Contents
Image duplicates & series
The image comparison finds not only exactly identical images but also similar ones: the same shot at a different resolution, lightly edited variants or entire photo series. It also rates the image quality and automatically proposes the best image of each group to keep — ideal for pulling the one good photo out of a series and sorting out the duplicates.
10.1 Opening
The header bar holds the drop-down image module switch (icon with a picture frame and “▾”, tooltip “Open image modules — image comparison or metadata (ShotScope)”). It offers two entries: 🖼 Image comparison and 🏷 ShotScope (chapter 12). The two views are mutually exclusive; the switch is only usable with an active job.
10.2 Two modes: pixel comparison or photo series
On the left of the control bar sits the mode drop-down. The button always names the mode currently active; a click opens the list containing both options, with a tick on the active one:
| Mode | Finds… |
|---|---|
| 🖼 Pixel comparison | identical and perceptually similar images — across the whole folder, regardless of when they were taken |
| 🎞 Photo series | shots that belong together: images are bundled into series by EXIF capture time and camera, then refined within by similarity |
Switching regroups immediately, without another scan. The first time you switch to 🎞 Photo series, the EXIF capture data is read in — this takes a moment and is shown.
The Threshold: slider (the “−”/“+” buttons change it in 5 % steps) determines how strictly “similar” is meant. At the very top, 100 %, only byte-identical images count — the comparison then works like a pure image duplicate finder. The lower you set the threshold, the more variants end up in one group. In 🎞 Photo series mode the Time gap slider (in minutes) is added: it defines the pause between shots at which a new series begins.
10.3 Result, quality and selection
The findings appear as group cards whose header names the kind: “≡ Identical”, “≈ Similar” (with a percentage) or “🎞 Series”. Every image is a tile with a preview, a Keep tick, the file name, information (size, resolution) and a quality rating in stars (★ to ★★★★★). The stars combine seven measurements — among them sharpness, resolution, contrast, exposure, colour, freedom from noise and level of detail; a tile’s tooltip shows the individual values. A double-click opens the image in the original view. If you want to see these seven values for two images side by side, use the quality bar in the image comparison viewer (section 10.4).
In every group the image with the best quality is automatically pre-selected to be kept (green frame), the rest are marked for removal (red frame). Two buttons per group change that:
| Button | Effect |
|---|---|
| ✓ Keep best | keeps only the best image (default) |
| Keep all | keeps all images of the group |
| ⇆ Compare | opens the image comparison viewer for this group (section 10.4) |
Individual images can additionally be ticked or unticked by hand.
Reviewing all remaining images: “Show unassigned”
A group needs at least two images. A shot with no similar counterpart therefore does not appear anywhere — correct for duplicate hunting, but useless when reviewing an entire shoot: exactly the largest part of the yield is missing there, and you can neither view nor compare nor select those images.
The Show unassigned box in the toolbar closes this gap. When switched on, further cards headed “◇ Unassigned #1, #2 …” appear below the findings, containing all remaining images. They behave like any other group: tiles with stars, double-click for the original view, ⇆ Compare opens the image comparison viewer.
| Property | Why it is so |
|---|---|
| All images start red (deselected) | This reverses the direction of work: you pick what should stay instead of sorting out what should go — the usual approach when reviewing a shoot. Whatever stays red, however, moves to the cache when you apply the selection; see the warning below. |
| At most 10 images per card | A card with hundreds of tiles cannot be taken in at a glance. |
| Sorted by capture time, split at time gaps and camera changes | This keeps together what was created together — otherwise they would be arbitrary groups of ten, and a comparison inside would compare random things. The time gap takes priority: better a card with six images of one situation than ten spread across two. |
| Cards start collapsed | A shoot easily produces hundreds of them; the findings should stay at the top. |
| Do not count as findings | The header (“N groups · M images detected”) still refers only to genuine similarity findings. |
10.4 Comparing two images directly (image comparison viewer)
With similar shots a detail often decides: is the left image really sharper? Did someone blink? For that purpose every group card carries the ⇆ Compare button next to the keep buttons. It opens the image comparison viewer for exactly that group — there you place two images side by side, examine them in four display modes and mark the good ones green. The viewer changes only the keep markings; nothing is deleted or moved.
Layout
The window has two comparison containers: Comparison 1 (left) and Comparison 2 (right). At the bottom there is a thumbnail bar with all images of the group. This is how you assign images:
| Action on the thumbnail | Effect |
|---|---|
| Button 1 or 2 | load the image specifically into Comparison 1 or Comparison 2 |
| Left-click on the tile | load the image into the active container |
| Right-click on the tile | load the image into the other container (the active one stays as it is) |
| Tick at the top right of the tile | keep the image (green) or discard it (red) |
The active container is the one you are currently working with — recognisable by the coloured line beneath its header. You can switch it at any time with a click on the header of the container you want; in Side by side mode a click into the respective image is enough as well. That way you can carry on working on the right, for example, without the thumbnail bar overwriting the left image every time.
The orange marker ① or ② on the tile shows at all times which image is in which container. The tile’s frame remains the familiar traffic light: green = kept, red = will be sorted out — the same marking as in the group card behind it.
Each container’s header carries the keep tick right next to the file name, beside it the decision in words (“✓ will be kept” / “✕ will be discarded”), and with unequal quality the marker “▲ better” on the higher-rated image — plus the Apply image button on the right. Below that come size, resolution, date and star rating.
The quality bar beneath the images
Beneath the images there is a breakdown of the star rating for each container. On the left stands the container label with the overall score (e.g. “★★★★ 67 %”) in the colour of the stars; below it appear the seven measurements that make up this score — each with a percentage and a small bar. In Side by side mode each breakdown therefore sits directly beneath its image.
| Measurement | What it judges | Share of the score |
|---|---|---|
| Sharpness | edge definition — the most important indication of whether a shot is spot on or slightly blurred | 25 % |
| Resolution | image size in pixels | 20 % |
| Contrast | tonal range between the brightest and darkest areas | 15 % |
| Exposure | distribution of brightness values; blown highlights and crushed shadows cost points | 10 % |
| Colour | saturation and colour variety | 10 % |
| Noise | freedom from noise — the higher the value, the cleaner the image | 10 % |
| Detail | level of detail in relation to the file size; low values indicate heavy JPEG compression | 10 % |
If the two containers hold different images, the better of the two is highlighted in green for each measurement. The “▲ better” marker in the header tells you which image is rated better overall — the quality bar tells you why. If a container is empty or the same image is in both, the highlighting is omitted.
The bar stays visible in all four display modes — the values belong to the two containers, not to the image arrangement. In the modes with a shared image area (Overlay, Slider, Difference) you recognise the assignment by the container label in the same colour as in the header above. ⇄ Swap swaps the breakdowns along with the images.
The four display modes
| Mode | Shows… | Own slider |
|---|---|---|
| Side by side | both images separately next to each other | — |
| Overlay | comparison 2 lies on top of comparison 1 — ideal for spotting shifts and blur | Opacity 0–100 % |
| Slider | a vertical dividing line: comparison 1 on the left, comparison 2 on the right | Position 0–100 % or drag the handle directly in the image |
| Difference | only the deviation between the two images: black = identical, bright areas = difference | Amplification 1–10× |
In Difference mode the footer additionally gives figures: “Ø deviation … % · maximum … %”. A value close to zero means the two images are practically the same. In the other modes the metadata comparison appears there: “Comparison 2 versus 1 — resolution … · size … · quality …”.
Tools
| Tool | Function |
|---|---|
| ⇄ Sync | zooming and panning act on both images at once (default: on). Switched off, the zoom applies only to the active container — marked by an orange line beneath its header. |
| Blink | alternates continuously between the two images. Even the smallest differences in sharpness or composition become visible as movement. |
| Grid | displays a rule-of-thirds grid — helps when comparing composition and horizon alignment. |
| ⇄ Swap | swaps the contents of comparison 1 and 2. |
| Zoom, 1:1, Fit | slider up to 800 %; the mouse wheel zooms at the cursor position, dragging with the left mouse button pans, a double-click fits the image. |
How to work through a group
- Click ⇆ Compare in the group card.
- Assign two images — using 1 and 2 in the thumbnail bar. After that a left-click on a tile is enough to reload the active container.
- Choose a display mode and examine (with nearly identical images, Difference or Blink leads to a decision fastest).
- For every image that should stay, press Apply image — or set the tick next to the file name.
- Assign the next pair and carry on. The arrow keys ← / → page through the group in the active container.
- Return to the group view with ✓ Apply & close.
10.5 Removing — with a safety net
You trigger the actual sorting-out with ✓ Apply selection — the button sits in the module’s bar, to the right of 🔍 Scan. The deselected images are then not deleted immediately but moved to a temporary recycle-bin cache; afterwards the image result view opens (“✓ Result — N images remaining”). There you find:
| Button | Function |
|---|---|
| 🗑 Remove | move further deselected images to the cache (“Only deleted for good when you finish”) |
| ↩ Undo | bring all images back from the cache and return to the duplicate view |
| ✓ Finish | confirm the clean-up — the cached images are now deleted for good |
10.6 Merging series
With 📁 Copy selection you collect the kept (green) images of every group in a subfolder of their own beneath a target folder you choose — the originals are preserved (they are copied, not moved). SynQaiPro proposes the name of the series subfolder; you can adjust it per card. Should there be name collisions, the renaming kit (chapter 7) opens automatically so that all images get unique names.
