Where the dates come from

Every month heading, every position in the grid and every label under a thumbnail comes from one date per file. Which date that is depends on what the file knows about itself.

Two different questions

“When was this made?” and “when did this file last change?” are not the same question, and AssetScout can group the grid by either. The button with the two rows of squares in the titlebar chooses:

• Creation Date — when the content was made. This is what the app starts with, because it is what the app is for.
• Last Modified — when the file was last written. The answer to “what was I working on last week”: a document edited on Tuesday, a picture exported again this morning.

The button is coloured while the grid is grouped by the modification date, so a surprising order always has a visible cause. Your choice is remembered for the next time you open the app.

The capture date

For a photograph, AssetScout reads the date out of the picture itself. It looks for the EXIF original date first — the moment the shutter was pressed — and falls back to the EXIF digitized date, which is the same value on a digital camera but differs on a scan of an old print. Files that carry neither, which tends to mean older files and some scanners, are asked for their TIFF date instead.

For a video, the date comes from the movie's own creation date, read through AVFoundation.

This is why a folder copied off a camera last week still falls into the months the pictures were taken in. The file was created last week; the photograph was not.

When there is no capture date

Sound files, text files and documents carry no capture date the app can rely on, and plenty of pictures have had theirs stripped by an editor or a messaging app. For those, AssetScout falls back to the file system and takes the older of the two dates it keeps.

That date describes the file, not its contents. A picture saved from a chat in 2019 and copied to a new Mac in 2024 will sit in 2024. Its position in the grid is a guess, and it can be wrong by years.

Because it can be wrong, it can be marked. Switch Mark items without a capture date on in Settings and every item placed this way carries a mark, so you can see at a glance which parts of the order to trust. It is off to begin with, because in a folder of downloaded files nearly everything would carry it.

One date, three things

Whichever mode is chosen, the same date drives all three of these at once:

• which month heading the item falls under,
• where it sits inside that month,
• and the date written under its thumbnail.

They can never disagree, which means the label under a thumbnail is always the reason it is where it is.

Rotating changes a date

Turning a picture writes the file, and the file system then stamps it with today's modification date. While the grid is grouped by Last Modified that would silently move the item to another month, so AssetScout asks what should happen — once per scan, before the first rotation — and uses your answer for the rest of that scan. See Rotating and flipping.