To make optimal use
of your ammonet ImageServ, it will be helpful to understand the two aspects of "image size" applied to digital
images.
- "image dimensions" refers to the width and height of the image itself, quantified in pixels. The larger the number of pixels, the larger the image appears on the monitor. However, the monitor resolution also plays a role. At a monitor resolution
of 800 x 600 px, a common resolution for a 15 inch screen, an image 400 px wide will fill half the screen width. However, the same picture on a 17 inch monitor set to resolution 1024 x 768 px would cover less than 40% of the width. The image dimensions thus have three-fold consequences that need to be balanced against one another:
- too few pixels will result in a loss of detail
and general degradation of your image,
- pixel dimensions larger than your visitor's browser window will mean vertical and/or horizontal scrolling. This might be an unavoidable consequence of the need for detail, but in such a case you should ensure that scrolling is activated in your image display, otherwise parts of the image will be inaccessible to your visitor,
- too many pixels will contribute to a large file size and hence slow the download of your image.
The Edit option of ImageServ allows you to crop unwanted peripheral areas such as excess white border space from your image, and to
resize it to smaller dimensions that the original. The resize tool authentically recreates your image with smaller dimensions and a smaller file size.
- "image file size" refers to the KB weight of the file that contains your digitised image. The larger the image file size, the slower it will be to open in the browser window of your visitor. Image file size depends on the pixel dimensions of the image, as described above, and can be reduced by making the image smaller. However, image files can also contain a very great deal of redundant information. For example, .tif format image files contain data
defining all possible colours even when those colours are not present in the image. .tif files are so large and so varied in format that we do not allow them to be uploaded to
ImageServ via the uploader. Even .jpg files that have ostensibly had irrelevant information removed can be significantly compressed by the
ImageServ
optimise tool, reducing the image file size by 30 to 75% without affecting the quality of the visible image itself.
We therefore recommend that you use the ImageServ to upload and organise your files in a rational directory structure, and then
to resize them, when necessary, so that they are not wider than 750 px and not higher than 550 px. Providing the important details remain visible, your images can be much smaller. An image 350 px wide and 250 px high can provide considerable detail even of a panoramic view. Finally, use the
optimise tool to reduce file size to the minimum possible without compromising your image quality.
Once you are happy with the final product, we recommend that you delete any other versions of the image to avoid wasting your server disk space.