Digital Photography
Images For Internet Use
The important thing about images you
want to publish on the Internet is that their file size is small
without sacrificing quality.
As mentioned in File Types, you must use JPEG files (although other types such as PNG and GIFF are also used but we'll not go into that for now..).
As always, when working with your precious images, make sure you fiddle with a copy and leave the original in a safe and secure folder on your computer. A good idea is to create a folder called "Internet Pictures" and save a copy of the original file there to work with.
Open the copy of the image and do all the required Image Manipulation.
Next decide on the dimensions of your image. It is worth noting that most people browsing your images on the net will have their monitor set to a resolution of 800 x 600 pixels. So it is worth always keeping your images below these dimension - else they will fill the viewer's screen! You will find that most of your original digital images are much larger than required and must therefore be reduced in dimension.
For the sake of the SVSAC web site and uploading to the Pictures pages, we'll assume that you want to resize your image to 640 pixels (that's 640 pixels for the largest side - the other side will be smaller in proportion).
Most software will have a function to adjust the image size. When resizing your image it is important to constrain the proportions so that the image does not become distorted. Set the longest side to 640 pixels. This should automatically set the shortest side to around 420 pixels - but this obviously depends on the proportions of your image.
Now you are ready to save your image.
It is probably best to select 'Save As' to do this. Select as file type JPEG or JPG (it will probably default to this - but check to make sure). Then you should be given an option to set the compression of the file. The compression should be set at medium or more. The higher (or more) the compression setting, the lower the quality of the saved image (please read the File Types for more detail on this). Setting the compression to low will create a large file - so, to be save, stick to a medium setting.
Some software will have the options for saving JPEG files in numbers. The lower the number the less the compression and the higher the quality. Again, choose a middle number to prevent the file getting too big.
Once saved, the image is ready for uploading to the web.
Read
more about:
Pixel
Basics
Table
Of Resolutions
File
Types
Image
Manipulation
Images
For Internet
Use
Images
For Print