Theory- The Camera
Theory The Camera
Shutter Speed
What is shutter speed? It is the length of time in which the shutter of the camera is open. To understand this, we need to know how the shutter works and where the shutter is located on the camera. The shutter on a DSLR is located inside the camera covering the image sensor. The shutter is made up of 5-15 blades that are controlled either by spring action or electronically by opening and closing depending on your camera settings. The smaller the hole or shutter the less light that gets in.
Focal Plane Shutter
The focal-plane shutter consists of two light-tight fabric blinds or a combination of metal blinds moving in time across the film immediately in front of the image plane. Usually found in film cameras. The first blind uncovers the film, and the second blind covers it up again, the two blinds forming a traveling slit the width of which determines the exposure time: the narrower the slit, the shorter the time. The actual travel time is constant for all exposure times.
Exposure Control
In Photography, the exposure triangle is defined by the relationship between shutter speed, ISO and aperture. Not always in that order depending on your creative techniques. This theory stands for both DSLR cameras, mirrorless and film. Basic understanding of this triangle will help how an image will look before during and after you take it. This basic knowledge will make for a better photographer. Wouldn't the world be great if we could just point and shoot? Well, we can but in manual mode we are required to use this knowledge to be creative, when have full control. https://www.polarprofilters.com/blogs/polarpro/the-three-elements-of-the-exposure-triangle
Flash Synch Speed
This is the fasted shutter you can use along with the flash. It is measured by how fast your synch speed can match your flash when using a camera with a focal plane shutter. Modern cameras will usually have sperate shutter blades that go across the sensor exposing it to the light. Too much from the short blast of flash can have a detrimental effect on the camera sensor if only for a moment. The movement of both bladed working together will create a small opening, if shooting at too high a shutter speeds the shutter will partially block the light creating a unusable image with dark bands across the middle. https://www.imaginated.com/blog/what-is-flash-sync-speed/
My Examples
Shutter Speed
All my images are of the same item taken with a Canon 2000d using a 18-300mm lens but taken at different settings.These images were taken in Manual, Raw, Adobe RBG and edited as required using Camera raw basic. My camera setting whereas shown below for each image. These images show a sparkler taken at different shutter speeds. You can clearly see the Faster the shutter speeds the more in focus the image. Fast shutter speeds are usually used to capture fast moving images to achieve a clean image. Effectively allowing you to ‘stop time’. Fast shutter can also be used in high light environment to control the light that is allowed in. The shorter the period the shutter is open the less light is allowed in. Slower shutter speeds are used for low light situations as they are longer the shutter is open the lighter is allowed in. A Slower shutter is also used to capture movement and to induce blur and added effect. The opposite of the fast shutter speed.
0’’4-f11-100
Aperture
Aperture can be defined as the opening in a lens through which light passes to enter the camera. It is an easy concept to understand if you just think about how your eyes work. As you move between bright and dark environments, the iris in your eyes either expands or shrinks, controlling the size of your pupil.
Reciprocity
Reciprocity is the law between shutter and aperture. It stipulates that one stop increase in aperture is equivalent to the shutter duration should double. Both increase light by one stop. The photographer can also overexpose or underexpose. Understanding reciprocity allows them to do this in a controlled environment. Image brightness is determined by the amount of light that contacts the sensor. This is controlled by the duration of the exposure (the shutter speed), the intensity of the light (aperture), and the sensitivity of the sensor or film (ISO). https://www.picturecorrect.com/understanding-reciprocity-in-photography/
Transmision of light
Direct transmission of light is where light passes through a material in one direction direction. Diffuse transmission is different—the light gets scattered in unpredictable directions as it passes through materials like paper, etched glass, white acrylic, and thin white fabric. Langfords basic Photography
Optimum lens quality
Image quality is affected by the size of the aperture of the lens. Variations in picture quality at different apertures are usually barely noticeable, but they are there. Different lenses have different aperture ranges depending on whether they are fixed, focus free or telephonic.
My Examples
Creative effect
All my images are of the same item taken with a Canon 2000d using a 18-300mm lens but taken at different settings. These images were taken in Manual, Raw, Adobe RBG and edited as required using Camera raw basic. My camera setting whereas shown below for each image. Tes images show an autumn leaf taken at different apertures. You can clearly see the difference the f stop has on the depth of field. The effect of aperture is depth of field. Depth of field is the amount of your photograph that appears sharp from front to back. Some images have shallow depth of field, where the background is completely out of focus (Image 1). Other images have a high depth of field, where both the foreground and background are sharp(image 3)
1/200-f5-100
1/40-f16-100
1/25-f22-100
Focal length
The focal length of a lens is determined when the lens is focused at infinity. Lens focal length tells us the angle of view and how much of the scene will be captured in the image. The longer the focal length, the narrower the angle of view and the higher the magnification. This will all depend on the type of lens being used.
Understanding focal length is key to understanding how most cameras work. The focal length of a lens determines what your camera can focus on, and how your images are going to turn out.
1. Field of view
How much is captured in an image.
Shorter focal length lenses are called wide-angle lenses because they allow you to get a wider field of view in one image.
Lenses with long focal lengths are called telephoto lenses and have a smaller field of view.
2. Depth of field.
Lenses with long focal lengths tend to have a shallow depth of field
they can focus in on small objects
lenses with short focal lengths have a larger depth of field
enables them to get a wider range of elements in focus.
3. Perspective.
Focal length can also change the perspective and scale of your images.
A lens with a shorter focal length “expands” perspective
giving the appearance of more space between the elements in your photo.
telephoto lenses tend to stack elements in the frame together to “compress” perspective.
4. Image shake.
Image shake is the blurriness and reduction in image quality that occurs from the vibration of pressing down the shutter release.
When using a lens with a long focal length and tight perspective
your lens and camera are more sensitive to the slightest motion
Image shake can be prevented by using a tripod.
Range and Uses
1. Short focal length
Short focal length lenses are used mostly in landscape photography
they have a wide angle of view.
wide-angle lenses make subjects appear smaller
which requires photographers to stand closer to fill the frame.
Short focal lengths are suitable for environmental portraiture
2.Standard focal length
50mm is the focal length that closest example of the human field of view.
Focal lengths closer to 50mm are flexible and used for every type of photography
3. Long focal lengths
Focal lengths from 70mm to 85mm and above are considered longer focal lengths
you can expect to see compression of distance and less distortion in longer focal lengths.
My Examples
All my images are of the same item taken with a Canon 2000d using a 18-300mm lens but taken at different settings. These images were taken in Manual, Raw, Adobe RBG and edited as required using Camera raw basic. My camera setting whereas shown below for each image You can clearly see the difference in the range of view in my images. The first appears closes as the last is further away.
1/60-f10-100
References
https://en.wikipedia.org/wiki/F-number control of Light
langfords basic Photography
https://www.masterclass.com/articles/basic-photography-101-guide-to-understanding-focal-length
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