Manuals Frequently Asked Questions

The instruction manuals, literature, advertisements and brochures have been set up as web pages with re-scaled images or thumbnails of the pages. Clicking on the thumbnail opens up an image scanned at 300dpi. Most images are JPEG, which can be viewed and printed by a large range of graphical programs. 

The first manuals were provided in 1997 and there has been continual additions since October 2000.

Printing the pages back to back, cut to size and stapled creates a reproduction of the original.

The web page format is of thumbnails which form a menu and links to the full size image. Clicking on each thumbnail will display the image full size. To get to the next image you have return to the thumbnail page and select the next one from the menu. If the thumbnails appear in the side panel they form a menu for each page to appear in the main frame. This means that each page has to be called up singularly and at full size, but reduced memory problems and internet timeouts. If you get the menu options for the link (secondary button for PC users for the pop up menu) you can select the 'save link as' and view the image from the location saved to. This is more laborious, but with full 300dpi being used this allows full control on how much is downloaded at any time. The 300dpi scans are more than double the size of the 200dpi making many manuals 20Mb or more.

Feedback has been low, compared to the number viewing the index pages. Here are some guidelines to points raised.

What do the figures in Kb and Mb mean?

In the index and contents page for the manuals the handbook, brochure or advertisement are listed with the download size in Kilobytes or Megabytes. For pages with thumbnails this is an indication of the total download size for all the pages that can be called up. The thumbnail page itself will be up to 24 very small images (the pages) and load very quickly. Each page then selected by clicking on the thumbnail to open up the large scale image can be 300Kb-3Mb. 

Why not display them full size?

Showing the images as thumbnails enables the page required to be located easily and without a lot of scrolling.

The image can then be

Images selected by clicking on the thumbnails are shown full size, although your browser may choose to scale it to the size of your screen.

Why not use PDF format?

There is no saving in download time to include the pages of a handbook into an Abobe Acrobat PDF file. JPEG images are already compressed. Not all internet users have installed Acrobat reader and many are unable to download files much larger than 2Mb without problems. There is also no way to point someone to an article on two or three pages without them downloading everything.

Why not use ZIP to make a single download?

This was originally provided as an option. As with Abobe Acrobat PDF files there is no saving in download time and again there where problems with the large file and not all users having software that allows unzipping. A self extracting zip file would only work on some platforms. Also links to individual pages could not be provided. 

Why not give a choice?

It is not possible to store both original images and a secondary format. There are over 6600 pages online and over 4Gb of files. Including a secondary format would double the space required and take additional resources to create. Even with thumbnails the time to create the pages increases and each thumbnail is 4Kb requiring another 20Mb of storage.

Why not display the pages full screen one at a time?

Most pages are scanned at a resolution that makes viewing even a single page difficult on a small monitor. To view the pages the page has to be selected or forward and back buttons provided. Although a useful mechanism for a gallery of photographs it is not so useful for the user requiring a copy of the manual that will be printed with pages back to back to reproduce the original layout.

The thumbnail version of pages allows the 300dpi scans to be selected one at a time and this reduces the resources needed to that of a single page or double page spread at a time.

How to print as a book.

A web browser is not suitable for printing the pages. You can not control the scaling and page throws for all browsers and printers. This means that some images would be printed across two pages or outside the print area.

Save the web pages or individual images to a given location and use a graphics program to view the saved images.

For the images set the page format to be landscape (very few pages print portrait) and centre the image on the page. When turning the page over the next page (odd and even) can be printed and then should line up. If you can centre the page at the top and at the bottom (a 10mm top margin is usually ample) then 8 pages can be printed on one sheet, two images per side (normally with two pages each) and both sides of the paper. Cut to size and fold.

Some experimentation may be necessary to work out how to print on the back of first print, unless you are lucky enough to have a full duplex printer that prints double sided.

Scanned Images are Crosshatched, Show a Herringbone or Checkerboard Pattern

Scanned pictures, photos, and images that are checked, blotchy, crosshatched, show a herringbone or checkerboard pattern, or have diagonal or horizontal stripes are displaying a type of interference known as moiré.

This is a limitation of the original scanner. Scans are taken at the optical resolution of 200 dpi or 300dpi. Increasing the scaling makes for larger images, but the problem persists.

Pictures from magazines, newspapers or any other printed material are halftone images (images that have been printed using a layering of black and coloured dots to reproduce an image). Scanning a halftone image repeats this layering process and, due to different sampling rates and dots-per-inch, the moiré effect is sometimes seen. Good quality scans are still possible by using the HP Precisionscan Pro Descreening Tool to correct the effects of moiré interference. These images scale better on screen but are still not as good as the 600dpi images that are very close to the original under a magnifying glass but show the moiré effect when scaled. Unfortunately these 600dpi images are 9 times the size and so the 2Gb of manuals (January 2004) becomes at least 18Gb. As a compromise all future scans are done at 300dpi.

Marks on the page 

After the pages have been scanned they are rotated for viewing and the white area around the text cleaned up to remove stains, aging and pencil or ball point marks on the original.

This results in text that is easier to read with a higher contrast and may reduce the size of the image to download. Some page discolouration may still be visible but may take pixel editing to clean up further.

Large (A3) scans

Occasionally folded brochures are larger than A4 (210x290mm) and larger than the scanner's viewing area. The multiple scans have been combined into a single image. Although you can scale these images to print on standard A4 pages the preferred choice would be to use an A3 or larger printer. For jacket covers one approach is to use a graphics program to select the front and back separately and to print on two or four (inside flaps) parts, cut to size and tape together. The transparent plastic sheet for covering books and posters is ideal for fixing the parts seamlessly together.

Original or re-created?

A few manuals have pages missing. The inside flap on some has been lost. Sometimes it has been possible to re-create the appearance of the original by including an almost identical page from an earlier or later manual in the series.

Some manuals have been available only in one language, or an original in one language with good photo images but a second one in English or German is only a photocopy.  In this case the photocopied text has been pasted over the scan of an original manual. If this has been done then it usually obvious, but a note to that affect will be included on the page.

Why not create Web documents of the manuals?

The original idea was to read the text using optical character recognition software and linking in images as they appeared in the original. Some text appears over images and often the text refers to images by location on a page. The result of doing this was less than satisfactory and was resource intensive. OCR may be used if pages are included in an Acrobat PFD file to provide search and indexing of the content.


Go to the main index Last Updated on 22nd February 2008