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From the beginning of my project my aim has been to capture some of what remains of the architecture of the industrial era in an attempt to represent this period of time through modern digital technology and in this way make a connection between our current digital revolution and the industrial revolution of the 19th & 20th century.
This essay is a reflection on my two year journey into the project, on my learning, development and contextualization of ‘Industrialism brought forward’.
This is the link to the PDF file of my essay
The digital photographic files of the valves have been worked in post production. I have worked methodically on them and I have now finalised them. Just to recap, the process followed was:
1. I got a bracketed exposure of my referent, minimum of 3 different ev
2. I imported them into Photomatix and created an HDR tonnedmapped image
3. I opened the image in Photoshop and made it Black and White. These changed the tonal values quite a bit, to compensate for this I had to make adjustments that vary slightly on each valve picture. For this particular valve, I choose a blue photo filter (making reds and oranges become a touch darker and blues and greens slightly lighter) and a touch more red with colour balance to enhance the texture on the dark areas. I also corrected the levels of the center bolt as the HDR process had made the white tones on this particular area expand and loose detail. Then to finish the overall correction of tonality I made an adjustment with the Curves, this varies greatly from valve to valve, it just has to be adjusted till you feel happy with the result. Keeping in mind that my monitor is from an Imac and although I use RGB (1998) as a standard profile, my monitor is not properly calibrated, so, what you see on the screen may not look precisely like what comes out of a printer.
After all the adjustments have been made then I create a mask that isolates the valve and allows the different exposure background to be seen. This is a lengthy process but well worthy. Creating this result:
To prepare this images to be printed onto a positive transparency I need to make sure that the resolution is at 360 ppi which provides optimum sharpness, based on the fact that it can be divided evenly into 1440 or 2880 printer driver resolutions. The size of the transparency should be smaller than the size of the plate. If the transparency is larger than the plate, the transparency gets bent over the lip of the plate, causing a dark shadow along the perimeter in some cases.
In order to get a broader range of shadow detail, I compensated with a tonal curve, which is, in fact, required to get the broadest range of shadow detail from the print. Most of the image detail is natively retained using the approach contained herein, however shadow detail will get buried in most images without an adjustment to the curve. A good process compensation curve basically lowers the contrast of the image, adjusting the entry levels for the black of the compensation curve to 94%. Contrast is then naturally reintroduced when it gets transferred to polymer plate. Without it, the image will appear too contrasty – especially in the blacks.
As a final check on the flattened image, I made sure that the histogram represented covered the entire length of the graph, checking with the Threshold tool and finally converted the image to 8 bit.
Low Hall Pump House is a Grade II listed building constructed in 1885 it houses Marshall C Class engines from 1896.
Information from www.leavalleyexperience.co.uk
The building was constructed of London stock brick with blue engineering bricks around the doors and windows.
The two Hayward Tyler steam pumps that moved the effluent were situated in a pit at the front end of the building. The steam power was generated by two boilers situated in the left bay.
It is also recorded in the Councils minutes of 1885 that Tangyes of Birmingham also installed a single horizontal engine for the cost of £420 which was situated next to the pit, however, what this engine was installed for still remains a mystery today despite research.
Accommodation for the chief engine room attendant was provided in No. 1 Farm Cottages in Acacia Road at a rent of 10/- per week.
The pump pit was filled in during the 1970s and is currently being excavated
The Pump House 1896
In 1896 the two 1885 bays were enlarged and a third bay was added to the left of the building. The Marshall C class steam engines, boilers, and plant equipment were also added at this time; however no plans of the 1896 extension have been found to-date.
Tenders were invited by the Council in early 1896 for designs on a way to connect the new Marshalls engines with the original 1885 Hayward Tyler steam pumps.
We have presumed that this must have been successful and the engines did in fact power the pumps via overhead line shafting, of which can still be seen today.
In addition to this various pieces of workshop equipment were placed in the pump house. The engines also provided the power to drive these machines. Originally fuelled by coal, the steam plant was converted in the early 1900s to work from domestic refuse which was burnt elsewhere on the site.
However, by the early 1970s the general state of the boiler made the raising of steam then a rather haphazard affair. The installation of electrically powered pumps then sealed the engines’ fate, and a large part of the 1885 buildings was demolished The Great Eastern Railway also provided a connection to the site from Lea Bridge Road. The site also had a small locomotive shed and locomotive at one. From 1928 the pumps moved sewerage directly into the LCC sewerage system. time.
The Pump House Today
The pump house today contains what are believed to be the only surviving pair of “C” class horizontal steam engines built by the Lincolnshire firm of William Marshall Sons & Co.
• The engines are also Grade II listed along with the steel beams within the building.
• The installation of these engines and a boiler cost £220.
Today, Marshall’s are best remembered as builders of traction engines, but in their nineteenth century heyday the firm produced an extraordinarily diverse range of products, from threshing machines to tea plantation equipment.
The two engines bear the makers’ numbers 27834 and 27835 and were installed in the pump house during the spring of 1897, being steamed for the first time in May of that year.
The engines were not designed to (and cannot be) run together – rather, one engine would have worked for two weeks running continuously whilst the other received maintenance.
It would have taken about forty minutes to disconnect one engine from the flywheel and to connect the other. This process was generally carried out in the early hours of the morning when the sewerage flow was at its slackest.
The Low Hall Manor and the Farm
The area now occupied by the Museum was purchased from the Bosanquet family in 1877 by Walthamstow Urban District Council.
Prior to this, the 200 acre site had been farmed from at least the early mediaeval period (traces of a moat which surrounded the mediaeval manor house and farm survived until comparatively recently).
Although the site is therefore of considerable antiquity, today nothing remains above ground of the original seventeenth century manor house and farm as they were both completely destroyed by a flying bomb in 1944.
In 1997 the site was excavated by MOLAS (Museum of London Archaeology Service), and a number of interesting artefacts were found. It is proposed to display some of these at the museum in the future.
My practice
This is a close up of a valve from William Marshall Sons & Co. “C” class horizontal steam engine. I took three different exposures and using Photomatix – for info on this technique see my high dynamic range post – I created a tone mapped image, which I then converted into black&white.
Looking at this picture and thinking about the New Objectivity movement, I should mention in this post Wolfgang Sievers (1913 -2007), a german industrial photographer which work followed these set of aesthetics. At the start of his career, his photography was imbued with the Bauhaus ethos and philosophy of the New Objectivity he had learned in Berlin, combined with a socialist belief in the inherent dignity of labour. His photographs were often quite theatrical, as he commonly photographed industrial machinery at night, isolating details with artificial light and posing workers for heightened effect. This can be seen in ‘Gears for Mining Industry’ (1967), perhaps his most well known single image. This approach was extraordinarily influential in Australian post-war commercial photography.
Gears for mining industry. 1967
Aluminium ingots, Alcoa of Australia at Point Henry near Geelong, Victoria, 1970
Associated Pulp and Paper Mills, Burnie, Tasmania, 1956
Largely self-taught as a photographer, Wolfgang Sievers lived in Portugal from 1934 to 1935 and his early work was commemorated by a retrospective exhibition in Lisbon in 1999. He returned to Germany in 1936, and studied at the Contempora School for Modern Applied Arts (a successor to the Bauhaus), and also taught there briefly. He left Germany in June 1938 and by October had set up as a photographer in Melbourne, attracting influential patrons such as Maie Casey. Talking about photographing architecture he said: “The task of a responsible photographer is not to discover some bits and pieces or some interesting perspectives but to interpret a great work of art in his own way”.
The Zone System long associated with Ansel Adams and Fred Archer is a technique used to learn how to pre-visualize. Pre-visualization stands for the act of looking at a scene with the physical eye and seeing in the mind’s eye how a medium such as traditional black and white photography can render the subject.
The Zone System is a good methodology as it demystifies technique. Understanding it allows a simplification of the traditional photographic process (exposure, developing and printing). By getting perfect negatives with a precise exposure you reduce the time of post-production to get the results you desire.
TECHNIQUE
The Zone System splits any given scene into tonal zones, 11 steps of tonal values which the human eye can recognise. Adams and Archer took the spectrum of print values, from black to white, and, using f-stops as the standard of measurement, simply assigned a Zone to each value that each f-stop of exposure produced. This results in a Zone Scale, which is a visual representation of PRINT values from black to white. This technique can also be applied to colour negatives.
Zones are always represented in Roman Numerals. Zone 0 represents the maximum black that the print can produce. Zone X represents pure paper-base white – no image. The mid-grey is in Zone V, the middle of the scale.
The light meter provides exposure settings for Zone V, giving a correct exposure for a known Zone. That’s the starting point. By adjusting exposure the subject can be placed in any Zone, up or down the scale, from the starting point. The subject will assume the tonal value of the Zone in which it is placed.
“Expose for the shadows; develop for the highlights.”
Zone placement can be also controlled by the development of the B&W negative.
Shadow density is controlled predominately by exposure. Highlight density is controlled predominately by developing time. A little additional development will not significantly affect shadows, but will push highlights up the scale. As developing time is increased, negative densities increase, but highlight densities will increase the fastest. Therefore, contrast also increases with increased developing time. This is referred to as N+1, “normal development plus additional development to achieve one additional Zone.” N+2 implies two additional Zones.
Zone description
| 0 | Pure black |
| I | Near black, with slight tonality but no texture |
| II | Textured black; the darkest part of the image in which slight detail recorded |
| III | Average dark materials and low values showing adequate texture |
| IV | Average dark foliage, dark stone, or landscape shadows |
| V | Middle grey: clear north sky; dark skin, average weathered wood |
| VI | Average light skin;light stone; shadows on snow in sunlit landscapes |
| VII | Very light skin; shadows in snow with acute side lighting |
| VIII | Lightest tone with texture: textured snow |
| IX | Slight tone without texture; glaring snow |
| X | Pure white: light sources and specula reflections |
Digital photography
The Zone System can be used in digital photography just as in film photography; Adams (1981, xiii) himself anticipated the digital image. As with colour reversal film, normal procedure is to expose for the highlights and process for the shadows.
One way to expose a photograph correctly with a digital camera using the camera’s little LCD window, would be to take a quick reference meter reading of your subject and note where the histogram falls on the scale from right to left.
A histogram shows the concentration of tones, running from dark on the left to light on the right, it can be used to judge whether a full tonal range has been captured, or whether the exposure should be adjusted. Varying the exposure one or two stops would correct the image if it is too dark, the histogram should be as far right as it needs to be to avoid the problems caused by expanding the contrast.
Digital camera previews are generated based upon different assumptions, one of those assumptions being that the image is being taken as a JPEG. This means that when shooting RAW files the histogram that the camera creates won’t precisely match the one that will eventually be worked on. Raw files can recover highlights that may seem to be “blown out” on the histogram.
Applying the Zone System maybe a better way to take a correct exposure. The subject highlight values can be placed accurately on the Zone Scale. It is a similar system to that used with colour reversal film. In this case the subject needs to be exposed for the highlights.
If your in-camera light meter has a spot metering function, or if you have a hand held spot meter:
- Carefully meter the Zone VII important highlights of your subject
- Make note of the meter’s recommended exposure
- Since Zone V is two stops darker than Zone VII, opening up two stops from the meter’s recommended exposure for the textures highlight will accurately place them on Zone VII. This will be the perfect exposure for digital cameras. EG: 1/125 @f/22 becomes 1/30 @ f/22
HDR
Another method of getting great scene contrast can be accommodated by making one or more exposures of the same scene using different exposure settings and then combining those images.
Automatic layer alignment in the image editing software makes this combining easier. The image then can be combined in HDR software that assists precise registration of multiple images.
Similarly to traditional photography we need to take into account the postproduction on a digital image, every step is important. The tonal range of the final image depends on the characteristics of the display medium. Monitor contrast can vary significantly, depending on the type (CRT, LCD, etc.), model, and calibration. A computer printer’s tonal output depends on the number of inks used and the paper on which it is printed.
Digital exposing for the highlights
It should now be clear that there are important technical advantages to properly exposing digital image files, but using the Zone system with 35mm cameras always requires some extra efforts.
With roll film cameras the problem always is: how to apply individual contrast control to frames that must be developed together. That isn’t a problem with digital 35mm frames, but there is still the issue of metering selected areas with built-in light meters.
Since it’s so easy to preview digital photographs using the camera’s little LCD window, one practical solution would be to take a quick reference meter reading of your subject and note where the histogram falls on the scale from right to left.
If the image is too dark, you could simply open one or two stops using either apertures of shutter speeds until the histogram is as far right as it needs to be to avoid the problems caused by expanding the contrast.
Moving the histogram too far to the right would be overexposure and cause the subject’s highlight values to fall off the edge of the histogram where they would be lost.
This is a very quick and very simple exposure method (and this is what many digital photographers actually do), but there is one issue that, shooting raw image files makes this approach less precise that it appears to be.
As mentioned above, digital camera previews are generated based upon assumptions about how you will eventually want to use the image. One of those assumptions is that you’re shooting for jpeg images that are compressed. When shooting in raw format, this means that the histogram the camera creates won’t precisely match the one you will eventually be working with. This issue also applies to the flashing ‘out of gamma’ highlight warnings that are a function of many digital slr cameras. When the preview is set to this function it can give the alarming impression that the highlights are blown out when, if shooting in raw format, they may be recoverable.
HDR images are the combination of a series of bracketed exposures into a single image which encompasses the tonal detail of the entire series. HDR enable a greater range of tonal detail.
image by Bettina & Uwe Steinmueller
Capturing identically positioned images and bracketing your exposure by varying the shutter speed (this way the camera can dramaticaly change the amount of light that lets in) will provide you with different tone images which you can use to merge to HDR. At least three different exposures are recommended for optimum accuracy in an even tonal distribution.
Some cameras have a setting called Auto Exposure Bracketing (AEB) it allows you to take 3 or more images with a chosen change of exposure. In order to uses this setting for HDR you need a camera that allows your shoots to be spaced by more than one EV step. Another important factor is the number of frames per second (burst rate) as a slow bus rate will have the disadvantage of anything moving on the image will become blurred and it will produce ghosting as it moves across the 3 images.
Adobe Photoshop will combine all exposures into a single 32-bit HDR file. As it stands, very few image processing functions can be applied to a 32-bit HDR file, so it is of little use other than for archival purposes. The image may still appear quite dark; only once it has been converted into a 16 or 8-bit image (using tonal mapping) will it begin to look more like the desired result.
Using tonal mapping you convert the HDR image into a 16-bit image. There are several tonal mapping methods. When you convert your HDR image to 8bits/channel you will get the options of different methods including Local Adaptation, which is the most flexible method and probably the one which is of most use to photographers. Unlike the other methods, this one changes how much it brightens or darkens regions on a per-pixel basis. This has the effect of tricking the eye into thinking that the image has more contrast, which is often critical in contrast-deprived HDR images. This method also allows changing the tonal curve to better suit the image.
HDR images which have been converted into 8 or 16-bit often require touching up in order to improve their color accuracy. Subtle use of levels and saturation can drastically improve problem areas in the image.
** information via www.cambridgeincolour.com**
Another program that has been recommended to use for creating HDR files is Photomatix Pro is a standalone application offering two methods of tone mapping, six methods of exposure blending, an alignment tool for out-of-register images, 16-bit support, and batch processing. The latest version of Photomatix will detect if your TIFF’s have the same EXIF (Exchangeable Image File Format) info and it will ask you to confirm which images have which exposure settings. This means you don’t have to remove the EXIF from them anymore.
