Ansel Adams and his Zone System within Digital Photography
Background
Prior to DPP Assignment 2 I briefly touched upon Ansel Adams and his zone system.
In my research I find that though Ansel Adams is the man associated with the Zone system that he actually developed this with Fred Archer. With this system he gave black and white film photographers a tool to allow them to control their images.
The zone system was originally created to allow a controlled and standardized way of working to obtain and guarantee a correct exposure. Though created for black and white film photographers, and though created in 1940, it still has a place in the digital world and for images targeted as both black and white, and also colour.
The latest digital cameras have very good matrix metering that perhaps are able to correctly determine exposure in around 90-95% of cases. I mentioned and demonstrated in Assignment 2 how metering could be used creatively, particularly when using spot metering.
Its unusual and exceptional circumstances that can mislead the camera's metering system and incorrectly expose the image or expose the image differently from what the photographer intended.
The benefits of using the zone system are to enable correct exposures of scenes, enable an ability to determine a scene's tones and dynamic range, know how to determine how far apart to take bracketed shots for blending images into images of high dynamic range (HDR). HDR imaging is something I want to develop more skills and explore further. I have proposed some suggestions here to my tutor for Assignment 5 of DPP.
Camera metering will try to evaluate a scene and render it as an average reflectance, 18% grey. Its why we have grey cards, grey cleaning cloths and in the case of Michael freeman's books often an inside cover at 18% grey so that white balance setting can be obtained. However the correct way to set this using a grey card is for the this card to be placed near the subject of the intended image and spot metering for this to determine the WB setting (if not using Auto WB) and correct exposure. My knowledge of Infrared when attempting the same has determined that taking a reading of sunlit grass will achieve this.
So when the camera meters a scene of extreme brightness it will darken it and cause under exposure, and for a scene of too much darkness it will lighten it and cause over exposure
Zonal System
The zone system divides a scene into 10 zones with each zone of tones differing by 1 stop this each zone of tones across the scene differs by one stop.
Zone 5 (but not the middle of 10) is used to determine the middle tone, the tine with the average reflectance of 18%.
Now in relation to Ansel's use in black and white film, and meeting the challenge of my tutor in his feedback of DPP Assignment 2 for digital photography the darkest element of the scene recorded in this histogram is determined as Zone 3, point 0 on the histogram. For the brightest element its determined as Zone 7 and given point 255 on the histogram. This neatly puts Zone 5 in the middle between zones 3 and 7.
This is because in landscape images highlights and shadows are important. Light tones will lose detail after zone 7, and dark tones such shadows will lose detail before zone 3
How to measure using the Zonal system with a digital camera
Pointing my camera at an area of average reflectance should obtain an exposure reading of zero on the camera's meter.
Using the scale in one of my earlier posts I know that increasing the aperture by one stop or decreasing the shutter speed by one stop will over exposure the element I just metered by 1 stop making it lighter than it is. Doing the opposite with the aperture or shutter speed will allow me to darken this element by one stop making it appear in my image darker than it actually is.
Using the camera's spot meter in a scene and identifying the most important high light that should have maximum detail and vice-versa for the most important darks. So where elements fall out side the range of -2 stops and plus 2 stops form where you have decided to take an average meter reading to set to 18% then these areas outside will not be unlikely to have much detail captured. However detail can more easily be recovered from darks than it can whites so exposure should be judge so that the brightest pixels should be placed near to but not on the extreme right of the histogram.
When to use HDR and how to judge how far to over and under expose.
So using matrix metering your digital camera will expose based on what it determines the average reflectance of the scene to set at zone 5, or zero on the camera metering. By adjusting the exposure to over expose 1 stop at a time pressing the shutter at each and continue until the histogram shows a slight gap between the darks recorded and the left hand side of the histogram. Repeat this from the exposure settings identified originally and under expose until the histogram shows a slight gap between the lights and the right hand side of the histogram pressing the shutter each time. Combining this set of images will create a HDR image that has captured the complete dynamic range of the scene. Interestingly this is likely to create an image similar to what your eyes was able to determine.
I've exampled this below in a series of images using the troublesome kitchen and lighting conditions that caused me problems in Assignment 2
Your eyes moving around and across this scene, capable of much more dynamic range than the camera's sensor is in affect creating a rolling HDR film similar to what your eyes are creating for your brain.
Shooting this on film repeating say the camera panning and elapsed time and exposure increase and decrease as detailed above and combining these film images would then create a HDR fiilm / video.
The following linsk explains this in more detail with some good images to give greater understanding:
Understanding and Using Ansel Adams' Zone System
http://photography.tutsplus.com/tutorials/understanding-using-ansel-adams-zone-system--photo-5607
The Digital Zone System
An article from the Outdoor Photographer
http://www.outdoorphotographer.com/how-to/shooting/the-digital-zone-system.html#.U1gvAFVdU1I
Prior to DPP Assignment 2 I briefly touched upon Ansel Adams and his zone system.
In my research I find that though Ansel Adams is the man associated with the Zone system that he actually developed this with Fred Archer. With this system he gave black and white film photographers a tool to allow them to control their images.
The zone system was originally created to allow a controlled and standardized way of working to obtain and guarantee a correct exposure. Though created for black and white film photographers, and though created in 1940, it still has a place in the digital world and for images targeted as both black and white, and also colour.
The latest digital cameras have very good matrix metering that perhaps are able to correctly determine exposure in around 90-95% of cases. I mentioned and demonstrated in Assignment 2 how metering could be used creatively, particularly when using spot metering.
Its unusual and exceptional circumstances that can mislead the camera's metering system and incorrectly expose the image or expose the image differently from what the photographer intended.
The benefits of using the zone system are to enable correct exposures of scenes, enable an ability to determine a scene's tones and dynamic range, know how to determine how far apart to take bracketed shots for blending images into images of high dynamic range (HDR). HDR imaging is something I want to develop more skills and explore further. I have proposed some suggestions here to my tutor for Assignment 5 of DPP.
Camera metering will try to evaluate a scene and render it as an average reflectance, 18% grey. Its why we have grey cards, grey cleaning cloths and in the case of Michael freeman's books often an inside cover at 18% grey so that white balance setting can be obtained. However the correct way to set this using a grey card is for the this card to be placed near the subject of the intended image and spot metering for this to determine the WB setting (if not using Auto WB) and correct exposure. My knowledge of Infrared when attempting the same has determined that taking a reading of sunlit grass will achieve this.
So when the camera meters a scene of extreme brightness it will darken it and cause under exposure, and for a scene of too much darkness it will lighten it and cause over exposure
Zonal System
The zone system divides a scene into 10 zones with each zone of tones differing by 1 stop this each zone of tones across the scene differs by one stop.
Zone 5 (but not the middle of 10) is used to determine the middle tone, the tine with the average reflectance of 18%.
Now in relation to Ansel's use in black and white film, and meeting the challenge of my tutor in his feedback of DPP Assignment 2 for digital photography the darkest element of the scene recorded in this histogram is determined as Zone 3, point 0 on the histogram. For the brightest element its determined as Zone 7 and given point 255 on the histogram. This neatly puts Zone 5 in the middle between zones 3 and 7.
This is because in landscape images highlights and shadows are important. Light tones will lose detail after zone 7, and dark tones such shadows will lose detail before zone 3
How to measure using the Zonal system with a digital camera
Pointing my camera at an area of average reflectance should obtain an exposure reading of zero on the camera's meter.
Using the scale in one of my earlier posts I know that increasing the aperture by one stop or decreasing the shutter speed by one stop will over exposure the element I just metered by 1 stop making it lighter than it is. Doing the opposite with the aperture or shutter speed will allow me to darken this element by one stop making it appear in my image darker than it actually is.
Using the camera's spot meter in a scene and identifying the most important high light that should have maximum detail and vice-versa for the most important darks. So where elements fall out side the range of -2 stops and plus 2 stops form where you have decided to take an average meter reading to set to 18% then these areas outside will not be unlikely to have much detail captured. However detail can more easily be recovered from darks than it can whites so exposure should be judge so that the brightest pixels should be placed near to but not on the extreme right of the histogram.
When to use HDR and how to judge how far to over and under expose.
So using matrix metering your digital camera will expose based on what it determines the average reflectance of the scene to set at zone 5, or zero on the camera metering. By adjusting the exposure to over expose 1 stop at a time pressing the shutter at each and continue until the histogram shows a slight gap between the darks recorded and the left hand side of the histogram. Repeat this from the exposure settings identified originally and under expose until the histogram shows a slight gap between the lights and the right hand side of the histogram pressing the shutter each time. Combining this set of images will create a HDR image that has captured the complete dynamic range of the scene. Interestingly this is likely to create an image similar to what your eyes was able to determine.
I've exampled this below in a series of images using the troublesome kitchen and lighting conditions that caused me problems in Assignment 2
Your eyes moving around and across this scene, capable of much more dynamic range than the camera's sensor is in affect creating a rolling HDR film similar to what your eyes are creating for your brain.
Shooting this on film repeating say the camera panning and elapsed time and exposure increase and decrease as detailed above and combining these film images would then create a HDR fiilm / video.
The following linsk explains this in more detail with some good images to give greater understanding:
Understanding and Using Ansel Adams' Zone System
http://photography.tutsplus.com/tutorials/understanding-using-ansel-adams-zone-system--photo-5607
The Digital Zone System
An article from the Outdoor Photographer
http://www.outdoorphotographer.com/how-to/shooting/the-digital-zone-system.html#.U1gvAFVdU1I
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