will allow more or less light to pass for the same period of time.

Normalised relative apertures:

1.0 – 1.4 – 2.0 – 2.8 – 4.0 – 5.6 – 8.0 – 11.0 – 16.0 – 22.0 – 32.0 – 45.0 – 64.0 – 90.0 – 128.0

A large diaphragm aperture corresponds to a small digit (4, 2.8, 1.4, ...) and a small aperture is represented by a large digit (11.0, 16.0, 22.0, ...).

The aperture is generally marked "f /" or "f:" or, for example, for an aperture of 4: f / 4 or f: 4.

Going left, we add EV: The larger the aperture (small number), the greater the amount of light reaching the sensor. As with the exposure time, switching from one standard value to another is equivalent to twice as much light (to the left) or twice less light (to the right).

Examples:

  • Change from f / 4 to f / 2.8: + 1 EV

  • Change from f / 8 to f / 4: +2 EV

  • Change from f / 8 to f / 11: - 1 EV

In summary, it is possible to increase the exposure index by + 1 EV:

  • By multiplying the laying time by two (for example from 1 to 2 seconds, from 1/500 s to 1/250 s, ...),

  • By increasing the aperture of the diaphragm by a value, i.e. By choosing a smaller digit (e.g. from f / 5.6 to f / 4),

  • By doubling the sensitivity (for example from 100 to 200 ISO).

And conversely, -1 EV is equivalent to dividing the exposure time or the sensitivity by two or to decrease by a standard value the opening of the diaphragm (move to a higher figure).

The adjustment increments

Attention, on the devices, it is rare that the settings are made by the whole value of EV. Usually, when you turn a control dial up or down, it changes the setting of 1/2 or 1/3 of EV.

The adjustment steps may differ from one exposure parameter to another (speed, aperture, sensitivity), from one device to another and even from one user to another for the same device (The increment can be customised).

Examples of intermediate values

By adjusting your device, you will therefore find the normalised values ​​presented in the previous part, but also intermediate values.

Examples of apertures between f/2.8 and f/22.

• 1 EV adjustment:

2.8 – 4.0 – 5.6 – 8.0 – 11.0 – 16.0 – 22.0

• 1/2 EV adjustment:

2.8 – 3.5 – 4.0 – 4.5 – 5.6 – 6.7 – 8.0 – 9.5 – 11.0 – 13.0 – 16.0 – 19.0 – 22.0

• 1/3 EV adjustment:

2.8 – 3.2 – 3.5 – 4.0 – 4.5 – 5.0 – 5.6 – 6.3 – 7.1 – 8.0 – 9.0 – 10.0 – 11.0 – 13.0 – 14.0 – 16.0 – 18.0 – 20.0 – 22.0

• 1/10 EV adjustment:

2.8 - 2.9 - 3.0 - 3.1 - 3.3 - 3.4 - 3.5 - 3.6 - 3.7 - 3.9 - 4.0 - 4.1 - 4.3 - 4.4 - 4.6 - 4.8 - 4.9 - 5.1 - 5.3 - 5.5 - 5.6 - 5.9 - 6.1 - 6.3 - 6.5 - 6.7 - 7.0 - 7.2 - 7.5 - 7.7 - 8.0 - 8.3 - 8.6 - 8.9 - 9.2 - 9.5 - 9.9 - 10.2 - 10.6 - 11.0 - 11.3 - 11.7 - 12.1 - 12.6 - 13.0 - 13.5 - 13.9 - 14.4 - 14.9 - 15.5 - 16.0 - 16.6 - 17.1 - 17.8 - 18.4 - 19.0 - 19.7 - 20.4 - 21.1 - 22.0

Examples of shutter speeds between 1 s and 1/250 s.

• 1 EV adjustment:

1 s – 1/2 s – 1/4 s – 1/8 s – 1/15 s – 1/30 s – 1/60 s – 1/125 s – 1/250 s

• 1/2 EV adjustment:

1 s – 0.7 s – 1/2 s – 0.3 s – 1/4 s – 1/6 s – 1/8 s – 1/10 s – 1/15 s – 1/20 s – 1/30 s – 1/45 s – 1/60 s – 1/90 s – 1/125 s – 1/180 s – 1/250 s

• 1/3 EV adjustment:

1 s – 0.8 s – 0.6 s – 1/2 s – 0.4 s – 0.3 s – 1/4 s – 1/5 s – 1/6 s – 1/8 s – 1/10 s – 1/13 s – 1/15 s – 1/20 s – 1/25 s – 1/30 s – 1/40 s – 1/50 s – 1/60 s – 1/80 s – 1/100 s – 1/125 s – 1/160 s – 1/200 s – 1/250 s

Focal values

Used to define whether the focal length value that will be entered in the different tools is the real value or the 35 mm equivalence.

Stabilization stops

Stop value that the case stabilization system compensates. This value is used for calculating the speed limit for handheld shots (without a tripod).