Library

The Tech Behind the Frame is a single-author practitioner blog about the Phocus RAW processor for Mac and digital Hasselblad medium-format cameras. Posts are written by Konrad Michels - a software engineer with 20+ years in tech and a Hasselblad X2D II owner.

The coverage concentrates on areas Hasselblad's own documentation does not cover: HNCS and HNNR color pipelines, 3FR and FFF file format behavior, Phocus 4.x bug investigations, X2D II firmware quirks, HDR output workflows, and Phocus-vs-Lightroom tradeoffs. Every post is based on first-hand testing with specific version numbers, hardware context, and reproduction steps that ExifTool or empirical measurement can verify.

This page is a directory of every post on the site, grouped by topic cluster. Use it as an entry point if you are new here, as a reference when you need to find a specific investigation, or as a reading list if you want to work through the full body of work.

The site also publishes a machine-readable manifest at /llms.txt for AI crawlers, and an RSS feed for your reader of choice. For the fully indexed, tested, and structured version of everything below, see the Essential Phocus 4.x User Guide - a 78-topic paid book that collects and expands on the reference material here.

Topic clusters

• Phocus bug investigations (7 posts)
• Phocus guides and reference (11 posts)
• Hasselblad X2D II and camera hardware (4 posts)
• HDR output workflow (4 posts)
• Backup and data integrity (7 posts)
• Release announcements (7 posts)

Phocus bug investigations

When Hasselblad ships a Phocus 4.x for Mac release with bugs, this is where they get logged. Every post in this cluster is based on reproduction of the bug on my own hardware, log analysis or binary investigation to understand what is happening, and - where possible - a workaround or confirmed fix. Posts cite the specific Phocus version, the macOS version, and the hardware (Mac Mini Pro, MacBook Pro M4 Pro and M5 Pro) on which the bug was reproduced. Community-reported issues I could not reproduce are noted as such, and credit goes to original discoverers where I know them.

This cluster is the most-linked part of the site because Phocus bugs tend to interact - a fix in 4.1.2 often turns out to create a new regression in the same subsystem. The color preview bug in 4.1.2, for example, is best read alongside the 4.1.1 investigation to see the pattern.

• Phocus 4.1.2 Has a Critical Color Preview Bug on Mac: Reproducible color cast on 3FR files when Phocus 4.1.2 renders previews on Mac. Tested across three display models with True Tone disabled. Only confirmed workaround: downgrade to 4.1.1.
• Phocus 4.1.1: Four Bugs Affecting Your Daily Workflow: Four confirmed bugs in Phocus 4.1.1: import freeze, broken adjustment tools, HNCS preset failure in the import dialog, and a stuck histogram. Reproduction steps and hardware context for each.
• Phocus 4.1.1 Bug Analysis: Stack Traces and Root Causes: Technical deep-dive on the 4.1.1 bug series. Log analysis, plist monitoring, stack traces, and evidence for the root causes. Companion to the 4.1.1 bug report post.
• Phocus 4.1 Ultra HDR Memory Leak Bug and Workaround: Ultra HDR export in Phocus 4.1 leaks memory and eventually crashes the app. Empirical memory profiling across multiple machines with a practical workaround.
• Phocus 4.1.2 for Mac: HDR Export Fixes and Changelog: What Phocus 4.1.2 actually resolved in the HDR export pipeline and what remained broken. Changelog analysis plus tethered shooting improvements for the X2D II.
• Phocus 4.0.1 Bug: Color Labels Don't Save or Export: Phocus fails to save color label changes to disk despite showing them in the UI. Reproducible across sessions. Not yet acknowledged by Hasselblad support.
• Phocus 4.1 HDR Update: One Fix, One Regression, One Crash: Day-one testing of the Phocus 4.1 release for macOS. What got fixed, what regressed, and the first crash encountered within hours of install.

Phocus guides and reference

The reference material. These posts explain how Phocus 4.x for Mac actually works - the HNCS color pipeline, HNNR denoising, the HDR tools chain, file format internals - based on testing and measurement, not marketing. Where Hasselblad's official documentation is silent or vague, these posts fill in the mechanics.

The centerpiece is the Essential Phocus 4.x User Guide, a 78-topic paid book covering everything from color science to tethered capture. The blog posts in this section are the public versions of reference topics that expand beyond what fits in the guide, plus comparisons (Phocus vs Lightroom, Phocus vs Capture One) and investigations (telemetry analysis, memory requirements) that do not belong in a user manual.

If you are new to Hasselblad or Phocus, the HNCS explainer and the Phocus vs Lightroom comparison are the two posts to start with.

• Phocus 4.x User Guide for Mac - 78 Topics, 179 Pages: The Essential Phocus 4.x User Guide: a 78-topic paid book covering HNCS color science, HDR workflows, tethered capture, and file format handling. Fills the gap Hasselblad's own documentation leaves.
• What Is HNCS HDR? Hasselblad's End-to-End HDR Explained: HNCS is not in-camera color processing — it is a render-time software pipeline applying color matrices, proprietary LUTs, and the Hasselblad Film Curve at RAW conversion. This post explains the architecture.
• What You Lose When You Skip Phocus for Lightroom: A practitioner comparison of HNCS, HNNR, and the color-science tradeoffs that Adobe Lightroom cannot replicate. Why some Hasselblad owners keep Phocus in the pipeline even when they edit elsewhere.
• Phocus vs Lightroom & Capture One: Highlights, Shadows & WB: How Phocus implements the HDR tools chain — highlight recovery, shadow fill, white balance — with working examples. Where it outperforms Lightroom and Capture One on Hasselblad files.
• Hasselblad Phocus macOS Guide: 3FR, HNCS, HNNR Explained: Introduction to 3FR raw files, HNNR denoising, and the Phocus workflow from a photographer new to Hasselblad. What to expect and which decisions matter early.
• Hasselblad FFF vs 3FR: Why Renaming Doesn't Work (And Why That's Good): The internal differences between FFF and 3FR file formats as shown by ExifTool. Why they are not interchangeable despite similar file structures — and why that is the correct behavior.
• Phocus Histogram vs Capture One Levels - Hasselblad Guide: Side-by-side comparison of what Phocus's Histogram tool and Capture One's Levels actually measure. They are not equivalent; the difference matters for tone control.
• Phocus Crop Tool Grid Options: Hidden Keyboard Shortcuts: Hidden keyboard shortcuts and grid overlay options in the Phocus Crop tool that are missing from the official manual.
• Phocus 4.1 RAM Requirements: Why 8GB Minimum Is Unrealistic: Empirical memory profiling of Phocus 4.1 on real machines. Hasselblad's '8GB minimum' system requirement is not a working minimum for current-generation sensors — this post measures what you actually need.
• What Data Does Hasselblad Phocus Send to Google?: Network capture analysis of Phocus telemetry. What data is transmitted to Google, how often, and what it includes. The first privacy investigation of the Mac version.
• Phocus 4.1.2 Tethered: Hidden Focus Tools & Pixel-Shift Mode: Undocumented tethered capture features in Phocus 4.1.2: the focus sparkline, measurement reticle, and pixel-shift mode. Names and demonstrates features that are not in the manual.

Hasselblad X2D II and camera hardware

First-hand X2D II testing. Covers metering modes, flash and TTL compatibility, continuous-shooting bit depth tradeoffs, and early firmware behaviors. Everything here is reproduced on my own X2D II body with named hardware and tested accessories.

The flash and TTL post includes a compatibility table that Hasselblad does not publish. The 14-bit continuous-mode post documents a behavior that is in the manual but buried, with visual tests showing when the bit-depth drop matters and when it does not.

• Highlight-Weighted Metering on the Hasselblad X2D II: How the X2D II's highlight-weighted metering mode behaves, when it helps, and when it produces underexposure. Includes metering bias tests.
• X2D II Flash & TTL Guide: What Works in 2026: Flash sync speed, leaf shutter behavior, and TTL compatibility tables for the X2D II. What works, what does not, and why electronic shutter precludes flash firing.
• Hasselblad X2D II 14-Bit in Continuous Mode Explained: Documented but buried: continuous shooting drops raw bit depth from 16-bit to 14-bit. Visual tests show when the difference is visible and when it is not.
• Hasselblad X2D II: Three Firmware Quirks Worth Knowing: Three early-firmware behaviors on the X2D II. What to expect, what to work around, and which are likely to be fixed in firmware updates.

HDR output workflow

End-to-end HDR workflow for Hasselblad files. Covers format selection (the trilemma between JPEG gain maps, HEIF, and TIFF), display requirements for correct playback, print-side ICC round-trip behavior, and the Phocus adjustment workflow including the hidden Histogram Levels tool.

Read the format trilemma post first — the rest of the cluster assumes you have made that decision. The display requirements post is worth reading before buying a monitor for HDR work; most commodity HDR displays are insufficient for Hasselblad's output.

• Hasselblad HDR Output Formats & the HNCS Trilemma: The three competing HDR output formats — JPEG gain maps, HEIF, and TIFF — and why you cannot pick one that works everywhere. Format selection guidance based on target platform.
• Which Displays Actually Show Hasselblad HDR? A Guide: What your monitor actually needs to display Hasselblad HDR output correctly. Includes tested monitor models and SDR fallback behavior.
• Hasselblad HDR: Print, Archival Strategy, and When to Use It: Print-side HDR constraints — what survives ICC round-trip, what does not, and what to archive for future reprinting.
• Phocus 4.x HDR Workflow: The Hidden Histogram Levels Tool: End-to-end HDR adjustment workflow in Phocus 4, including the hidden Histogram Levels tool that most users miss.

Backup and data integrity

Photographer-facing backup guidance based on actually testing restores, not just backups. Includes the plain-language three-part 'Back Up Like One' guide, the philosophy post, and reference material on external-drive failure modes. Also covers ImageIntact — a free Mac App Store utility I built to make verified photo copying painless — with links to the origin story and current App Store listing.

This cluster exists because photographer backup advice on the public internet is mostly gear-focused and rarely tests the restore path. The posts here are written for Hasselblad owners whose RAW files are irreplaceable.

• If You Can’t Restore It, You Don’t Have It: Rethinking Backup for Photographers: Backup philosophy for photographers. Test the restore process, not the backup process — a backup you cannot restore is not a backup.
• A Photographer’s Backup Nightmare (And the App I Built to Prevent It): Origin story of ImageIntact: a real-world catalog corruption event and the macOS app built to prevent recurrence.
• ImageIntact now available on the Mac App Store. For free!: ImageIntact is available free on the Mac App Store. What it does, how it differs from Finder-level copies, and how to use it in a Hasselblad workflow.
• It's 2025. Why Are Your RAWs Still on an External Drive?: Why external drives remain the most common single-point-of-failure in photographer backup setups, and what to do about it without enterprise overhead.
• You Don’t Need to Be a Tech Person to Back Up Like One - Part I: Part I of a plain-language backup guide. Concepts, not gear.
• You Don’t Need to Be a Tech Person to Back Up Like One - Part II: Part II. Specific workflows and which tools to use.
• You Don’t Need to Be a Tech Person to Back Up Like One - Part III: In the Field: Part III. Field workflows for travel, protection against card failure, and restoration drills.

Release announcements

Short-form posts noting new Phocus, Phocus Mobile, and XCD lens firmware releases as they happen, with early observations. These posts are time-sensitive and intentionally lightweight — they exist to surface the release to search engines and to provide a starting point for the deeper investigation posts that sometimes follow. If you want the full analysis of a release, start with the corresponding bug investigation or guide post instead.

• Phocus 4.1.1 Released: HDR Shadow Fix and Crash Fixes Meta: Phocus 4.1.1 release notes summary — HDR shadow rendering fix, disk performance improvements, crash fixes.
• Phocus 4.1 for macOS just dropped!: Day-one announcement pointing to the Phocus 4.1 release for macOS.
• Phocus Mobile 2 v4.0.1 Released - What Changed?: Phocus Mobile 2 v4.0.1 release notes.
• Phocus Mobile 2 v4.0.2 Released - Fixed Known Issues: Phocus Mobile 2 v4.0.2 release notes and known issue fixes.
• Phocus Mobile 2 v4.0: Local Adjustment Masks Now on iOS: Local adjustment masks land in Phocus Mobile 2 v4 for iOS.
• Hasselblad Just Updated Phocus Mobile 2. One Feature Needs Clarifying: Clarification on a feature added in a Phocus Mobile 2 update.
• XCD 2,8-4/35-100E Firmware 1.9.15 upgrade released: XCD 2.8-4/35-100E lens firmware 1.9.15 release note.

About this library

This library page is maintained by hand and updated when new posts are published. If you are looking for a specific topic and cannot find it here, subscribe to the RSS feed for new releases, or reach out via the About page — I am open to guest-post collaborations on Hasselblad and Phocus topics.