Underwater photos are the main asset of most dive centres, more than their copy, their prices or their logo. A good shot of a manta or a nudibranch persuades more effectively than any paragraph.
Yet almost all of these photos are invisible to Google. They are named DSC0045.jpg, have no description and weigh five megabytes each, because they go straight from the camera to the website. A gallery page with forty such photos takes a very long time to load on a 3G connection, which is what many travellers use when looking up your business.
A manta ray photo has no value to Google if it is named DSC0045.jpg. The fix is mostly methodical, and inexpensive.
Why name image files in words rather than DSC0045?
This is the simplest fix in all of SEO, and almost everyone overlooks it.
Before uploading a photo, rename it with a few plain words describing its content, separated by hyphens: manta-ray-cleaning-station-nusa-penida.jpg, open-water-course-pool-session.jpg, beach-bungalow-sunrise.jpg.
According to Google, file names give it a small hint about what an image shows. The effect is modest, but the step is free, takes ten seconds and will also help you find your own photos a year from now.
Avoid overloading the name. best-dive-bali-cheap-dive-course-bali-manta.jpg helps nobody and looks like spam. Simply describe the photo.
How should alt text be written?
For a person who cannot see the photo. Alt text is the short description embedded in the HTML behind an image. Most people treat it as an SEO device and fill it with keywords: "Bali diving Bali dive centre best diving Bali."
That approach is mistaken. Alt text exists for people who cannot see the image: someone using a screen reader, or someone whose connection is so slow the image never loaded. For them, the words replace the picture.
Write it for them, then. How would you describe the photo out loud to someone on the phone?
- Avoid: "diving"
- Avoid: "Bali diving best dive centre Bali manta"
- Prefer: "A manta ray gliding over a cleaning station, with two divers watching from the reef below"
What helps a blind reader also helps Google, which is also trying to understand what is in the picture. There is no need to choose.
A few details. Purely decorative images, such as a background texture or a divider line, can have empty alt text so screen readers skip them. Avoid starting with "image of" or "photo of", because the screen reader already announces that it is an image. If the image is a link, describe where the link leads.
What role do captions and surrounding text play?
Google does not read only the alt text. It considers the caption, the heading above and the adjacent paragraph. A photo of a turtle on a page about turtle encounters, with a caption stating where and when, is much easier to interpret than the same photo isolated in a gallery. Place your best photos where the text already is.
Why compress every image before uploading?
The problem is growing this year. Apple introduced a Retina screen on the new iPad in March and on a MacBook Pro in June, and designers now want images twice as large so they look sharp on those screens. Meanwhile, half your visitors are on a phone somewhere with two bars of signal.
Google has used site speed as a minor ranking signal since 2010. Its weight is limited, but a slow page loses visitors before Google even comes into play, and on a photo-heavy site, the images are almost always what slows the page down.
Here are the steps to take:
- Resize before uploading. No web page requires a 4000-pixel-wide image. Around 1200 to 1600 pixels on the long side is enough for a large photo on most screens, and the main header image can be larger if you want it crisp on a Retina display.
- Compress. A good photo should weigh a few hundred kilobytes, not several megabytes. Photoshop's "Save for Web" function does this, and free tools such as Yahoo's Smush.it reduce the size further. A WordPress plugin for Smush.it is also available.
- Load images further down the page only when the visitor reaches them. Lazy-loading scripts and WordPress plugins provide this function, which is very useful for long galleries.
- Watch the WebP format, announced by Google in 2010. Only Chrome and Opera genuinely support it for now, so JPEG remains the everyday choice. The format is nonetheless worth following.
Serving a smaller image to phones and a larger one to big screens is a problem without a satisfactory solution yet. Browser makers and web developers are currently debating the approach, with a proposed picture element on one side and a srcset attribute on the other. Until a standard emerges, keep your images reasonably sized and avoid letting a single heavy photo slow down the whole page.
Some of these steps are simple. Others depend on how your theme and hosting are configured. If your site is slow for no apparent reason, a technical SEO review usually identifies the images first.
What does Google recommend regarding images?
Google is giving images an increasingly prominent role. It is already possible to search by image, dropping a photo into Google Images to find where else it appears or what it shows. That is a good reason to use your own photos, and a good way to find out who is using yours.
The basics Google asks for are simple: use real, original images, place them near relevant text, give them good file names and alt text, and make the page fast. Google's guidelines for publishing images essentially set out these principles, in more detail, and are worth reading.
Why are your own photos preferable to stock images?
This is a recommendation based on our experience.
Dive sites all seem to use the same few whale shark pictures, bought from the same stock agencies. The rest of the tourism sector does the same with smiling couples on beaches. Google knows these images appear on hundreds of sites, and your visitors sense it too.
Real photos of your place, your food and your guests who agreed to appear in them are the one type of content no one can copy. A slightly blurry photo of your actual dining room is more effective than a perfect stock image, because it is authentic.
Take the photos, then spend ten minutes per batch renaming, describing and reducing them. Almost no one does, and that is largely what makes the practice effective.