A parade of scandals tarnished the prince’s reputation, long before he gave up using his title as Duke of York on Friday.

© Kirsty Wigglesworth/Associated Press

A consummate showman, he was known for playing guitars rigged with pyrotechnic effects and for his distinctive stage persona.

© Richard Drew/Associated Press

Among the foundations of visual design are two essential insights, into understanding human vision, and the experience gained from our long history of visual communication. Common to both is the importance of tone (brightness, lightness, etc.) and its contrasts. Not only do around one in twenty males struggle to distinguish some or most colours, but all of us rely on tone to interpret what we see in the absence of information from colours.

This has been illustrated throughout the history of visual art, where those who have excelled in visual communication have placed particular emphasis on tone. Consider Lucas Cranach the Elder (1472–1553) as an example of proven classical methods.

We know a lot about the tonal modelling that Cranach used in his Martyrdom of Saint Catherine painted in 1504-5, through the infra-red reflectogram below, which effectively looks through the paint layer at the underdrawing beneath.

Cranach’s assistants first laid a thin layer of light reddish imprimatura on the white ground of this panel. Once that had dried thoroughly, Cranach himself would have laid down the underdrawing using a pointed brush with carbon black ink. This extended to the tonal modelling shown clearly in the reflectogram.

Following that came undermodelling using grey tones of carbon black and lead white. Some of the darker garments were preceded by a local underpainting of black, a technique popular at the time for dark red fabrics in particular. Much of this seems to have been completed quickly, probably within a single day.

A common practice among masters discards colour altogether and builds the image using tone alone, known as grisaille.

Three centuries after Cranach, the great French illustrator and painter Gustave Doré (1832–1883) painted a group of three works about the Franco-Prussian War entirely in grisaille. Best known among those is The Enigma (souvenirs de 1870), from 1871.

Even a few minutes exposure to a screenful of macOS Tahoe’s windows demonstrates how its new design goes out of its way to ignore those essential insights, and present us with controls that are either bleached- or blacked-out depending on our choice of appearance mode.

In light mode, with default transparency, tool icons and text are clearly distinguished tonally, as are some controls including buttons and checkboxes. However, text entry fields are indistinguishable from the background, and there’s a general lack of demarcation, particularly between the controls and the list view below.

Oddly, dark mode outlines some controls better than light mode, but text entry fields and the list view below still lack demarcation.

One popular mitigation to this lack of tonal contrast is to resort to an Accessibility control that purports to reduce transparency rather than increasing contrast, although in fact its main advantage in Tahoe is to improve tonal contrast, at least in the toolbar.

This still has no effect on controls below the toolbar, and fails to demarcate text entry fields or the list view below.

The elephant in macOS Tahoe is its ignorance of human vision and our long experience of visual communication. It’s an elephant that comes in two appearance modes, bleached-out white or blacked-out black. It has little if any impact on the interface of Apple’s other OS 26es, but it makes macOS a pain to look at and harder to use. I feel sure that Lucas Cranach the Elder, Gustave Doré and every other self-respecting visual artist would be equally offended.

MAGA is tearing itself apart over who really killed Charlie Kirk.

If you bought an M1 Mac with just a 256 GB internal SSD and have kept up with macOS upgrades and updates, should you be worried that it’s running out of space by the time it makes it to Tahoe? Dare you look at Storage settings to see how much of the SSD is now swallowed up by System Data? This article explains why macOS 26 shouldn’t devour the last of your SSD, and how you can ensure that it doesn’t.

What’s on your Mac’s internal SSD?

Internal boot disk layout is most complex in Apple silicon Macs, as theirs is divided into three partitions (or APFS containers). Two are hidden and contain pre-boot and other low-level support files, and amount to around 6 GB. The Macintosh HD partition then takes the lion’s share, the whole of the remainder. Even on a 256 GB SSD, that’s about 250 GB.

Volumes within Macintosh HD include:

• System, just over 12 GB,
• VM, varies in size according to how much virtual memory is swapped out to disk,
• Preboot, just under 8 GB,
• Recovery and others not normally mounted, a total of less than 2 GB,
• Data, whose size is determined by what you store there.

The system your Mac actually boots into isn’t the System volume itself, but a snapshot made of it, occupying the same space, plus a little extra for the snapshot’s metadata including its tree of hashes to form its seal and signature. Because this is a snapshot it uses the same data stored for the System volume, and doesn’t double that up.

This should allow your Data volume a maximum of 228 GB, less any space required by the VM volume. Although installation of a macOS upgrade or update will require substantial additional space, once that’s complete the space taken by the System volume and its snapshot should fall to little more than 12 GB.

What happens when macOS is upgraded?

In traditional macOS upgrades, the Installer app was downloaded first, and itself required around 13-15 GB. That was run, and expanded its contents to be installed onto the System volume, replacing much or all of it.

Updates work more economically, as they contain only the files that have changed, so far less than the Installer app. When they’re installed, they replace only those files changed in the System volume, ready for a new snapshot to be made from that, to be used to boot that Mac. So an update-style upgrade, as you should get when going from macOS 15.7 to 26.0, should require a much smaller download, a faster install, and less space to install the new version of macOS. However, the end result should be identical, with exactly the same files installed in the System volume, and exactly the same in the snapshot used when running.

Whichever is used, the installation process is similar. First, the files to be installed are expanded, then they’re written to the mounted System volume, with some going onto the Data volume as well. Once the System volume is complete, a snapshot is made of it, and that’s sealed using a tree hierarchy of hashes, culminating at the top of the tree in the seal.

What is System Data?

Storage settings scans the contents of the boot volume group, Macintosh HD, and divides the storage used into different categories like Applications and Podcasts. It appears to total those up and account for the remainder of storage used in the category System Data. That doesn’t include the size of the System volume, or its snapshot, but can include temporary files like caches, snapshots, and anything else it can’t account for in other categories.

Taking control

If there are substantial amounts of space that aren’t accounted for on your Mac’s internal SSD, and you want to reduce that, you need to account for it before deciding what to do about it.

First check for large snapshots. I hear repeatedly of Macs that turn out to have hundreds of GB being used by snapshots unnecessarily, and the current record is over 400 GB. The easiest place to check for those is in Disk Utility. In the sidebar on the left select the Data volume, then Show APFS Snapshots in the View menu for them to be displayed at the foot of the main view.

Backup utilities including Time Machine normally make a snapshot with each backup, and retain them for 24 hours, following which they’re automatically deleted. As snapshots can’t exclude folders in the way that Time Machine can in its backups, if you’ve been working with a couple of 100 GB VMs then they will be retained in snapshots even though you probably exclude them from being backed up.

Once you’re happy that free space isn’t being retained in snapshots, use a disk mapping utility like DaisyDisk or GrandPerspective to hunt down other large files and folders that you may not need. One reader here recently discovered that their iOS and iPadOS backups had taken over more than half the space on their Mac’s SSD.

Wait a day or two after upgrading

Installing a macOS upgrade also changes files on your Data volume, and may retain temporary support files. These are normally cleaned up in the next 24 hours, and you may be able to encourage that by starting your Mac up in Safe mode, leaving it a couple of minutes, then restarting it in normal user mode.

By a couple of days after the upgrade, your Mac should have returned to normal use of storage. If it hasn’t, check snapshots and go hunt that missing space.

macOS 26 Tahoe’s big thing is its redesigned interface, with additional variations to appearance modes and its new Liquid Glass effects. Whether you’re installing the upgrade because of those, or in spite of them, allow me to take you on a quick tour of how you can set its interface up, and which controls do what.

There are three sets of controls:

• Appearance mode, Light or Dark, in Appearance settings;
• Display variations to Reduce transparency or Increase contrast, in Accessibility settings;
• Icon & widget style, in Appearance settings.

That comes to a total of more than 20 combinations before factoring in icon tinting colour, so there’s no shortage of choice.

Light mode

There are three overall variations of light mode, depending on those Accessibility settings.

The starting point and default is in light mode without Accessibility, and icon & widget style set to Default. Note the effects of transparency on the menu bar, widgets, the Liquid Glass effect in the left side of the Dock, and the upper row of icons in the Finder window. If you like those, you don’t have to change any settings.

This is light mode with Reduce transparency enabled in Accessibility settings. This disables all Liquid Glass effects and restores the traditional menu bar and Dock. The effect on Desktop widgets is perhaps less beneficial.

In light mode with Increase contrast (automatically coupled with Reduce transparency) enabled, the predominant effect is the outlining of controls within each window, rather than any change in contrast. Colours used by the system, such as the traffic light controls at the top left of each window, and those in themes, are darker, but those elsewhere, as in icons, aren’t changed. The effect here is to make controls clearer rather than actually changing contrast.

Dark mode

Without changing Accessibility and leaving Icon & widget style set to Default, dark mode shows transparency and Liquid Glass effects as you expect. These are again most visible in the menu bar, Dock, and the upper row of icons in the Finder window.

With Reduce transparency enabled in Accessibility settings those transparency and Liquid Glass effects are removed.

Enabling Increase contrast outlines controls clearly, but any changes in system colours are more variable than in light mode.

Icon & widget style

This is new to Tahoe and only affects the rendering of icons and widgets.

Using light mode without any Accessibility changes, the Default setting for Icon & widget style is the baseline, showing icons in their ‘normal’ state.

Dark icon settings in light mode contrasts more but their readability may suffer.

When Icon & widget style is set to Clear, most are decolourised, making them significantly harder to read, and impossible to distinguish in the sidebar of System Settings.

The final option is for Icon & widget style to be Tinted, where they’re rendered in monochrome using a colour of your choice, selected from the popup menu below. On iPhones and other devices that are available in several case colours, some have decided to set tinting to match the case, something you might like to try with an Apple silicon iMac, for example.

However, be careful in both Clear and Tinted styles, as it’s easy to end up making many icons unreadable and almost indistinguishable, here by setting the last of those to Graphite colour. This is one of the obvious drawbacks in Tahoe’s flexibility, in that many combinations of appearance mode, Accessibility settings and icon and widget style degrade its human interface rather than enhancing it. At least you now know what not to try, and how to return it to its defaults.

Summary of controls

• Appearance mode, light or dark, in Appearance settings;
• Display variations to Reduce transparency or Increase contrast, in Accessibility settings;
• Icon & widget styles, in Appearance settings, with Icon, widget & folder colour when appropriate.

Have fun!

Unlike Apple’s bundled apps in macOS, the great majority of third-party software needs to run on more than just the latest version of macOS. This is a challenge when there’s a major redesign of the interface, as there is in macOS Tahoe. While OS 26 may bring greater consistency across platforms, it’s also important to developers and users that it doesn’t sacrifice consistency between, say, Sequoia and Tahoe.

As I showed recently in my simple little utility DropSum, at times the appearance of windows can be very different between macOS 15 Sequoia and 26 Tahoe. DropSum uses AppKit rather than SwiftUI, and is a little unusual in applying colour to its window. This is used in a popular mechanism to indicate when that window is ready to receive a file being held over it, by changing the view colour from systemOrange to systemGreen. As that coloured view extends over the controls in the window, I have had to be careful to ensure those controls remain readable in both appearance modes, with the Reduce transparency and Increase contrast settings in Accessibility settings, and across recent versions of macOS. That hasn’t proved easy, so what you see below appears to be the best compromise I can achieve. DropSum doesn’t alter its settings or behaviour between different versions of macOS, instead relies on the host API’s appearance modes and Accessibility settings.

Although I have confirmed the observations below on individual systems, to make comparison easier here each screenshot shows two DropSum windows. The upper is running in a Tahoe beta 7 VM (where the window title is left-aligned), and the lower in Sequoia 15.6.1 on the host (where the window title is centred).

Light mode

In both light appearance modes, all boxed text is displayed in black on a white background, making their contents and controls clear. There are marked differences in the hues seen, though, with both systemOrange and systemIndigo (chosen for better contrast in labels) being more intense in Tahoe than Sequoia. As expected, Tahoe’s controls are slightly larger, and the corners of all four text boxes are rounded rather than square.

Reducing transparency made little difference in either rendering, merely whitening the window title bar.

Increasing contrast changes the intensity of some colours. In Sequoia, systemOrange is lightened, and in both windows the traffic light buttons at the top left, and the Clear button, are darkened. Otherwise the most obvious effect is the outlining of all components, including each of the controls.

Apps built to support macOS 26 thus appear consistent between macOS 15 and 26 when used in light mode.

Dark mode

Most apparent here are the contrasting effects of dark mode on the background of the four text boxes. In Sequoia, their background is the systemOrange of the coloured view, but in Tahoe it’s black. The latter makes the text contents more readable, while unselected text in Sequoia is more difficult to read.

Increasing contrast has different effects on colours when in dark mode. In Sequoia all colours including the systemOrange view become slightly lighter, whereas in Tahoe the contrast of some is enhanced, with black becoming blacker and white whiter, but there’s little discernible change in systemOrange, which remains significantly more intense than in Sequoia. systemIndigo is rendered lighter though, making it more difficult to read against the systemOrange background.

Reduce transparency

Apple describes this effect as replacing “the transparent effect used on some backgrounds in macOS with a solid background to improve contrast and readability.” In both Sequoia and Tahoe, and in both appearance modes, the only effect observed is a lightening of the window title bar, as the rest of the window is already opaque.

Increase contrast

Apple describes this as increasing “the contrast of items on the screen (such as borders around buttons or boxes) without changing the contrast of the screen itself.” Although the borders are the most prominent effect in both versions of macOS and both appearance modes, there are also colour changes that aren’t consistent between Sequoia and Tahoe.

Conclusions

• Appearance modes in Tahoe exhibit different behaviours from those in Sequoia, most markedly in dark mode. In this example, Tahoe has the effect of enhancing readability in dark mode.
• Colour rendering of systemOrange also differs between Tahoe and Sequoia.
• Reduce transparency has little effect other than making transparent views opaque.
• Increase contrast primarily adds black (light mode) or white (dark mode) borders to controls, but its small colour changes, as seen here in Tahoe, may impair readability.
• Designing an interface that behaves consistently in both macOS Tahoe and older versions of macOS is a challenge that may not always work out. Developers need to assess their app’s human interface thoroughly in multiple macOS, appearance modes and Accessibility settings.

The Chinese Consulate in Manhattan has mobilized community groups to defeat candidates who don’t fall in line with the authoritarian state.

As we near the end of Tahoe’s incubation period, and Apple’s engineers code its last fixes and tweaks ready for its launch in just a few weeks, I’d like to reflect on what macOS 26 has to offer beyond its marketing headlines.

While there are several worthwhile new features such as the Phone app, Magnifier, and live translation, there’s nothing to compare with the fundamental changes in recent versions of macOS that brought the SSV, Shortcuts, System Settings and Apple Intelligence. Instead Tahoe is overwhelmingly about its human interface.

Every new design of the Mac’s operating systems that I can recall has elicited outcry from many. Understandably, the majority almost invariably want constancy, the same Finder and app icons that we’ve become so familiar with. It’s only human. It’s also a sure route to what others will condemn as stale, as it hasn’t been refreshed for so many years.

Personally, I don’t like to see a design on my Mac. If I notice it, then it’s a distraction. I’d much prefer to have an interface as clean as the whistles of the late Classic Mac OS period: lean, purposeful and lacking in visual trickery or frippery. But I accept that, without all the adornments and animations, many today would wonder why their Mac needed a GPU. I confess that I was never a fan of the original Aqua interface either. Given that its declared goal was to “incorporate colour, depth, translucence, and complex textures into a visually appealing interface”, I wonder whether much the same could be said of Tahoe.

Perhaps the most striking feature of this redesign is its lack of contrast between elements and tools in window controls and their contents, whether its appearance is set to light or dark mode, or one of its new in-between variants. You can see this clearly in most screenshots of Tahoe, such as those posted by Apple, and as far as I can see it hasn’t improved during beta-testing. This is also universal, and isn’t confined to apps using the more novel SwiftUI, although I have to keep pinching my thigh to remind myself that SwiftUI is now six years old, only two years younger than APFS. The contrast in stability and maturity between the two couldn’t be greater.

You can of course ‘improve’ contrast by enabling Reduce Transparency in Accessibility settings, but in doing so you lose most if not all of Tahoe’s Liquid Glass effects, as they depend on the transparency you’ve just turned off.

Transparency is a good example of design being given priority over readability or content. Because the appearance of the upper layer containing controls or content depends on what is underneath, it’s down to chance whether the greyed text you’re struggling to read happens to be over a background that further reduces its contrast. In the worst case, you could find yourself having to move a window so you can read part of it clearly, not a sign of a good human interface.

My other major concern with Tahoe’s new look is that it seems not to recognise the differences between Macs, iPads and iPhones, in terms of displays, input controls, and apps. Rather than sameness, I’d much rather have consistency that recognises the difference between manipulating Xcode’s compound windows containing dense structured text on a 27-inch display, and checking a family photo filling the 6.1-inch display of an iPhone.

One of my favourite controls in macOS is the Combo Box, a versatile and elegant hybrid of the popup/dropdown/pulldown menu/button and a text entry box. I can’t recall seeing one used in iOS, as it would be clumsy and inappropriate. It’s well supported for macOS in AppKit but hasn’t yet been implemented in SwiftUI. If controls are going to be common across all Apple’s operating systems, then macOS is about to lose one of its best.

It seemed only appropriate that, in the weeks before Apple releases OS 26 across Macs and devices, Tim Cook should go to the White House to pay its corporate tribute in a block of materialised Liquid Glass mounted on pure bling. But the image that I keep thinking of in fear, is that of Elon Musk demonstrating the resilience of his Cybertruck’s window by throwing a metal ball at it, in November 2019. I just hope Tahoe’s Liquid Glass doesn’t go the same way.

这周末（周五到周一）是复活节假期。本来只想在本地走走，不过星期天早上起来发现本地天气预报多云，伦敦反而晴到多云 […]

上周六（4月5日）伦敦格林威治公园（Greenwich Park）的樱花才刚刚开始，大多还是花骨朵。这周末我估 […]