Guidelines for Preparing Pictures for Viewing on the Web
(On an electronic screen: monitor, t.v., or projected image)
4 basic guidelines
- Rule of 72 (CRT; but 96px on lcds)
- 3 inch maximum
- File size maximum set by Internet Service Provider
- Email box size limit set by Internet Service Provider
Even a broadband or more than broadband (e.g. T-1) connection to the internet has to abide by these four guidelines unless you send the larger files to be hosted in your ftp folder on your web site.
A picture saved at 72 dpi or 96 dpi - better for LCD monitors - appears to be the same as one saved at 300, 600, 1200, or more dpi when viewed on an electronic screen such as a computer monitor, television (unless the television is high definition or high definition monitor) or as a projector's image. The reason for this is that the screens most of us use don't have an output capable of these high resolutions.
Use the imaging software you have access to to "step-down" or "re-sample" the your image to no higher than 96 dpi.
Image editing software does this in 1 of 2 ways.
- Option of a "wizard" to help you step through the process of "saving for the web." (See saving your jpeg file.)
- Or, look for the editing routines that may go by any of the following terms: resizing (image not canvas), resampling, etc.
File size for your picture is also determined by the size/dimensions of the picture. (This is true when working with it in an image editor. Using the "sizing" handles - the little boxes at the corners and at the mid points of the border of the picture - when you have inserted the picture into a web page or word document will not work. This reduces what you see, but the size of the file stays the same.)
Crop (cut off) as much of the picture as possible without reducing perspective and context. This alone may significantly reduce the file size of your picture without loosing resolution quality. This will also enlarge the face(s) of the person(s) in your image.
Maintain a minimum size for detail of the image you want to keep. guideline is that persons' faces need to be at least the size of a dime.
I recommend 3 inches as being the maximum for the longest side of your picture. (This is enough for 4.5 faces next to each other.) The size you choose is up to you, but remember: the larger the dimensions of your picture, the larger the size. I usually try to get down to maximum of 2 inches for web postings.
Internet Service Providers will often set limits on size of files that will be permitted to be uploaded by you (your ISP) and/or be permitted to be downloaded by your recipient (your receiver's ISP).
Full-sized images that are not processed before sending them (especially those from high megapixel cameras used in "highest quality" mode) many times will exceed these limitations. You will get a "timed-out" or other message that tells you the image/picture file is being blocked.
Posting a large image file to your web page? (Suggestions)
- Your website hosting service has built in limits to the amount (quota) of space you are alotted for your site. Large image files soon fill this up.
- If you are able to post such a large image file on your web site, your viewers may not appreciate waiting for it - especially if they are using a 28.8K or even 56K dial-up connection or a slow DSL.
Let your Christ-centered ethic be your guide when you send an email with picture(s) embedded within the text or sent attached to the email you are sending. When we consider the recipient we will be more aware that ours is not the only email that the person is receiving. And we will take steps necessary (such as preparing our images/pictures for the web) to make sure that others have a chance to send their messages, that may very well be even more pressing - dare I suggest "more important" - than ours.
Another safe-guard that Internet Service Providers provide for their clients is a maximum on the amount of space in the clients' mailboxes. This is to make sure that the ISP can keep their email service to their clients up and running by controlling how much is put on the server and by lessening the chance that their clients' computers will be overwhelmed by too much downloaded when the clients click on "receive mail."