Saturday, 9 May 2015

Understanding Apertures


What is Aperture?

Aperture is one of the three main functions in photography along with the shutter and the ISO.

The aperture is a ‘circular hole’ within the lens and is known as the ‘diaphragm’. To create an image, light passes through the ‘diaphragm’ and travels into the camera image sensor/film creating the image. The amount the ‘diaphragm’ is open to allow light through is measured in f-stops, i.e. f2.8, f4, f5.6, f11, f16, etc.

Beginners often get confused on what ‘f’ numbers mean and how they work. As a general rule: the smaller the ‘f’ number, the larger the opening of the aperture. The larger ‘f’ number, the smaller the opening of the aperture.

Therefore, f2.8 is considered as a large aperture. At f2.8 the diaphragm of the lens is larger and allows more light to come through and fall on the image sensor/film.

At f16, the aperture is small. The diaphragm of the lens is small limiting the amount of light passing through the lens and falling on the image sensor/film.

The below diagram shows the aperture in relation to its ‘f’ numbers: (not to scale)

                       



 How does the aperture work?

Just think about the human eye; the pupil controls the amount of light passing further into the eye by shrinking or expanding.

The aperture works exactly the same way. The amount of light is controlled by changing the f-stops on the camera. As you can see from the diagram, f2.8 allows much more light in than f32.

If the aperture is changed from one ‘f’ stop ‘either way’, it doubles or halves the size of aperture as well as the amount of light passing through.

Moving from f2.8 to f4 the amount of light is halved.


                            


Moving from f8 to f5.6the amount of light is doubled.

                         



When changing the aperture either way, it also affects the shutter speed (the amount of time the shutter is open) and the ‘Depth of Field’- (DOF is what controls the image sharpness).


Aperture and Focus

Choosing a large ‘f’ number such as f22 or f32 will bring all the foreground and background in focus. This aperture setting is always best to use when you want everything to be sharp and in focus.

This photograph has been taken using f22, as you can see everything is in focus from the foreground to the background.





On the other hand, a small ‘f’ numbers such as f2.8, f4 and f5.6 will blur the background, isolating the subject. This aperture setting is useful to use when you want to have parts of your photograph blurred to add impact as well as for photographing close-ups.

The 1st photograph has been taken using f2.8, as you can see the purple nail varnish bottle is in focus and the rest of the image is blurred. The 2nd photograph has been taken on f5.6.









For cameras that do not have aperture mode, use  ‘Landscape’ mode  for a large DOF.


And for a small DOF use the  ‘Close-up’ or the  ‘Portrait’ mode.






The aperture adds dimension to the photograph by either blurring the background or keeping everything in focus.

                  



Image Of The Day - 09.05.2015

Fitness Photo shoot

Model: Amy
Theme: Fitness
Location: Apollo Hotel, Basingstoke



Bhupinder Ghatahora
Ghatahora Photography
https://twitter.com/Ghatahora

Friday, 8 May 2015

Useful definitions


Useful definitions with examples of images (part 1)

Aperture: is the size of the hole in the lens which combined with the shutter speed, controls how much light gets into the camera.

Aperture mode / Aperture Priority: (AV) the mode that automatically calculates the shutter speed when you choose the aperture you want to use.

 Camera shake: is when the camera moves as you press the button, causing the image to be blurred.



Close-up / Macro: means close-up photography and is great to photographs of flowers, bugs, shells and other tiny objects.

Composition: arranging objects in the photographs that look pleasing. Also see Rule of Thirds.


  
Contrast: is the difference between the bright and the dark areas of the photo. High contrast image will show very dark and very light areas in the same photograph.

Normal Image (balanced contrast):


High Contrast Image:


  
Cropping: Cutting of the edges of your image, either by moving in closer to the subject or trimming the edges using photo editing software.

Uncropped Image:


Cropped Image:



Depth of field (DOF): shows the range of components in a scene, front to back that remain sharp. Shallow depth of field makes the objects sharp in the foreground only. Deep DOF makes everything in the image sharp from foreground to the background.

The image below is photographed using Shallow depth of field, using f5.6


The image below is photographed using Deep depth of field, using f16




Exposure: is the amount of light that is allowed to hit the camera sensor. Too much light results in Overexposed images, whereas too little light results in Underexposure of the image.

Correct Exposure:



Over Exposed Image:



Under Exposed Image:

Image of the Day - 08.05.2015

Image of the Day - 08.05.2015

Apollo Hotel, Basingstoke



Bhupinder Ghatahora
Ghatahora Photography
https://twitter.com/Ghatahora

Thursday, 7 May 2015

Morning & Night Photography


Photography during winter is fun, especially when the mornings are filled with mist and the light is golden. There are long shadows during sunset and frost throughout the day, beautifully formed on spider webs, plants and anything that touches the chill. Then there is snow, which creates its own unique atmosphere. But most importantly, the whole ambiance is a wonderland.

Even though it gets cold during these months, don’t let this put you off photography. Wear suitable clothing to keep warm and capture the beauty of nature in your photography.

In this article I will briefly explain how to take great photographs in different lighting conditions using the ISO, aperture, shutter, and manual mode of your camera.


Morning Photography

Before sunrise, the light reflected from the sky hitting the scene is very soft and diffused, which gives very weak shadows. The colour of the sky will be blue on a clear day and grey on a cloudy day, such lighting conditions can create very atmospheric photographs. This photograph was taken before the sunrise.



Use the Aperture Priority mode; set the aperture at f16 (the camera will automatically adjust the shutter speed).


For Manual mode, set the aperture at f16 and the shutter speed at 15 seconds. Use this shutter speed as a guide only, as your exposure time may vary depending on the available light. You may either have to increase or decrease the shutter speed depending on the image produced.

Cameras which do not have the Aperture Priority or Manual mode will often allow selecting different scene settings, such as ‘dusk/dawn’, ‘nightlight’ or ‘sunset’ modes. Please choose which suits you and your camera best.

Here is a photograph taken using Aperture Mode. The exposure will be long, so use a tripod as this will avoid camera shake. In this photograph the sun has just began to rise and you can see how the colours are different in both images.



If you don't have a SLR, it's still possile to get good photographs, just need to understand your camera and its modes. Read more on 'Understanding your Camera'. 

Example of photograph using ‘Dawn/dusk’ mode on a compact camera


During the morning also try to photograph the morning fog, water droplets on spiderwebs and frost. The photographs below are all taken with a compact camera. To get maximum depth of field, set your compact camera on 'Landascape Mode' (set f16 on SLR - using Aperture mode ) and for minimum depth of field set the camera on 'Close-up Mode' (set f2.8 of f5.6 on SLR - using Aperture mode). The result of using these settings will be similar.

Morning fog (camera set on 'Fog Mode')



Dew drops (camera set on 'Close-up Mode')



Night Photography

During total darkness, there is obviously no natural light available. These are perfect conditions to photograph trailing lights from cars, lit cityscapes, fireworks and light movement. 

If using Shutter mode, set your SLR on a slow shutter speeds such as 1/8th, 1/4th to capture movement. If using Manual mode, set the camera at f16 and use the camera’s exposure indicator to set the value on 0 as this will give you the correct exposure.


An exposure indicator is visible through the viewfinder which looks like:
2||||1||||0||||1||||2+.

On compact cameras choose 'Nightlight', and the camera will adjust the aperture and shutter accordingly.

Photograph of snow at night using Manual Mode:


It's great to experiment and be creative with photography. Try changing the ISO to 1600 or higher to minimise camera shake and to achieve moody, atmospheric photographs. I also convert my images to black/white to add more drama to it.


On compact cameras choose ‘Nightlight’ and the camera will adjust aperture and shutter speed accordingly.

Example of photograph using ‘Nightlight’ on a compact camera:


Bhupinder Ghatahora
Ghatahora Photography


Image of the Day - 07.05.2015

Image of the Day - 07.05.2015

Apollo Hotel, Basingstoke




Bhupinder Ghatahora
Ghatahora Photography
https://twitter.com/Ghatahora