|Back to Text-only Web Page|
This is a guide for people submitting photos to our Project Gallery. It gives a basic overview of how image files work on the Internet, and some specific guidelines about posting your images here. Even if you have experience with Internet graphic images, please check the specific guidelines below.
Photographs can be scanned into a digital image file, or you can take digital photographs directly using a digital camera.
The format of the digital image file is important. There are many digital file format, but we (and the Internet in general) uses two main format: GIF and JPG (or JPEG). If your digital image file is in another format, you will need to convert it into either GIF or JPG format.
JPG: Best for photographs because they can contain over 16 million colors and can be compressed into a small size. When you save a JPG image, you can typically control the amount of compression. This is described below.
GIF: Used for web animation and can contain up to 256 colors. Generally, you should not choose this image format for photographis - it is much better suited to images with section of solid colors, such as line art, cartoons, or drawings.
Compressing JPG Images
It is important to get the smallest possible image file, because every person who wants to view your image will have to download it.
The more you compress a JPG image, the smaller the file is. However, you lose image quality rather drastically beyond a certain amount of compression.
The key to good compression is to set the compression factor just below where the image starts to degrade noticably. You may need to experiment to get the right setting.
When you save a JPG image, you are usually get to choose the compression factor. The actual factor can be 1 to 10, 1 to 100, or any other range. Also, depending on the software, the low end or the high end can mean “no compression”. For example, Corel Draw typically uses a 1 to 100 range, with 100 being maximum compression (and horribly blurred image quality).
The best software package lets you preview the image instantly as you change the compression factor. You can just adjust the factor to maximize the compression without noticably affecting image quality. If your software does not have a preview feature, you may need to save the file with several compression factors, and view the images side-by-side.
There is no standard amount of compression that is good for all images, but it is typically between 3 and 7 on a 1-to-10 scale.
The other key issue is the size of your image. A very large image requires the user to scroll (annoying) and causes a very long download time (very annoying).
Most monitors show about 80 pixels per inch. So, to show a photo the same size as standard 4" by 6" snapshots, and image which is about 320 pixels by 480 pixels is good. Please limit photos to 640 by 480.
Of course, many photos can benefit by a bit of cropping, so a smaller well-cropped image can be better!
Contact Us to send us your digital images by E-Mail.
Copyright © 2001 International Opportunities.
All Rights Reserved.|
Site Version 1.75 - Last updated December 20, 2006
This URL: http://www.InterOpp.org/htm/pg_graphics_tp.htm
|Back to Text-only Web Page|