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The aim when I took these pictures was to learn about how to photograph interiors and get the maximum tonality out of the negatives. I am learning about the Zone System which is very useful to know if you want to achieve detail in highlights and shadows and also I am developing the film pushing the amount of time (or giving N+1 development) so that the upper zones or highlights have been pushed up a further zone but the shadows and lower zones stay where they are achieving this way a greater tonality.
I have a diagram that explains what happens to the tones with different developing times (the roman numerals refer to the different tonal zones):
To get an even better tonality I developed the film for 20 minutes and the developer was diluted in a 1-100 proportion. I used Rodinal which was patented by Dr. Momme Andresen in 1891. It is the oldest continuously-produced developer formula in the world. At high dilutions Rodinal works as a compensating developer, which means that as the chemicals get exhausted they stop working on the highlights but continue working on the mid tones, thus preventing blown highlights.
There is an useful website to get correct times for developing, it is www.digitalthruth.com
The film I used is Rollei Pan25 which, according to the ad, offers outstanding resolution, sharpness and edge contrast, coupled with extremely fine grain and a long tonal range. This film is ideal where maximum quality is required, and its clear base makes it perfect for scanning. The only fault is that the film is quite thin and it curls a lot making it difficult to scan the negatives an quite fiddly in general.
I took this pictures with a classic medium format camera ( Hasselblad Super Wide). This is the technical data for the following images:
Colour Darkroom:
Meter readings: the floor was on zone II and the sink on zone VI
Aperture: f11, 6 minutes
Sculpture workshop:
Meter readings: the girder was on zone II and the sink on zone VI
Aperture: f11, 150 seconds
Type room:
Meter readings: the back of the room was on zone II and the highlight under the fluorescent light on zone VII
Aperture: f11
When I tried to take some long exposure photographs with digital camera I found myself limited by the camera I was using. The noise in the digital camera is produced by different factors such us the ISO you choose and the thermal conditions. There are a lot of articles on the web talking about noise in digital cameras and how the fact that having more pixels doesn’t necessarily mean having a better image as they can produce more noise, so there are quite a few different factors to consider when using a digital camera such as lenses, pixel number and sensor size. Some articles talk about how digital noise could be solved by having a bigger sensor which only the most expensive cameras have. ( http://photo.net/equipment/digital/sensorsize/) . The problem I find with the information about digital cameras is that the technology is moving so fast that most information is obsolete in a year or two.
I found some basic notions about Noise in digital cameras on this website: www.cambridgeincolour.com
Random noise is characterized by intensity and color fluctuations above and below the actual image intensity. There will always be some random noise at any exposure length and it is most influenced by ISO speed. The pattern of random noise changes even if the exposure settings are identical
Fixed pattern noise includes what are called “hot pixels,” which are defined as such when a pixel’s intensity far surpasses that of the ambient random noise fluctuations. Fixed pattern noise generally appears in very long exposures and is exacerbated by higher temperatures. Fixed pattern noise is unique in that it will show almost the same distribution of hot pixels if taken under the same conditions (temperature, length of exposure, ISO speed).
A couple of examples of long exposures I took with digital cameras, the light source on the first image were 3 LED lights and on the second one it was natural evening light:
Canon G9, 400ISO, f8, 15”
Canon D400, 100ISO, f22, 15”
An “old” article (1991) examines the image resolution difference between film and digital: http://www.users.qwest.net/~rnclark/scandetail.htm#digicamres2
Although it is old information and much better photographic cameras are available in the market I believe it is still relevant when considering the use of a medium format film camera. In my case, I find that a medium format camera is more accesible to me than the high end digital cameras for purely financial reasons, and the image quality/resolution you can achieve with it, it’s said to be similar to the one you would achieve with a 30megapixel camera. This, of course, would be achieved by using a high end negative scanner (or a drum scanner). Still, if the final product is going to be a print it makes sense to me that I should start by taking my pictures with a medium format camera.
This may not be the clearest of examples but I thought it was worthy to observe the difference in tonality between my two pictures, No. 1 digital photograph and No.2 medium format photograph.
I discovered this photographer not long after I finished my earlier composition and in many ways his work relates to the technique I used on mine. I guess the idea is also related to HDR. He even has a name for the technique!! I haven’t been able to find out too much about him but I would like to as his methodology and subject matter are very inspirational and, I feel, close to my work.
Thomas Weinberger was born in Munich, Germany, in 1964. He studied architecture at the Technical University of Munich and at Università di Sapienza in Rome. In 2001 he started to dedicate himself to photography which is now his sole dedication. He photographs industrial architecture, roads and deserted streets and railways. His images have been called spectral arquitecture. The surreal lighting that envelops his work make this images feel like an alienated reality, empty spaces that in the absence of human and animated presence become the main protagonist.
The technique used in his photography has been described as Synthesis, he photographs his motif twice. He does this once at nighttime (using a large format and long exposure) and the other during daylight. He then digitally superimposes both images, creating an artificial fictional lighting that gives his images a fascinating atmosphere.
Marina Dubai, 2006
Below is the image I was talking about at the start of this blog:
Candida Höfer is a german photographer from Düsseldorf Art Academy (1976 until 1982). She studied with the renowned professors Bernd and Hilla Becher. She has a large collection of photographs of interiors in public spaces, cultural centers and historic palaces. Like the Bechers her photography follows a rythm of patterns. With her unique sense of aesthetics, she approaches her subject with a distance leaving us with an observer window to a space which has logic and order as well as showing us the human intention and certain melancholy derived from its absent inhabitants. A space that breathes with life. The expressive language of simplicity.
These two photographs are examples of her technique, her camera at the spectator’s eye level, using the available light and long exposures to create her unique view of her interior subjects.
Ballettzentrum Hamburg III,2000
Neue Nationalgalerie Berlin VIII, 2002
I have also observed a similar influences for my technique in my long exposure photography.
These pictures were taken by Michael Kenna, who was born in 1953 in Widnes, Lancashire, UK. He is well known for his night photography and his long exposures. He transmits a lot of emotion with his work, making haunting images out of the landscapes he photographs. One of his influences was photographer Bill Brandt with his high contrast atmospheric black & white prints. Michael Kenna was born in quite an industrial area and this had a definite influence on his photography and how he visually approaches structures. Most of his photography has an architectural content. In these pictures he presents a beauty from industrial structures captured by the ethereal light that only night photography and its subjective and unpredictable character can provide.
Golden Gate Bridge, Study #2, San Francisco, California, U.S.A. 1988
The Rouge, Study 5, Dearborn, Michigan, U.S.A. 1992
Ratcliffe Power Station, Study 44, Nottinghamshire, England. 2003
I was looking at websites where they spoke about long exposure photography and neutral density filters which stop the light that comes in through the lenses allowing a longer exposure photograph. I found this information from a photographer called Dan Heller. After reading his page I have made a decision that I will use a manual SLR medium format camera but only for B&W photography and I will use the digital camera for colour as digital capturing doesn’t suffer from Reciprocity Failure. At the same time I am aware that shooting a long exposure on digital may produce a lot of unwanted image noise. I’ll have to research what can be done about this.
RECIPROCITY LAW FAILURE is the loss in the exposure sensitivity of film. In ideal world, if the light intensity doubles, one can always halve the exposure time to obtain identical exposure on photographic materials. Or, when the light intensity halves, one can double the exposure time to compensate, but it doesn’t always apply. There are occasions when film cannot properly react to light following the reciprocity law.
Although the reciprocity law failure effect can take place with daylight photography, the long shutter exposures of night photography definitely suffer from this. This is caused by either a prolonged exposure period (more than 1/10 sec. shutter speed) or an extremely brief period of the shutter opening (shutter speeds faster than 1/2000 sec.).
To compensate for this failure on long exposures with black and white film the exposure time is extended. Different film manufactures recommend different guidelines in time adjustments.
This is the advice given by ILFORD on reciprocity law failure on film:
MAKING LONG EXPOSURES
For exposures between 1/2 and 1/10 000 second, no adjustments are needed for reciprocity law failure. When exposures longer than 1/2 second are given, HP5 Plus, along with other films, needs to be given more exposure than indicated by a meter. Use the graph to calculate the increased exposure time which should be given once the measured time is known
David Fokos
This is the technical information I found:
NEUTRAL DENSITY (ND) Filters come in many configurations, from one stop of light, up to thirteen stops, where each “stop” doubles the amount of time of your exposure because it blocks twice as much light as the previous stop. So, a picture that would normally taken at f16 @ 1/30 second can turn into a 30-second exposure with a 10-stop ND filter. People have been known to photograph the sun traveling across the sky all day using two 13-stop ND filters stacked on top of each other.
Reciprocity Failure simply refers to when the film fails to produce an image that represents the light that was projected onto it. Simply put, the longer the exposure, the more you have extend the time your camera meter says to get the correct image on the film. This is easiest to see in black and white film: if you meter a scene that shows a proper exposure of 1 second at f8, then doing the math, you should be able to double the time and the apertures to yield exactly the same picture: 2 seconds at f16, 4 second at f/32, and 8 seconds at f64. All of these should produce precisely the same image. However, for some films, “reciprocity failure” begins to emerge gradually as those exposure times increase, which may require (for example) extending the time exposure, even though the meter doesn’t say it should. For example, doubling of time to 16 seconds at f64 to get the same result you should have gotten using 8 seconds.
What’s going on is that the chemicals in film don’t react to light consistently across time. This doesn’t happen during short shutter speeds—those used during typical daytime photography, which explains why most people don’t see this. Even at longer shutter speeds, the degree of failure tends to be minimal and people overlook it. (It’s also easy to fix in the printing process, so it’s rarely a concern.) However, as the during of time expands to longer and longer exposures, the film begins to fail more dramatically, so you need to add more time than you think you should, just to get the picture you want.For black and white film, it’s simply a matter of extending the duration of time. However, color film is more complicated because it has more than just one chemical: it has at red, green and blue to deal with as well. (In fact, most films have more, but you get the idea.) Here, the reciprocity failure affects all of these chemicals, and, making things worse, they all react to light differently than one another. As it turns out, reds and blues failure much more quickly than green, causing long exposures tend to look very green. The longer the exposure, the more out of sync these colors appear to be.
Different films use different chemicals for colors, and some films add more “stabilizing” chemicals than others to reduce this effect somewhat. So, while every film “can” suffer from some degree of reciprocity failure, not all are equal, so there is no uniform way to solve the problem across the board. Those who shoot Fuji Velvia 50, for example, has a much more dramatic problem with “green shift” than Provia 100F does.Because film’s reciprocity to light fails gradually over time, and because different film types (and even similar films from different manufacturers) also vary, it’s impossible to predict the final result from any given picture. You can use coloured filters to “help” correct the problem, but the inconsistency of the films and the filters mean that you’re never going get precisely a color-balanced shot like the pictures you see here. Whenever you correct for one color, you throw off another. The goal, therefore, is to find the filter that approximates your picture as closely as possible—finding that middle ground—at which point, you have to correct images digitally, where you can individually manipulate each of the red, green and blue hues in the overall picture.
The FL-D filter is normally used to correct for the green hue from fluorescent lights. However, it could be used to correct for mild reciprocity failure in some moderately long exposures using slide film. For longer exposures, FL-Ds are often not enough to correct the green as necessary, so a 30cc Magenta filter could be used.
Choosing the best filter can be done, but it could be an effort of futility to get perfect. Each film type has its own table for reciprocity failure, which you can find this in the box that the film came in, or you can look up on the web. Ironically, print film (negative) tends to suffer less than slide film, and the blueness of Tungsten film also doesn’t have this problem that I’ve seen.
Information taken from: www.danheller.com/tech-longexp.html
