Offset Printing (The Prepress)

Printing is still a very important industry, even though electronic media has taken some of it’s role in spreading knowledge through Internet and e-documents in today modern world. Printing items such as books, brochures, fliers, calendars and much more, however are still needed in their old fashion way.When we talk about off-set printing most people will think that it only involves the process of transferring images from printing plates to paper (press) using the printing machine, however, the actual printing processes that we have to consider start from receiving manuscript or draft making until the final finish products. It can be divided into three parts, that are, prepress, press and post press. In this article as an introduction, I will try to elaborate the first part of the printing processes.

The Prepress

Prepress processes include the work of draft layout, typesetting, graphic designing, proofreading, copy editing, page assembly, color separating, film producing and plate making. In modern printing technology this process is also known as Desktop Publishing (DTP). Typesetter or graphic designers who are responsible in carrying out this job usually have good skills, knowledge and talent in manipulating some of the commercial graphic or image editing software for instance Illustrator, Photoshop and InDesign (of the Adobe Creative Suite), Adobe Pagemaker, QuarkXPress, CorelDraw, Microsoft Publisher or the free open source software such as Inkscape, (with capabilities similar to Illustrator, Freehand and CorelDraw) and Scribus, program that brings professional page layout to Linux/Unix, MacOS X, and Windows desktops with a combination of press-ready output and new approaches to page layout and also supports professional publishing features, such as CMYK color, separations, ICC color management and versatile PDF creation.

Nowadays, the images created in the Desktop Publishing (DTP) application can be output directly to printing plates and are called Computer To Plate (CTP) output - such as Suprasetter thermal CTP system from Heidelberg, Elantrix H CTP system from Agfa etc. Whereas in older technology, images are firstly produced to films - Computer To Film (CTF) using the imagesetter, and then it will be contacted and exposed to plates in an exposing machine. The resolution on a typical image setter is 1270 or 2540 dpi with a maximum dpi of 4000.

In a single color printing items such as a text book content, only one plate will be produced using one of the above plate making process, where as in full color items such as colorful brochures, color images will be separated into 4 colors that are Cyan, Magenta, Yellow and Black and abbreviated as CMYK to produce 4 printing plates. Even in some printing items, additional plates (for spot colors – such as gold, silver or customized colors) are needed.

Plate making processes have a very important role in determining the quality of the item to be produced. The machine has to be professionally calibrated, because a slightest different in images screen or density of one of the plates, may result in bad printing outputs.

The good produced plates will be used in the second part of the printing processes, that is the Press.

Global Warming, Desalination and Marine Life

"A world without fresh water would be a world bereft of humans, and yet one in five people lacks regular access to this most basic of life-sustaining substances. By 2025, fully a third of the planet's growing population could find itself scavenging for safe drinking water".


"One third of the planet will be desert by the year 2100" say climate experts in the most direct warning yet of the effects of global warming".


"More and more countries facing extreme drought conditions are looking towards desalination as a last hope for a source of freshwater".


"Untreated sewage is a big problem that leads to the loss of coral reefs but global warming has created difficult conditions for marine fauna and flora, the rising sea levels and the effects of seaward development" say conservationist.






From these statements from four different experts we some how have to admit that they are referring to the problems that the world are facing now.


Two things are clear about fresh water in the future: There will be less of it and we will pay more for what much of the world now takes for granted. The Global Environment Facility, an environmental fund, has said that water crisis is now a global concern with water scarcity the dominating issue of discussion amongst relevant institutions throughout the world.


Is the Sea Water Reverse Osmosis (SWRO) desalination contribute to global warming?


A major advantage of desalination of sea water is that water is always available even in the most severe droughts. Extracting salt from seawater to make it drinkable is the wrong way to handle water shortages around the world and could exacerbate climate change, a leading conservation group said however independent scientists disputed the findings and said desalination plays a minor role in global warming.


Some country like North Africa and the Middle East which is the world's most water-scarce region, has to turn to seawater as the source of fresh water through desalination process. Desalination has become a growing trend particularly in Australia, the Middle East, Spain, the United Kingdom, the United States, India and China.


Saudi Arabia, the world's largest producer of desalinated water with 27 desalination plants provide drinking water to major urban and industrial centers through a network of water pipes running for more than 2,300 miles. Desalination meets 70% of the Kingdom's drinking water requirement and several new desalination plants are under construction by the French utility services group Veolia, worth 702 million Euros and expected to be completed by 2010. Once completed, the Kingdom's network of desalination plants will have a capacity of 800 million gallons a day however there are power plants which produce energy and do desalination at the same time.


China, which is severely hit by water shortages, will turn to the ocean as it has announced recently it would utilize directly around 50 billion cubic meters of sea water each year by 2010 and plans to use desalination to produce 800 million to one billion liters of fresh water per day to cover about 20 percent of the demand gap in coastal areas.


The Ashkelon seawater reverse osmosis (SWRO) plant in Israel– the largest in the world – with a capacity of 320,000 cubic meters per day, produces around 13% of the country's domestic consumer demand – equivalent to 5–6% of Israel's total water needs.


South East Asia country like Singapore which already have a long term raw water agreement with their neighbor country Malaysia, also have a SWRO desalination plant in Tuas – one of the world's largest desalination plants and is paying Dutch experts tens of millions to devise ways to protect their island – ranks among the most energy efficient ever constructed, enabling it to achieve the lowest desalinated seawater price in the world.




Global warming and desalination pose a threat to marine fauna and flora?

The rising of marine temperatures (which most scientists blamed on the emission of greenhouse gases), influence all kinds of ocean conditions, including sea levels, marine ecosystems and the circulation of the deep ocean between the poles and the tropics.

The species affected range from plankton, which forms the basis of marine food chains, through to polar bears, walruses, seals, sea lions, penguins, various seabird species and coral reefs. Global warming could be the knock-out punch for many species which are already under stress from over-fishing and habitat loss. Even the coldest, darkest depths of the world's oceans can't escape the harmful effects of global warming - and that includes deep-sea corals and 'living fossil' fish. They've outlived the dinosaurs and a whole lot more, but global warming may yet kill off the coelacanth. Scientists fear the coelacanth - a "living fossil" fish that has been swimming the seas for an astonishing 400 million years - will be threatened if changes in ocean temperatures leading to the destruction of life - nurturing coral reef systems.


Coral reefs are delicate, yet they are one of the most important ecosystems in the marine world. They are home to thousands of marine species including clams, lobsters and other marine life and are a biological source for drugs. They have the highest primary productivity of any coastal ecosystems and are the breeding ground for over 3,000 species of marine life.



How desalination effected marine life?


1-As the seawater is taken in during SWRO desalination process, small life forms such as plankton, eggs and fish larvae are also removed.


2-The brine — the highly concentrated saline water — discharged from the plants is mostly sent back into the sea where it increases the salinity of the water, posing a threat to sea life and disrupting the ecosystem.


How to minimize the environmental impact?


Discharge the brine far enough from the coast so that it can dilute or finding alternative uses for the saline discharge in other industrial processes might minimize the environmental impact especially to marine life.

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