Galleries are a quick — but limited — way to display a number of images on a single page. In general, they should be avoided on this wiki. It is much preferred that individual images accompany blocks of text. However, they are acceptable in some situations, such as when displaying a series of covers. In some other cases, they are outright forbidden.
Points to ponder
Wikia's explanation of galleries will tell you the simplest way to make a gallery. But it won't tell you much about how the function behaves in live examples. That's why we're providing some wisdom from actual case studies.
Always hide the add photo button. If you don't add any options to your <gallery> tag, it will automatically show a button that invites users to add a photo the gallery. This is undesirable for several reasons:
- It makes it easy for vandals or even just new users testing the wiki to ruin your gallery. With a couple of clicks, they can easily insert inappropriate images directly into your gallery.
- It allows people to upload images without adding a proper copyright license. The add button completely bypasses the Licensing drop-down menu presented when you upload a file.
- It makes the end of a particular gallery obvious. If you remove the button, you can put several galleries together in such a way that the join isn't obvious (so long as you haven't put a border around your galleries).
For these reasons, this wiki requires you to hide the add button by using this markup:
Enough is enough
Don't go overboard with galleries. Theoretically, you can use galleries to display a very large number of images. This poses a problem for users who have slow connections. We're not just talking about those who use dialup. We mean almost everyone who's viewing on a smartphone, and many who are connected wirelessly.
Don't assume that everyone has a computer, or internet connection, as good as yours.
To help with this problem:
- Use .jpg files only. Other file types are either unscalable (which is vital to galleries) or far too high-quality for the purpose of galleries.
- Reduce the file-size of your gallery images to around or below 50kb. Certainly, don't go over 100kb with any one image. You can reduce your filesize most easily in Photoshop by saving for web (as opposed to normally saving), and dialing down the quality to around 20. Make the filesize of every image as small as you possibly can.
- Find a way to limit the total number of images in a single gallery structure. Do you really need all 200+ images of, say, Doctor Who Adventures covers on a single page? Or can you create a page for each publication year?
Watch your dimensionsKeep the dimensions of your images as equal as possible. The gallery function basically creates a series of thumbnails. But it's not like this kind of thumbnail:
[[file:Pic.jpg|thumb]]No, the gallery thumbnail creates relative thumbnails. It considers all the images in the gallery and resizes them relative to each other, trying to put them into the specified width. (If you don't specify a width, it defaults to 200px.)
This can produce some highly unexpected results if you're trying to create a gallery of images with radically different dimensions.
- the ratio of width to height
A image that is 800X400 has the same dimensions as one that is 400X200 —
but not one that's 137X877.
Technically, there's always some level of distortion in a gallery, if the pics don't have the exact same dimension. But it is considerably less obvious if the files are all of the same dimensions.
Putting a lot of images of widely divergent dimensions in the same gallery often results in "warping" or "stretching" of some of the images.
To help with this problem:
- Try to use images that are all of the same dimensions. If you're displaying a series of magazine covers, for instance, it's a good idea to crop all of them to precisely the same dimensions. That way, they'll all be perfectly scaled down.
- If you must use a mixture of widescreen, 4:3, and extremely skinny images, don't put them all into the same gallery structure. Find a way to break up the galleries on the same page, so that the gallery command is not having to work so hard.
Rules of use
There are a few absolute rules which should be observed when using galleries. Failure to observe these rules could lead to a suspension of your editing rights:
- Never use a gallery for a single image. Single images should be placed on pages using the syntax:
[[file:PicName.extension]]as described at Help:Files. There is simply no advantage to using the gallery structure for a single image; the wikitext for file display is invariably superior for the task.
- Always hide the add button. All galleries must begin with a command that looks like this:
- Never use galleries on in-universe pages.
- Use caution with galleries on story pages. Generally, they should be used only when displaying a series of alternate covers. There is no other reasonable usage for galleries on story pages. No story page should have a gallery of images from that story.