Tags: images

It’s often said that it’s easier to make a fast website than it is to keep a website fast. Things slip through. If you’re not vigilant, performance can erode without you noticing.

It’s a similar story for other invisible but important facets of your website: privacy, security, accessibility. Because they’re hidden from view, you won’t be able to see if there’s a regression.

That’s why it’s a good idea to have regular audits for performance, privacy, security, and accessibility.

I wrote about accessibility testing a while back, and how there’s quite a bit that you can do for yourself before calling in an expert to look at the really gnarly stuff:

When you commission an accessibility audit, you want to make sure you’re getting the most out of it. Don’t squander it on issues that you can catch and fix yourself. Make sure that the bulk of the audit is being spent on the specific issues that are unique to your site.

I recently did an internal audit of the Clearleft website. After writing up the report, I also did a lunch’n’learn to share my methodology. I wanted to show that there’s some low-hanging fruit that pretty much anyone can catch.

To start with, there’s keyboard navigation. Put your mouse and trackpad to one side and use the tab key to navigate around.

Caveat: depending on what browser you’re using, you might need to update some preferences for keyboard navigation to work on links. If you’re using Safari, go to “Preferences”, then “Advanced”, and tick “Press Tab to highlight each item on a web page.”

Tab around and find out. You should see some nice chunky :focus-visible styles on links and form fields.

Here’s something else that anyone can do: zoom in. Increase the magnification to 200%. Everything should scale proportionally. How about 500%? You’ll probably see a mobile-friendly layout. That’s fine. As long as nothing is broken or overlapping, you’re good.

At this point, I reach for some tools. I’ve got some bookmarklets that do similar things: tota11y and ANDI. They both examine the source HTML and CSS to generate reports on structure, headings, images, forms, and so on.

These tools are really useful, but you need to be able to interpret the results. For example, a tool can tell you if an image has no alt text. But it can’t tell you if an image has good or bad alt text.

Likewise, these tools are great for catching colour-contrast issues. But there’s a big difference between a colour-contrast issue on the body copy compared to a colour-contrast issue on one unimportant page element.

I think that demonstrates the most important aspect of any audit: prioritisation.

Finding out that you have accessibility issues isn’t that useful if they’re all presented as an undifferentiated list. What you really need to know are which issues are the most important to fix.

By the way, I really like the way that the Gov.uk team prioritises accessibility concerns:

The team puts accessibility concerns in 2 categories:

1. Theoretical: A question or statement regarding the accessibility of an implementation within the Design System without evidence of real-world impact.
2. Evidenced: Sharing new research, data or evidence showing that an implementation within the Design System could cause barriers for disabled people.

The team will usually prioritise evidenced issues and queries over theoretical ones.

When I wrote up my audit for the Clearleft website, I structured it in order of priority. The most important things to fix are at the start of the audit. I also used a simple scale for classifying the severity of issues: low, medium, and high priority.

Thankfully there were no high-priority issues. There were a couple of medium-priority issues. There were plenty of low-priority issues. That’s okay. That’s a pretty good distribution.

If you’re interested, here’s the report I delivered…

Accessibility audit on clearleft.com

Colour contrast

There are a few issues with the pink colour. When it’s used on a grey background, or when it’s used as a background colour for white text, the colour contrast isn’t high enough.

The SVG arrow icon could be improved too.

Recommendations

Medium priority

• Change the pink colour universally to be darker. The custom property --red is currently rgb(234, 33, 90). Change it to rgb(210, 20, 73) (thanks, James!)

Low priority

• The SVG arrow icon currently uses currentColor. Consider hardcoding solid black (or a very, very dark grey) instead.

Images

Alt text is improving on the site. There’s reasonable alt text at the top level pages and the first screen’s worth of case studies and blog posts. I made a sweep through these pages a while back to improve the alt text but I haven’t done older blog posts and case studies.

Recommendations

Medium priority

• Make a sweep of older blog posts and case studies and fix alt text.

Low priority

• Images on the contact page have alt text that starts with “A photo of…” — this is redundant and can be removed.

Headings

The site is using headings sensibly. Sometimes the nesting of headings isn’t perfect, but this is a low priority issue. For example, on the contact page there’s an h1 followed by two h3s. In theory this isn’t correct. In practice (for screen reader users) it’s not an issue.

Recommendations

Low priority

• On the home page, “UX London 2023” should probably be h3 instead of h1.
• On the case studies index page we’re currently using h3 headings for the industry sector (“Charities”, “Education” etc.) but these should probably not be headings at all. On the blog index page we use a class “Tags” for a similar purpose. Consider reusing that pattern on the case studies index page.
• On the about index page, “We’re driven to be” is an h3 and the subsequent three headings are h2s. Ideally this would be reversed: a single h2 followed by three h3s.

Link text

Sometimes the same text is used for different links.

Recommendations

Low priority

• On the home page the text “Read the case study” is re-used for multiple links. It would be better if each link were different e.g. “Read about The Natural History Museum.”

Forms

The only form on the site is the newsletter sign-up form. It’s marked up pretty well: the input has an associated label, although a visible (clickable) label would be better.

Tabbing order

The site doesn’t use JavaScript to mess with tabbing order for keyboard users. The source order of elements in the markup generally makes sense so all is good.

The focus styles are nice and clear too!

Structure

The site is using HTML landmark elements sensibly (header, nav, main, footer, etc.).

I’m standing on a huge stage in a giant hangar-like room already filled with at least a thousand people. More are arriving. I’m due to start speaking in a few minutes. But there’s a problem with my laptop. It connects to the external screen, then disconnects, then connects, then disconnects. The technicians are on the stage with me, quickly swapping out adaptors and cables as they try to figure out a fix.

This is a pretty standard stress dream for me. Except this wasn’t a dream. This was happening for real at the giant We Are Developers World Congress in Berlin last week.

In the run-up to the event, the organisers had sent out emails about providing my slide deck ahead of time so it could go on a shared machine. I understand why this makes life easier for the people running the event, but it can be a red flag for speakers. It’s never quite the same as presenting from your own laptop with its familiar layout of the presentation display in Keynote.

Fortunately the organisers also said that I could present from my own laptop if I wanted to so that’s what I opted for.

One week before the talk in Berlin I was in Amsterdam for CSS Day. During a break between talks I was catching up with Michelle. We ended up swapping conference horror stories around technical issues (prompted by some of our fellow speakers having issues with Keynote on the brand new M1 laptops).

Michelle told me about a situation where she was supposed to be presenting from her own laptop, but because of last-minute technical issues, all the talks were being transferred to a single computer via USB sticks.

“But the fonts!” I said. “Yes”, Michelle responded. Even though she had put the fonts on the USB stick, things got muddled in the rush. If you open the Keynote file before installing the fonts, Keynote will perform font substitution and then it’s too late. This is exactly what happened with Michelle’s code examples, messing them up.

“You know”, I said, “I was thinking about having a back-up version of my talks that’s made entirely out of images—export every slide as an image, then make a new deck by importing all those images.”

“I’ve done that”, said Michelle. “But there isn’t a quick way to do it.”

I was still thinking about our conversation when I was on the Eurostar train back to England. I had plenty of time to kill with spotty internet connectivity. And that huge Berlin event was less than a week away.

I opened up the Keynote file of the Berlin presentation. I selected File, Export to, Images.

Then I created a new blank deck ready for the painstaking work that Michelle had warned me about. I figured I’d have to drag in each image individually. The presentation had 89 slides.

But I thought it was worth trying a shortcut first. I selected all of the images in Finder. Then I dragged them over to the far left column in Keynote, the one that shows the thumbnails of all the slides.

It worked!

Each image was now its own slide. I selected all 89 slides and applied my standard transition: a one second dissolve.

That was pretty much it. I now had a version of my talk that had no fonts whatsoever.

If you’re going to try this, it works best if don’t have too many transitions within slides. Like, let’s say you’ve got three words that you introduce—by clicking—one by one. You could have one slide with all three words, each one with its own build effect. But the other option is to have three slides: each one like the previous slide but with one more word added. If you use that second technique, then the exporting and importing will work smoothly.

Oh, and if you have lots and lots of notes, you’ll have to manually copy them over. My notes tend to be fairly minimal—a few prompts and the occasional time check (notes that say “5 minutes” or “10 minutes” so I can guage how my pacing is going).

Back to that stage in Berlin. The clock is ticking. My laptop is misbehaving.

One of the other speakers who will be on later in the day was hoping to test his laptop too. It’s Håkon. His presentation includes in-browser demos that won’t work on a shared machine. But he doesn’t get a chance to test his laptop just yet—my little emergency has taken precedent.

“Luckily”, I tell him, “I’ve got a backup of my presentation that’s just images to avoid any font issues.” He points out the irony: we spent years battling against the practice of text-as-images on the web and now here we are using that technique once again.

My laptop continues to misbehave. It connects, it disconnects, connects, disconnects. We’re going to have to run the presentation from the house machine. I’m handed a USB stick. I put my images-only version of the talk on there. I’m handed a clicker (I can’t use my own clicker with the house machine). I’m quickly ushered backstage while the MC announces my talk, a few minutes behind schedule.

It works. It feels a little strange not being able to look at my own laptop, but the on-stage monitors have the presentation display including my notes. The unfamiliar clicker feels awkward but hopefully nobody notices. I deliver my talk and it seems to go over well.

I think I’ll be making image-only versions of all my talks from now on. Hopefully I won’t ever need them, but just knowing that the backup is there is reassuring.

Mind you, if you’re the kind of person who likes to fiddle with your slides right up until the moment of presenting, then this technique won’t be very useful for you. But for me, not being able to fiddle with my slides after a certain point is a feature, not a bug.

I made the website for this year’s UX London by hand.

Well, that’s not entirely true. There’s exactly one build tool involved. I’m using Sergey to include global elements—the header and footer—something that’s still not possible in HTML.

So it’s minium viable static site generation rather than actual static files. It’s still very hands-on though and I enjoy that a lot; editing HTML and CSS directly without intermediary tools.

When I update the site, it’s usually to add a new speaker to the line-up (well, not any more now that the line up is complete). That involves marking up their bio and talk description. I also create a couple of different sized versions of their headshot to use with srcset. And of course I write an alt attribute to accompany that image.

By the way, Jake has an excellent article on writing alt text that uses the specific example of a conference site. It raises some very thought-provoking questions.

I enjoy writing alt text. I recently described how I updated my posting interface here on my own site to put a textarea for alt text front and centre for my notes with photos. Since then I’ve been enjoying the creative challenge of writing useful—but also evocative—alt text.

Some recent examples:

• Time to go play some songs with @SalterCane.

  A close-up of a microphone in a practice room. In the background, a guitar player tunes up and a bass player waits to start.

• Brighton in the sun.

  People sitting around in the dappled sunshine on the green grass in a park with the distinctive Indian-inspired architecture of the Brighton Pavilion in the background, all under a clear blue sky.

• Duck leg on white beans with sage, garlic, rosemary and olives.

  Looking down on the crispy browned duck leg contrasting with the white beans, all with pieces of green fried herbs scattered throughout.

But when I was writing the alt text for the headshots on the UX London site, I started to feel a little disheartened. The more speakers were added to the line-up, the more I felt like I was repeating myself with the alt text. After a while they all seemed to be some variation on “This person looking at the camera, smiling” with maybe some detail on their hair or clothing.

• Videha Sharma

  The beaming bearded face of Videha standing in front of the beautiful landscape of a riverbank.

• Candi Williams

  Candi working on her laptop, looking at the camera with a smile.

• Emma Parnell

  Emma smiling against a yellow background. She’s wearing glasses and has long straight hair.

• John Bevan

  A monochrome portrait of John with a wry smile on his face, wearing a black turtleneck in the clichéd design tradition.

• Laura Yarrow

  Laura smiling, wearing a chartreuse coloured top.

• Adekunle Oduye

  A profile shot of Adekunle wearing a jacket and baseball cap standing outside.

The more speakers were added to the line-up, the harder I found it not to repeat myself. I wondered if this was all going to sound very same-y to anyone hearing them read aloud.

But then I realised, “Wait …these are kind of same-y images.”

By the very nature of the images—headshots of speakers—there wasn’t ever going to be that much visual variation. The experience of a sighted person looking at a page full of speakers is that after a while the images kind of blend together. So if the alt text also starts to sound a bit repetitive after a while, maybe that’s not such a bad thing. A screen reader user would be getting an equivalent experience.

That doesn’t mean it’s okay to have the same alt text for each image—they are all still different. But after I had that realisation I stopped being too hard on myself if I couldn’t come up with a completely new and original way to write the alt text.

And, I remind myself, writing alt text is like any other kind of writing. The more you do it, the better you get.

I added a “notes” section to this website eight years ago. I set it up so that notes could be syndicated to Twitter. Ever since then, that’s the only way I post to Twitter.

A few months later I added photos to my notes. Again, this would get syndicated to Twitter.

Something’s bothered me for a long time though. I initially thought that if I posted a photo, then the accompanying text would serve as a decription of the image. It could effectively act as the alt text for the image, I thought. But in practice it didn’t work out that way. The text was often a commentary on the image, which isn’t the same as a description of the contents.

I needed a way to store alt text for images. To make it more complicated, it was possible for one note to have multiple images. So even though a note was one line in my database, I somehow needed a separate string of text with the description of each image in a single note.

I eventually settled on using the file system instead of the database. The images themselves are stored in separate folders, so I figured I could have an accompanying alt.txt file in each folder.

Take this note from yesterday as an example. Different sizes of the image are stored in the folder /images/uploaded/19077. Here’s a small version of the image and here’s the original. In that same folder is the alt text.

This means I’m reading a file every time I need the alt text instead of reading from a database, which probably isn’t the most performant way of doing it, but it seems to be working okay.

Here’s another example:

• the original image,
• the alt.txt file, and
• the note itself.

In order to add the alt text to the image, I needed to update my posting interface. By default it’s a little textarea, followed by a file upload input, followed by a toggle (a checkbox under the hood) to choose whether or not to syndicate the note to Twitter.

The interface now updates automatically as soon as I use that input type="file" to choose any images for the note. Using the FileReader API, I show a preview of the selected images right after the file input.

Here’s the code if you ever need to do something similar. I’ve abstracted it somewhat in that gist—you should be able to drop it into any page that includes input type="file" accept="image/*" and it will automatically generate the previews.

I was pleasantly surprised at how easy this was. The FileReader API worked just as expected without any gotchas. I think I always assumed that this would be quite complex to do because once upon a time, it was quite complex (or impossible) to do. But now it’s wonderfully straightforward. Story of the web.

My own version of the script does a little bit more; it also generates another little textarea right after each image preview, which is where I write the accompanying alt text.

I’ve also updated my server-side script that handles the syndication to Twitter. I’m using the /media/metadata/create method to provide the alt text. But for some reason it’s not working. I can’t figure out why. I’ll keep working on it.

In the meantime, if you’re looking at an image I’ve posted on Twitter and you’re judging me for its lack of alt text, my apologies. But each tweet of mine includes a link back to the original note on this site and you will most definitely find the alt text for the image there.