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Past Pages
Antique Maps, Prints and Ephemera



Print  Details

This page is intended to give a feel for the level of detail in illustrations of prints.
The main web site illustrations do not do justice to the detail or print quality of many prints.
The 3 examples here show the typical thumbnail image and the web page displayed image.
The third illustration shows the level of detail not shown in the main illustrations.

General photography loses a lot of detail in the way it captures and saves data.
If the screen image is sized the same as the physical print there is no comparison of quality.
The pixels per inch, or centimetre, are far less on the screen than from the original photo.
Even the enlarged detail photo does not contain detail information shown on the physical print.
The characteristics of a JPG image are to compact the file size by reducing the image quality.
The first things to suffer are fine lines and sharp edges.
BMP and PNG file formats retain full detail but are much larger in size.
JPG format balances file size and quality - it is the default for general photography.

Example 3 shows file sizes for each image and the file format of the image.
Notice the quality difference between digital camera and scanner, and the file formats.
Web pages are always fighting a battle between file quality and size.
With download speeds so variable around the world there is still a requirement to keep file sizes under control.

In all cases your print's quality will far surpass that of the displayed image.


Example 1








Example 2









Example 3


Thumbnail image  (3K JPG)



Typical web page display image from digital camera  (78K  JPG)



Detail from digital camera  (141K  JPG)



Greater detail from digital camera  (94K  JPG)





Detail from digital scanner  ( 970K  BMP)
Note the colour anomaly in the shadow above the horse's head and between the railings.
This is a side effect of the scanner processing very fine detail.
On the original print these are just fine black lines.
The digital camera would not resolve this level of detail and would produce a uniform grey shadow.



Detail from digital scanner  (875K  PNG)




Detail from digital scanner  ( 277K  JPG)




This is a reduction of the full size image from the digital scanner.  ( 843K PNG )
The file size for the hi-res version of this scanned image is 9.44MB
The wavy lines in the clouds are a feature of the scanner reacting to the engraved lines.
This visual anomaly is removed when using the digital camera.



Full size detail of Hi-Res scanning anomaly.     (This portion:  525KB)
The scanner is incorrectly resolving red, green and blue from plain black lines.






A Past Pages Information page      www.pastpages.co.uk              Tony Nicholls  2012