Kaleidoscope 6.6 is out today, introducing AI-powered image alignment built on Apple’s Vision framework. Whether you’re comparing screenshots or photographs, Kaleidoscope will now automatically align images based on their content.
In addition, this release brings refinements to the recently introduced Pixel Comparison, which we’ll cover below.
Automatic Alignment
When designing this feature, we focused on two common real-world use cases:
Screenshots
Comparing screenshots — whether taken manually or generated by automated UI tests — is a common workflow in Kaleidoscope.
The challenge? Not all screenshots match perfectly in size or layout.
Kaleidoscope 6.4 introduced improved edge and corner alignment options. Kaleidoscope 6.6 takes this much further: images are now automatically aligned based on their content when opened.
In most cases, alignment works instantly and requires no interaction. If needed, it can still be precisely adjusted.
Photos
The second major use case is comparing photographs, especially RAW images straight from the camera.
Kaleidoscope’s four distinct view modes and Pixel Comparison already make it powerful for evaluating both content and technical aspects like exposure, color range, and sharpness. When combined with the File Shelf, it even works well for photo culling.
But aligning photographs is a different problem. While images from digital cameras typically share the same dimensions, their content rarely aligns perfectly due to slight camera movement — even when mounted on a tripod.
Kaleidoscope 6.6 aligns photos automatically based on their content, even when perspective, rotation, or framing differ between shots.
Manual Alignment and Offset
Automatic alignment covers most situations, but when you need control, the updated alignment interface provides it.
You can access alignment via the toolbar button or menu command View > Image Alignment…
The primary choice is between Position and Perspective alignment:
- Position applies a two-dimensional shift and is often ideal for screenshots.
- Perspective accounts for three-dimensional differences caused by camera movement and is typically better suited for photographs.
The good news: Kaleidoscope usually selects the appropriate mode automatically.
If needed, you can override automatic alignment or apply a manual offset. When working with images of different sizes, anchor edges and corners remain available in manual mode.
While the alignment view is open, the rest of the app remains fully functional. You can:
- Switch view modes using keyboard shortcuts (⌘1 to ⌘4)
- Toggle between image A and B in One-Up or Difference view (⌘◀︎ and ⌘▶︎)
- Press S in One-Up view to start or stop automatic switching
- Zoom and pan using your trackpad
The alignment view also supports these keyboard shortcuts:
- O for Position
- E for Perspective
- A for Automatic (in Position mode)
- M for Manual (in Position mode)
Pixel Comparison Enhancements
Based on your feedback, Kaleidoscope 6.6 includes several improvements to the Pixel Comparison.
Additional Customization
Automatically Collapse Info Views
When vertical space is limited, Kaleidoscope automatically collapses the two info panels showing pixel details for images A and B. You can now disable this behavior if you prefer them to remain visible or manually collapse them.
Always Prefer Float Values
Just like there are two ways to pronounce GIF, there are two ways to express color channel values:
- As floating-point values (typically 0–1.0)
- As integer values (typically 0–255)
Previously, Kaleidoscope defaulted to integers if all values fit within that range. You can now choose to always prefer float values. Thanks, Max!
Better Extended Range Support
Representing color accurately in software is tricky business. Modern cameras and displays can capture and render beyond the traditional 0–1 range. High dynamic range formats such as EXR can span many magnitudes. Kaleidoscope 6.6 improves handling of extended color ranges by:
- Clearly indicating default maximum values
- Using logarithmic (including double logarithmic) scaling for large ranges
- Improving range handling for HSB, HSV, and Lab formats
These changes make both slight and extreme color differences easier to interpret and compare.
Conclusion
Tools work best when they stay out of the way. Kaleidoscope 6.6 removes one of the last bits of friction from image comparison: getting things to line up in the first place. With alignment handled automatically, you can focus on what actually changed — and understand those differences with the precision Kaleidoscope is built for.
