Howto - Crosslinking descriptions
Published: 28 November 2008
Just avoiding the implicit reference to an anonymous other picture wouldn't help - it's good and relevant information that there is a similar shot from just down the road, but we need to know how to find it. The solution is to cross-link descriptions.
The video to the left shows how this can be done (click the symbol with the four little arrows in the video menu bar to view it in full screen), and the text below gives some more details about how it works.
|These two pictures of Rhosydd quarry in the Moelwynion could do with a link: the text of the picture of the quarry buildings already refers to the hole in the ground shown in the other one, and vice versa.|
| Fig.1: Main picture page.|
Fig.2: Ticket page.
|To crosslink the two images, fire up two browser tabs (or windows), one for each main picture page: buildings, shaft (The changes have been applied on these two images already as I've made the links when writing this article.). Click the Picture details need updating link (cf. Fig.1) under the photograph of the buildings. That will take you to the ticket page for that picture.|
The ticket page (Fig.2) shows the picture and description as it currently is, the ticket history ('Change Requests') and a form with entry fields for the various pieces of information that are normally supplied during the submission of a picture, such as subject and camera grid reference, view direction, date taken, title and description. The description box (arrow 1 in Fig.2) contains the current description, which can be edited: Copy the URL (web address) of the picture to be linked from the main picture page showing the hole in the ground (double click address bar and Ctrl-c works in many browsers)... ...and paste (usually Ctrl-v) it into a sensible place in the existing description: Note that there must be a space after the URL, even if punctuation follows - otherwise the punctuation is interpreted as part of the web address, resulting in a broken link.
Alternatively, just copy the picture ID, i.e. the number at the end of the web address of the picture that is to be linked and place it between double square brackets: This will produce a link with the grid square and title of the linked data set spelled out.
When all links are added, go to the ticket comment box at the bottom of the page (arrow 2 in Fig.2) and say what you've done ('link added' is sufficient in this case); this will be stored in the ticket history of the data set. Finally, hit the Submit changes button (arrow 3 in Fig.2) to commit the changes. This will take you back to an updated version of the main picture page. The description now looks like in Fig.3 below. I've used both link formats for illustration, but of course either of them will do.
Fig.3: Updated description, using both link formats for illustration.
All that's left to do now is the reciprocal link. Use the same procedure to link the quarry buildings from the hole in the ground. As a result, a site visitor can see immediately that these two pictures belong together and can navigate seamlessly between the two.
Pasting in URL's works also for links to other websites than Geograph. This is useful if a link can be supplied to more detailed information on an external site. However, a short note about what kind of information the link provides would be useful in case the target is ever removed.
From the point of view of usefulness of the site to a visitor, it would be good to have such pictures crosslinked as well, i.e. if links between related pictures by different contributors go both ways. If you add a link from someone else's description to your own picture, the procedure is the same as above, but the change is, like all changes to other people's data sets, subject to moderation. This includes an opportunity for the contributor of the other picture to object to the change, which will usually be respected. So, if you'd like to crosslink your pictures with someone else's, try one first and see how they react. If they're positive about it, do some more, and always create the link from your own to the other person's picture first.
- Link from one picture to the next in the order you want, with a back link to the first picture in the sequence. Simon Carey's Tour of Brighton uses this mechanism.
- Go to the Advanced Search and fill in the form such that the search result contains exactly the pictures you want to include. For example, to match all the pictures from your day trip, select yourself under Contributor and put the date when you took the images in both date fields in the Taken line. Select Order by date submitted and hit Find. Searches have unique identifiers, e.g. this one, a walk I did in Cwm Elan on 1 Nov 08, is number 4466058. Use the URL of the search result as a link in your descriptions, and a site visitor can follow your trip step by step.
- Of course, any other searches can also be used, including ones which can still expand due to new submissions. If your picture shows a wind power station, you could provide a link to a search for 'wind farms', where new submissions matching the search will automatically be included in the results.
- If it's difficult to define a search that gives the right results, you can hand pick the images you want using the Mark link in the top right corner of each main picture page. Then go to the Simple Search page, go to the Marked Images box below the list of recent searches, and click the View as Search Results link to convert your marked list into a personalised search with a unique ID number, which you can link as above.
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