HDR and The Zone System
I set up a new gallery today just for monochrome photographs. Monochrome, otherwise known as ‘black and white’, is my favorite medium because it uses shape and texture to form an image rather than color. Monochrome conveys a feeling of nostalgia or timelessness and communicates mood with form and texture. It is also easier for the ‘analog’ photographer to control image contrast and tonal width using exposure, chemistry temperature, and development time.
While at the Silverdale Art Walk last Friday, a photographer who works with digital processes visited my venue. He explained high dynamic range (HDR) imaging to me. This process involves taking a series of digital photographs using successively low to high exposure values. I assume that those exposures are 1/3 to a full stop apart from each other. Using Adobe Photoshop, the RAW format images are blended together so that the lowest exposure values can be printed closer to the highest exposure values to minimize darkened shadows or blown-out highlights, thereby controlling contrast. This requires expensive high-end digital equipment, computers, and imaging software to create the final print.
The Zone System, developed by Ansel Adams, produces a similar effect. Density values on developed film range from Zone I, or pure black on the finished print, to Zone X which is pure white. Zone V is middle grey. Each zone is different from the next by one exposure value, or f-stop. By exposing the shadows at about Zone V and decreasing development time, a photographer can do essentially the same thing. The increased exposure brings out the details normally hidden in the shadows while the reduced development prevents details in the highlights from blowing out into Zone X, or pure white in the final print. Although this process was developed for sheet film, a photographer can make a series of exposures at various exposure values on roll film and choose the best image from the scan or contact sheet. Each film formulation is different so it takes a bit of experimentation to find the right exposure/development combination for a particular film. Modern film quality is consistent, so one roll of Plus-X film will behave like another roll of Plus-X film under the same exposure and development combination.
Although I have never used the HDR method, I can practice the Zone System with a film camera, a daylight processing tank, standard chemistry, a Nikon scanner, and my Macbook Pro. Best of all, I don’t have to worry about my hard earned money fading into obsolescence when the next digital innovation hits the market.
Not better, just different. I do wonder just how long a digital image will last over time, however.
While at the Silverdale Art Walk last Friday, a photographer who works with digital processes visited my venue. He explained high dynamic range (HDR) imaging to me. This process involves taking a series of digital photographs using successively low to high exposure values. I assume that those exposures are 1/3 to a full stop apart from each other. Using Adobe Photoshop, the RAW format images are blended together so that the lowest exposure values can be printed closer to the highest exposure values to minimize darkened shadows or blown-out highlights, thereby controlling contrast. This requires expensive high-end digital equipment, computers, and imaging software to create the final print.
The Zone System, developed by Ansel Adams, produces a similar effect. Density values on developed film range from Zone I, or pure black on the finished print, to Zone X which is pure white. Zone V is middle grey. Each zone is different from the next by one exposure value, or f-stop. By exposing the shadows at about Zone V and decreasing development time, a photographer can do essentially the same thing. The increased exposure brings out the details normally hidden in the shadows while the reduced development prevents details in the highlights from blowing out into Zone X, or pure white in the final print. Although this process was developed for sheet film, a photographer can make a series of exposures at various exposure values on roll film and choose the best image from the scan or contact sheet. Each film formulation is different so it takes a bit of experimentation to find the right exposure/development combination for a particular film. Modern film quality is consistent, so one roll of Plus-X film will behave like another roll of Plus-X film under the same exposure and development combination.
Although I have never used the HDR method, I can practice the Zone System with a film camera, a daylight processing tank, standard chemistry, a Nikon scanner, and my Macbook Pro. Best of all, I don’t have to worry about my hard earned money fading into obsolescence when the next digital innovation hits the market.
Not better, just different. I do wonder just how long a digital image will last over time, however.
