Time Exposure Classics September 17, 2002 admin
Using Free Photo Hosting Services
Together With TZ.
Posted by Frank N. on November 23, 2001 at 01:40:54:
TZ Classics Forum Number: 1856
Posted from Host: (184.108.40.206)
When people new to posting photographs try out their craft on one of the TZ fora, there is one trap that they almost invariably fall into before being told about it: Free web hosting sites rules against external linking.
External linking is simply what you do, when you make a reference to a photograph on, say Geocities, from within a post on TZ. Ie. from the view of the server hosting the photo, the link is from an ‘outside’ source.
Most free web hosting services rely on advertising and similar means of earning what they need to stay in business, while giving away space and bandwidth to their ad viewing customers. Thus they have to ensure that they actually do get eyeballs to look at their pages, which then contains their customers photographs in addition to the ads.
Having someone use their services for hosting photographs, which will not be associated with actual views of their ads are just a waste of resources, as far as they are concerned. Thus they actively disallow this practice by programming the server not to give out a requested photograph, unless the page referring the image is from an ‘allowed’ site, like themselves.
Transparently to the users most web browsers gives out a referral page identifier, when they request another page or image from a server. This is how the free web space providers server knows how not to serve images for web pages on TZ, Eprey and most other sites on the planet. Some rare breeds of web browser programs can be told not to give out such referral information, but they are not in general use at this time.
How come I myself am able to see my photographs in the TZ posting preview, while the rest of the world isn’t?
Simple. In order to save network bandwidth all web browsers have a local cache of recently downloaded material on the local harddisk. Whenever a new page or imagery is requested by the user, the browser checks if it already has a local copy of what is requested. If it does, then the local copy is shown in place of a freshly downloaded copy. Thus no new request is actually sent anywhere, in particular to the free web space hosting service.
Chances are better than very good that you have just uploaded your nice watch photographs to the web host a few minutes before making a post using them on TZ. Thus you have previewed your free web pages, including the photographs, and have them in your local disk cache.
When you do a posting preview, the browser already knows about the photograph(s) in question, and silently shows the local copy. You post looks perfect and you press ‘Post Message’.
Everyone else have not seen your photos before, and their browsers try to download them from the free web hosting service, using the TZ page as referral. *Crunch* Broken image icons galore.
Insiders trick: Some web browsers, Netscape in particular, allows you to right click on a broken image icon and then selecting ‘View Image’. This will cause the browser to attempt to download the image in a new window, using an empty(!) referral page string. This usually works, and once the photo is loaded, you may go ‘Back’ and see the posters work in all its splendor.
Morale: Check the free photo host’s policy re. external linking before attempting to use imagery from it off site.