Feature Guide
Crop & Coverage Tool
In DevVisualise how a lens's image circle covers different sensor sizes with real-time crop line overlays on test imagery.
In Development
The Crop & Coverage tool is currently in development. It is partly inactive and may have limited functionality across some areas of the site. We're actively working on expanding its coverage and reliability.
What Is Crop & Coverage?
The Crop & Coverage tool lets you see beyond the standard framing of a lens, showing how the optical image circle extends past common sensor boundaries. It overlays crop lines for different sensor sizes — Super 16, Super 35, Full Frame, VistaVision, and more — directly on the test imagery, so you can instantly evaluate edge performance, vignetting fall-off, and coverage without needing a separate calculator.
Crop & Coverage overview video — coming soon
Extended Coverage
Beyond standard crop lines, there's a very special capability we're building called Extended Coverage. This is a step above regular crop line overlays — it's designed to show you larger-than-rated coverage on particular lenses, allowing you to see how Super 35 lenses work on Full Frame, and how Full Frame lenses work on medium format cameras. This is something no test has ever explored before.
Explore lens performance beyond rated coverage
Extended Coverage is a step beyond standard crop lines. It shows you lens performance at larger-than-rated sensor sizes — how a Super 35 lens actually renders on Full Frame, or how a Full Frame lens handles medium format. This is territory no lens test has explored before.
You'll be able to preview the lens exactly as you'd expect it to perform, but then push beyond that rated coverage to see the full character of the optic at its limits — the vignetting fall-off, the edge distortion, the swirl, and most importantly, whether the image is still usable.
The real discovery
There are lenses out there that cover Full Frame close enough, despite being designed for Super 35, that they produce truly unique and beautiful looks when pushed beyond their rated format. Extended Coverage is built to find and highlight exactly those lenses — the ones nobody knew about.
Real-World Examples
Clears Full Frame coverage with stunning results — a Super 35 lens producing beautiful, usable imagery well beyond its rated format.
Clears coverage enough that you get crazy field curvature — a wild, character-rich look that nobody expected from a Super 35 lens on Full Frame.
How to Use It
Look for the Coverage button in the toolbar on lens detail test views. Clicking it opens a dropdown where you can toggle the overall coverage overlay and individually enable or disable specific crop lines. Each crop line has its own colour for easy identification. The overlay appears directly on the test image, so you can see exactly where each sensor boundary falls relative to the lens's actual performance.
Crop Lines
Crop Lines
Crop lines show the exact boundaries of common sensor sizes overlaid on the test image. You can toggle each one independently — Super 16, Super 35, Full Frame, VistaVision, and more. Each line is colour-coded so you can distinguish between formats at a glance. You can also enable all crop lines simultaneously to compare how many formats a lens covers in a single view.
Screenshot showing multiple crop lines overlaid simultaneously
Evaluating Edge Performance
The primary value of the coverage tool is seeing how a lens behaves at the edges and corners for your specific sensor size. A lens designed for Super 35 may show strong vignetting when used on a Full Frame sensor — the crop lines make this immediately visible. This is especially important when repurposing vintage lenses on modern large-format cameras.
Screenshot showing vignetting visible at Full Frame crop line boundaries
Tier Requirements
Extended Coverage is available to Indie and Hollywood tier members. If you're on the free tier, the coverage button will be visible but disabled — upgrading unlocks full access to the overlay and all crop lines.
Current Limitations
As this feature is still in development, there are known limitations — it may not work perfectly in fullscreen mode, and compatibility on the Compare and Discover pages is still being refined. We recommend using the PHFX tools (linked in the Coverage dropdown and under Tools in the navigation bar) for precise lens coverage verification while we continue to build this out.
Screenshot showing crop lines overlaid on a lens test
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