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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, an engineer who shoots: 30 years in software, with the X2D II as his primary camera.

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 85-topic paid book that collects and expands on the reference material here.

If you need personalized help with your Phocus workflow, HDR pipeline, or want a bug report reviewed before submitting to Hasselblad, see the Work With Me page.

Topic clusters

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 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 85-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.

  • What Is Hasselblad Phocus? A Free RAW Editor for Mac: What Phocus actually is for anyone deciding whether to bother with it: a free, no-account RAW processor that's the only application rendering Hasselblad's proprietary HNCS color science. Covers what the app does day to day, a direct comparison table against Lightroom Classic and Capture One, the real RAM floor for 100-megapixel files (Hasselblad's 8GB figure isn't it), and when skipping Phocus for another editor costs you the color rendering that makes a Hasselblad file look like one.
  • The Phocus 4.x User Guide for Mac (paid book): The 85-topic user guide for Phocus 4.x on Mac. Available as a $49 digital download and as a paperback through Lulu. Covers what Hasselblad's official 3.8 documentation does not.
  • Hasselblad & Phocus Glossary: Every Term Explained: Reference glossary for HNCS, HNNR, 3FR, FFF, X-System acronyms, and the Phocus-specific vocabulary that appears across the blog. Definitions aim for accuracy without padding.
  • Phocus for Mac: Version History and Changelog: Running record of every Phocus 4.x release for Mac, with notes on what each version actually changed, including regressions and issues that Hasselblad's official release notes do not mention. Updated as new versions ship.
  • Why Your Phocus Workspace Keeps Resetting: Phocus workspace customization only persists in custom layouts. Built-in layouts are read-only. Here's how to fix it.
  • Where Did My Star Ratings Go? Phocus Thumbnail Options: Found a non-obvious dropdown in Phocus 4.1.2 that controls thumbnail filtering, sorting, and display. Here's what each option does.
  • How to Create a New Collection in Phocus 4.x: Phocus has exactly one collection (Quick Collection) and no UI to create others; covers how to add and remove images via keyboard shortcut, drag-and-drop, or right-click.
  • Phocus 4.x User Guide for Mac - 85 Topics, 251 Pages: The Essential Phocus 4.x User Guide: a 85-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.
  • How HNCS Actually Works: Hasselblad's Color Science Explained: The render-time HNCS pipeline explained mechanism by mechanism: illuminant matrix selection, chroma correction LUTs, and the Hasselblad Film Curve. Includes measured .phos sidecar data showing the five factory presets change sharpening and tone curve, not the underlying color science.
  • 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.
  • What Phocus Writes to the .phos When You Switch HNCS Presets: Empirical inspection of the .phos sidecar reveals what Phocus actually records per HNCS preset (Standard, Nature, Portrait, Product, Square Crop). Per-preset slider deltas, the Name and ReferenceSettingName fields the Adjustments dropdown never surfaces, and a public correction to the earlier ‘preset isn’t recorded anywhere’ claim.
  • How Phocus Stores Color Labels and Approval Ratings: Where Phocus actually stores color labels: the .phos sidecar's Approval key for 3FR, the MakerNote tag for FFF, and how to read either yourself.
  • How HNNR Works in Phocus: Architecture from Binary Analysis: What the Phocus app bundle reveals about HNNR - 8 CoreML models encrypted for the Apple Neural Engine, a hybrid CPU+GPU+ANE pipeline, and why chip generation (not Pro/Max tier) drives denoise speed.
  • Color Calibration and the Reproduction Tool in Phocus: How to build a custom Color Calibration from a reference target and use the hidden Reproduction tool (Working Space, Input Profile, Response) for copy stand, studio, and archival color fidelity.
  • Capture One's Hasselblad Support: What You Get and What Stays in Phocus: Capture One 16.8.3 opens 3FR files natively from the X2D II 100C, X2D 100C, and CFV 100C, the product of a formal partnership announced July 2, 2026. A close read of the launch materials: both companies describe the rendering as Capture One's own color (HNCS is named nowhere), there is no HDR output, FFF files stay Phocus-only, and Hasselblad RAWs carry no readable focus-distance metadata, which means every third-party converter has been applying distance-generic lens corrections. Includes Hasselblad's on-record statement that the partnership "isn't a replacement for Phocus."
  • A Complete Hasselblad RAW Workflow: Cull, Phocus, 16-Bit TIFF, Lightroom: The end-to-end pipeline in one place: cull in Palomino, apply only the RAW-dependent steps in Phocus 4.2 (HNNR, white balance, highlight recovery, shadow fill, lens corrections), export with the built-in TIFF-16 preset, and finish in Lightroom Classic. States the boundary rule that decides which app owns which adjustment, and why global exposure never gets baked into the TIFF.
  • Culling a 1,500-Frame Hasselblad Shoot in Fifteen Minutes: How a 1,500-frame card gets sorted in 10 to 15 minutes in Palomino, handing clean keepers and their star ratings to Phocus instead of culling inside it.
  • Phocus, Capture One, or Lightroom? I Measured Instead of Guessing: The same X2D II 3FR rendered at defaults in Phocus 4.2, Capture One 16.8.3, and Lightroom Classic 15.4.1, then measured rather than eyeballed. Tone, color, and lens handling differ more than you would guess.
  • Hasselblad RGB Is Wider Than Adobe RGB: The measured primaries of both Hasselblad working spaces, decoded from the ICC profiles Phocus installs. Adobe RGB fits entirely inside Hasselblad RGB; Display P3 and ProPhoto cross it rather than nest. Includes an interactive chromaticity diagram and what an Adobe RGB export costs on a real frame.
  • Phocus 4.x Release Notes vs What Actually Shipped: The read-me PDFs are the only official record of Phocus 4.x. This page keeps score on how complete that record actually is, release by release.
  • Phocus for Mac - Import flow to ensure HNCS is Applied: The exact import settings that make sure HNCS color rendering is applied to your files, with a video walkthrough.
  • I Asked Hasselblad Which Render Is the Real HNCS. Wrong Question, as it turns out.: Hasselblad engineering's written definition of HNCS, obtained over twelve days and two support cases: an always-on stage inside every Phocus render, in both the Mac and Mobile apps. Why that dismantles the question of which render is the real one, the retraction it forced of an earlier import claim, and the lens-correction gap that stays open.
  • The Phocus Grayscale Panel Is a Real Channel Mixer: The Grayscale sliders look like a global brightness control and black the frame out at -100. Measured on a ColorChecker frame, they are a per-channel luminance mixer with absolute RGB weights, unlike Lightroom's hue-based Black & White Mix, with defaults that match the Rec. 709 luma weights. Also covers the filter presets and why the Histogram panel ignores the conversion until Output values is ticked.

Hasselblad X2D II and camera hardware

First-hand X2D II testing plus a running firmware changelog. Covers metering modes, flash and TTL compatibility, continuous-shooting bit depth tradeoffs, and everything added or changed in firmware since launch. 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.

  • Hasselblad X2D II RAWs Record Focus Distance. Now Your Editor Reads It: Every X2D II 3FR since firmware 1.2.7.11 carries data from which real focus distance can be recovered, in private fields no editor could read. Since firmware 1.3.16.1 the camera also writes the standard EXIF field, and Capture One and Lightroom Classic both read it and use it for distance-dependent lens corrections. Includes the controlled test ladder and the render tests.
  • Add Focus Distance to Older X2D II RAW Files: A free open-source tool that computes focus distance from data the camera has recorded since firmware 1.2.7.11 and writes it into the standard EXIF field, so Lightroom and Capture One apply the right lens correction to files shot before firmware 1.3.16.1. Works on copies; originals are never modified.
  • 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 100C: RAW Bit Depth, Buffer, and Continuous Shooting Specs: What Hasselblad's official datasheet, FAQ, and product page actually say about the X2D 100C's RAW bit depth (16-bit baseline), continuous shooting speed (3.3 fps, tied to 14-bit), and buffer depth (not published anywhere). Unlike the X2D II, the 100C doesn't force 14-bit the moment you switch to Continuous drive mode - Hasselblad's own FAQ and product page describe 16-bit as available there too, just not confirmed at the peak rate.
  • 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.
  • Hasselblad X2D II Firmware Updates Since Launch: The running reference for every X2D II firmware release, the new features and behaviour changes that are not in the v1.0 manual, and the complete version-by-version changelog. Updated as Hasselblad ships firmware.
  • Hasselblad Firmware Tracker: a live, daily-checked reference for the current firmware version of every X System body, XCD lens, and adapter.
  • Triggering a Hasselblad X2D II With a MIOPS Smart Trigger: A passive 2.5-to-3.5mm adapter will not fire the X2D II, because the shutter control port triggers on the ring while generic triggers (MIOPS, Pluto, intervalometers) put the signal on the tip. Includes the Release Cord X pinout measured on a multimeter, the two-wire MIOPS cable that works, the build gotchas, and a lightning-safety note.
  • Hasselblad X2D II vs X2D 100C: Is the Upgrade Worth It?: The X2D II 100C launched at $7,399, undercutting the now discontinued X2D 100C by $800. What actually changed between the two bodies, and who the upgrade is worth it for.
  • The Hasselblad X2D II Autofocus System: How the 425-zone PDAF array, LiDAR assist, and AF-C subject detection work on the first Hasselblad that can follow a subject across the frame, plus the constraints that do not show up on the spec sheet.
  • Earth Rotation Compensation on the X2D II: The 4-Hour Location Window: The X2D II's Earth rotation compensation depends on location data that only reaches the camera when you connect Phocus Mobile 2, and that data goes stale after 4 hours.
  • The Hasselblad X2D II Is ISO Invariant from ISO 200: My Measurements: On my X2D II, shadow noise at ISO 3200 matches shadow noise at ISO 200 pushed four stops in post, and the ISO 200 file still holds every highlight the ISO 3200 file clipped. That match holds all the way down to ISO 200; below it, at ISO 100 and ISO 50, the same push comes out noisier instead. Measured with two independent tests, dark frames and a real scene, and the answer settles into a simple rule: ISO 50 when there's enough light, ISO 200 when there isn't.
  • Expose to the Right on the X2D II: Add Light, Not ISO: Exposing to the right still pays on the X2D II when the extra brightness is light, a longer shutter or a wider aperture. Raising ISO to fill the histogram leaves the shadows unchanged from ISO 200 up and costs a stop of highlights per stop. Bill Claff's published read-noise and dynamic-range data corroborate the ISO 200 gain switch and settle ISO 100's place (none): shoot ISO 50, or ISO 200 and up. Also why a histogram cannot show small highlights, why the X2D II has no overexposure warning in Live View, and the order the author sets an exposure in.

Hasselblad lenses and optics

The XCD lineup spans three generations (V, P, E) with overlapping specs, leaf-shutter behavior, and pricing that confuses anyone building a kit. This cluster covers what each lens actually is, how the generations differ, and the operational consequences of shooting medium format through them: diffraction, equivalence, sync speeds, and which lenses pair with which X-System body.

  • The Hasselblad XCD Lens Guide: V, P, E, and Everything Else Explained: Complete guide to all 18 Hasselblad XCD lenses. V, P, E naming decoded, specs compared, filter sizes, flash sync speeds, and kit recommendations.
  • Aperture, Equivalence, and Diffraction on Medium Format: Circle of confusion, equivalent aperture, and the per-lens diffraction threshold for XCD V-series, Sigma 300-600/4 Sport, and Leica APO Summicron 43. Worked examples from a Tuscany workshop.
  • Hasselblad XCD 35-100E vs the V Primes: I Owned Both and Chose Twice: The recurring zoom-or-primes decision, answered from double ownership: bought the 35-100E, sold the primes, reversed the trade, sold both E zooms. Spec table from the lens guide, the 1.3-stop aperture math, the weight and filter economics, and a decision framework keyed to the light you actually shoot in rather than the spec sheet.
  • XCD 25V Diffraction Test: Sharpness Holds Through f/8 on the X2D II: Sixteen apertures, two full runs, and a slanted-edge target settle where diffraction actually costs the XCD 25V resolution on the X2D II. The plateau runs f/5.6 to f/8 (98% of peak), f/11 keeps 86%, f/16 keeps 72%, and by f/27 the measured curve sits on the diffraction-only limit. Corrects an earlier claim on the aperture-equivalence physics page that f/8 already cost per-pixel detail on the V primes.
  • What the Airy Disk Is, and Why a 100 MP Sensor Cares: The plain-language companion to the diffraction test. What the spot is, the one-line formula, how big it gets on the X2D II at each stop, and why 3.76 µm pixels see it from f/5.6 while 24 MP full-frame pixels wait until about f/9. Two diagrams.

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: The Complete Guide to HNCS HDR in Phocus: Hub page for the HDR series. Covers the architecture of HNCS HDR (decide HDR vs SDR in post, not at capture, unlike Canon or Sony), output formats, display requirements, and archival considerations end to end.
  • 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.
  • Do You Need RAW+JPG Capture Mode for HDR on the Hasselblad X2D II?: The in-camera HDR toggle confuses most X2D II shooters into running RAW+JPG when RAW-only would do. The toggle only controls in-camera JPEG output; the RAW captures full dynamic range regardless and Phocus can render HDR from any 3FR or FFF. Includes the full grayed-out toggle table and the three real reasons to keep the toggle on.
  • Why your X2D II files look better on iPad than iPhone: X2D II files look meaningfully better on iPad than iPhone, despite the iPhone’s higher pixel density (460 PPI vs 264 PPI). The cause is angular extent and the human contrast sensitivity function, which peaks at 3 to 5 cycles per degree of visual angle. Display tech (Reference Mode, XDR brightness) is a smaller secondary effect. Practical takeaways for review and culling included.
  • Where the Ultra HDR JPEG Preset Went in Phocus 4.2: Phocus 4.2 removed the two dedicated UltraHDR JPEG presets, but the format is now automatic: any JPEG export of an HDR-mode image embeds the gain map. ExifTool evidence (Display P3 base, full resolution, four stops of gain-map headroom), the new SDR/HDR profile model, and the explanation Hasselblad buried in a tooltip.
  • X2D II Clipping in Phocus: Why the Histograms Disagree: Record mode, in-camera playback, and Phocus are three different renders of one RAW, and only Phocus renders the file. Covers why HDR mode's forced Smart Metering makes the Phocus render darker on purpose, and why unchecking HDR in Phocus makes it report more clipping rather than less.

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.

Release announcements

Short-form posts noting new Phocus, Phocus Mobile, XCD lens, and X2D II camera 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.

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.