Caduceus

Caduceus is a set of open-source firmware patches for the Olympus PEN E-P7 (firmware 1.1). It adds film simulations you pick and edit in the camera, per-colour hue and lightness, bloom, clarity and Art Effects on your colour profiles, B&W film presets, true log video, XPan and 21:9 stills, and longer video recording.

Named after the caduceus, the staff of Hermes: messenger between gods and mortals and guide of travellers.

Latest release: v0.23 · Install guide · Changelog · Caduceus Control Panel (make and share looks in your browser) · The camera's Setup › Firmware screen shows the Caduceus version.

Warning

Early development, use at your own risk. Caduceus is unofficial, experimental firmware modification. Bugs will turn up, and flashing modified firmware can crash, freeze or brick your camera, corrupt photos or damage your SD card's data. The author accepts no responsibility for any damage, data loss or other harm to your camera, cards, files or anything else. It is provided "as is", without warranty of any kind (see the Apache License 2.0, sections 7–8). Using it may affect your warranty with OM Digital Solutions.

Every patch is checked in an emulator of the camera's CPU before it goes on a camera, the SD update and restore path is proven on a real E-P7 (including recovery from a bootloop), and features marked camera-tested below have run on a real camera. Read Safety before flashing.

Features

Feature	What you get	Status
Film simulations	29 colour looks in EP7MOD/LOOKS.BIN: Velvia, Astia, Classic Chrome, Classic Neg, Nostalgic, Reala Ace, Eterna, Bleach Bypass, Kodachrome 25 and 64, Portra 160 and 400, Ektar 100, Gold 200, Ektachrome, UltraMax 400, CineStill 50D and 800T, Vision3 250D and 500T, Pro 400H, Fujicolor 200, Cuban Neg (inspired by Osan's Classic Cuban Neg), Agfa Vista, Cibachrome, Polaroid, Cross Process, Atrophy (inspired by [Gx]Ace) and Faux IR (an infrared-inspired false-colour look). Pick one per Colour Profile slot; its name shows in Picture Mode.	Camera-tested
On-camera look editor	The stock Colour Profile wheel gains pages: Saturation, Hue, Light, Film and Extras (INFO cycles). The wheel follows the page; modified looks are marked *.	Camera-tested
Looks on the SD card	Looks load from EP7MOD/BUNDLES.BIN on the first half-press. Edits made in the camera save back to the card (with a .BAK of the previous file).	Camera-tested
Tone per look	Every film look carries its own tone curve: Highlights, Midtones and Shadows (applied through the camera's own tone control) plus new Blacks and Whites that move the very ends of the curve (crushed slide-film blacks, faded instant-film blacks, rolled-off negative highlights). Picking a look applies it; Blacks/Whites are also adjustable per profile (Extras 6/7). Shown in live view too.	New in v0.20
LCD colour fix	The rear screen no longer looks slightly pink (+8 % green by default), and Monitor Adjust's colour slider becomes a green ↔ magenta slider (−7..+7, about 2.3 % per step) instead of warm/cool. Display only: photos, movies and HDMI are unchanged.	New in v0.20
Extras per profile	Bloom ↔ clarity (one slider), WB amber/blue and green/magenta shift, and Art Effects (Star Light, Pin Hole; Blur removed in v0.21, it could restart the camera).	Camera-tested
Noise reduction per look	Each colour look can set the camera's own noise reduction (Noise Filter). Less noise reduction keeps the sensor's natural fine texture instead of smoothing it away. Extras sector 1 NR: Camera (leave the camera's setting alone), Std, Low or Off (most texture). It is set when you pick a look or change sector 1. The Noise Filter is one camera-wide setting, so it stays at the last value when you switch to another profile. The difference shows mostly at higher ISO. True film grain is on the roadmap (the camera's grain stages add nothing visible to colour photos).	✅ v0.22
Mono film presets	Pan F 50, Acros, T-Max 100, SFX 200, Tri-X 400, HP5 Plus, Delta 3200, Sepia Print, Selenium, Cyanotype for Monochrome Profiles, built from OM's own mono settings. Label <name>, * when modified.	Camera-tested
Live-view preview	Hue, lightness and bloom show in live view, not only in the saved photo.	Camera-tested
True log video	A log curve Olympus left hidden in the firmware, switched on with the movie picture mode set to Muted.	Camera-tested
XPan 65:24 and 21:9	Panorama (5184×1920) and Wide (5184×2224) in the menu and Super Control Panel, with matching live view and playback framing and XPAN/UW size labels. Boots back to 4:3 each power-on, for safety.	Camera-tested
Recording limit	29-minute and 2-hour caps raised to 9 hours (file, chapter and heat limits still apply).	Camera-tested

Install

You need: an E-P7 on firmware 1.1 (check Setup › Firmware), a fully charged battery, an SD card, and a computer with Python 3.10+ (Windows, macOS or Linux).

1. Get Caduceus

On this page click Code › Download ZIP and unzip it (or git clone the repo).

2. Build the update file on your computer

OM's licence doesn't allow anyone to share their firmware, so the update file is made on your own computer. The builder downloads OM's official 1.1 firmware from OM's server, checks it, and applies the Caduceus patches.

• Easiest: in the unzipped folder, double-click the launcher for your system:
  • Windows: Build Caduceus (Windows).bat
  • macOS: Build Caduceus (Mac).command (the first time: right-click › Open)
  • Linux: build-caduceus-linux.sh
• Or from a terminal in that folder: python3 caduceus.py build --release v0.23 (Windows: py caduceus.py build --release v0.23).

It creates a folder with:

DCOLYMP/E1429999.BIN   the patched firmware update      → goes on the SD card
EP7MOD/                the film looks and your slots      → goes on the SD card
restore/E1429999.BIN   the original stock firmware        → keep on your computer (to undo Caduceus)

3. Copy to the SD card

Put the camera's SD card in your computer and copy the DCOLYMP and EP7MOD folders to the top level of the card (next to the DCIM folder). The launcher offers to do this for you. Eject the card properly.

4. Flash the camera

1. Put the card in the camera. Battery fully charged, camera off.
2. Hold the OK button and switch the camera on. Keep holding OK until the status light comes on.
3. The light stays steady while the update is written (it can take as little as 10 seconds). Do not switch off, open the battery door or remove the card.
4. When the light starts blinking (about twice a second), it's finished. Switch the camera off.
5. Switch it on normally. Setup › Firmware now shows Caduceus and the version.
6. On a computer, delete DCOLYMP/E1429999.BIN from the card (keep EP7MOD: that's where your looks live).

If the light blinks fast straight away with no steady phase, the camera rejected the file and nothing was written. Rebuild and copy again.

5. Shoot

Switch on, half-press the shutter once (that loads the looks from the card), then open a Colour Profile and press INFO to reach the Film page. See Using it.

Undo / go back to stock

Copy restore/E1429999.BIN from your computer to the card as DCOLYMP/E1429999.BIN (replacing the patched one) and flash it exactly as in step 4. The camera is then completely stock 1.1 again.

More detail, troubleshooting and FAQ: docs/INSTALL.md.

Make your own looks: Caduceus Control Panel

Caduceus Control Panel is where you edit the built-in looks and make new presets, right in your browser:

• Tweak any look (per-colour hue, lightness and saturation, noise reduction, glow/clarity, WB shift, Art Effect), or start a new one, with a live preview on example photos or your own (your photo never leaves your browser).
• Share a look with a short code: press Share, send the code or link, and anyone can paste it into the Control Panel to get the same look.
• Export your pack as LOOKS.BIN, copy it to EP7MOD/ on your SD card, half-press, and your looks are on the camera's Film page.
• RapidRAW presets (no firmware needed): a look's Share button (or Export › RapidRAW presets) saves it as a .rrpreset for RapidRAW, the free raw editor; Export can also zip all of them, one preset per look (unzip, then Presets › Import and select the files). Use it to apply the looks to your ORF files after the shot, or to raws from any camera, so you can use the looks without a modded body. It's an approximation: RapidRAW starts from its own raw rendering, so expect the look's character rather than an exact match to the camera JPEG. Colour, tone, white balance, glow/halation, clarity, vignette and the mono filter carry over; noise reduction and Art Effects don't.
• Install firmware: the Install firmware button walks you through installing Caduceus step by step, with links to the latest release and the full guide.

Using it

On the card (copy EP7MOD from the build to the card's top level):

EP7MOD/LOOKS.BIN     the film library (the looks you can pick)
EP7MOD/BUNDLES.BIN   your 4 Colour Profile slots: which look each holds, plus your edits (the camera rewrites it)

Every time you switch on: half-press the shutter once. That loads your looks from the card (nothing is read at boot). No EP7MOD folder = the camera behaves almost stock.

Pick a film look

1. Picture Mode → a Colour Profile (COLOR1–4); its name shows in the Picture Mode list.
2. Open that profile's colour wheel, press INFO until the page shows Film: <name> (the Film page).
3. Turn the dial to scroll looks (Film: Velvia, Film: Portra 400, … Stock). Leave the editor and half-press to save.

Picking a look sets that profile's colours, noise reduction, glow/clarity, WB shift, Art Effect and tone curve. Saturation stays yours. A * after the name means you've changed something since picking it.

Fine-tune a look (same colour wheel, INFO cycles the pages):

Page	What the dial does
Saturation (· All)	stock per-colour saturation (INFO also toggles single colour / all colours)
Hue / Light	shift or brighten/darken one colour sector (pick the sector with the other dial)
Film	choose a look from the library
Extras	sector 1 NR Camera / Std / Low / Off (noise reduction) · 2 glow ← → clarity · 3 WB amber/blue · 4 WB green/magenta · 5 Art Effect · 6 Blacks · 7 Whites

Highlights/Midtones/Shadows are on the camera's normal tone-curve screen; picking a look sets them for you.

Mono film presets: Picture Mode → a Monochrome Profile → open its Colour Filter (or Shading) editor → INFO steps Pan F, Acros, T-Max, Tri-X, HP5, Delta 3200, Sepia… (name shown on screen).

Make, change or share looks: use the Caduceus Control Panel. Edit sliders with a live preview, press Share for a short code anyone can paste in, and Export a new LOOKS.BIN to copy into EP7MOD/.

Log video: in movie mode set the movie picture mode to Muted. You record the camera's hidden log curve (live view looks flat too). Grade it afterwards.

XPan / 21:9: Image Aspect (menu or Super Control Panel) → Panorama (65:24) or Wide (21:9). The camera boots back to 4:3 each time, on purpose.

Screen too pink or green? Setup › Monitor Adjust: the colour slider is now green ↔ magenta (0 = corrected).

Quick answers

• Nothing changed? Half-press once after switching on, and check EP7MOD/ is at the card's top level.
• Want stock back for a moment? Remove the EP7MOD folder. For good? Flash the restore file (see Install).
• Will updating lose my looks? No: keep your EP7MOD/BUNDLES.BIN, and just replace LOOKS.BIN and the firmware.
• Live view vs photo: Star Light and some effects only show in the saved photo.
• Black screen during Rec View on bloom/clarity looks? Known issue: the review goes dark while the effect is processed. The photo is fine: set Rec View to Auto ▶ or press ▶ to see it.
• Sector 1 "NR"? It sets the camera's noise reduction (Noise Filter), not film grain; Off keeps the most texture. It shows mostly at higher ISO, and it applies when you pick a look or edit sector 1 (switching profiles keeps the last Noise Filter value).

On-camera UI

The images below are mock-ups made on a computer to preview the features. On the camera nothing new is drawn: Caduceus reuses the camera's own screens, fonts and icons, so everything looks exactly like the stock E-P7 UI. The colour wheel gets extra pages and its guide line shows the page or look name.

Stock Colour Profile editor	Look editor (mock-up)
Image Aspect menu (mock-up)	XPan framing (mock-up)

Film looks

Recipes built only from controls the patched camera has. The previews above are from the desktop simulator on E-P7 RAW files, so the camera's JPEGs can differ slightly. Several looks are converted from community Olympus recipes (GarethB's Kodachrome 25 on mu-43.com, and om-recipes.com); sources and credits are in docs/LIBRARY_V1.md.

Make and share look packs

Use the Caduceus Control Panel: edit or create looks, share them as short codes, download LOOKS.BIN for your card, or export them as RapidRAW presets for raw files from any camera. Nothing to install. (Developers: the source is in webapp/.)

Log video

The E-P7 firmware already contains a proper log curve (about 12.4 % of output per stop) and a Flat curve: the same kind of profiles Olympus ships as OM-Log400 and Flat on other TruePic VIII bodies. On the E-P7 they are simply hidden: no menu can select them. Caduceus switches the log curve on when the movie picture mode is Muted. Left: the standard curve. Right: the hidden log curve, rendered with the firmware's own tone table.

Build on Caduceus

Caduceus is meant to be a starting point, not a walled garden. The goal is an open film-recipe community for Micro Four Thirds, the way Fujifilm shooters share film simulation recipes, but for OM/Olympus bodies. Fork it, port it, remix it:

• Port it to your camera. The patch tooling (caduceus.py, tools/build_package.py, the edit-list format and the emulator checks) is camera-agnostic. Other TruePic VIII bodies share most of the code base; see docs/PORT_EM10IV.md for what carries over to the E-M10 IV.
• Keep the shared formats. Please keep LOOKS.BIN, the look parameters and the share codes compatible (or versioned) so a look made on one project works everywhere. The format is documented in webapp/README.md.
• Use the Control Panel. Caduceus Control Panel is the common place to make, preview and share looks. Fork it for your camera, or send changes back so everyone gets them.
• Share your looks. Post the share code with a sample photo (Reddit, forums, socials); anyone can paste it into the Control Panel. Good community looks can be added to the built-in library: open an issue or PR with the code, a sample, and credit for any recipe it's based on.
• Credit and licence. Apache 2.0: use it in your own projects, commercial or not. Keep the NOTICE, credit recipe authors, and never redistribute OM firmware (ship edit lists plus a builder, like Caduceus does).

Roadmap

Grouped by how likely and how hard each item is. Feasibility notes for the video and lens items are in docs/VIDEO_HIDDEN.md.

Likely / easy

• Clean HDMI output: stock Record Mode (sid 1276) exists but is gated to movie mode at 0x60d1cb42; drop the gate.
• Per-profile "vignette correction off": stock Shading Comp. is sid 61; override it per slot like the Art Effect flag.
• Art Effect live-view preview that updates immediately.
• Rec View that shows the photo and then updates it with bloom/clarity (as stock Art mode does), instead of a black screen.
• More film looks, and a cross-platform web app to build and share LOOKS.BIN files.
• Control Panel camera selector: export the same looks for other cameras (built, hidden until other cameras have known-good builds).

Possible / medium effort

• True film grain on colour photos (the camera's own grain stages add nothing visible to colour; needs a new approach).
• Noise reduction on profile switch: re-apply the slot's Noise Filter value when a profile is selected (today it is set on a look pick or a sector-1 edit; the Noise Filter itself is camera-wide).
• ISO Auto in movie M: the movie ISO list already includes Auto; the dynamic gate in the AE code still has to be found.
• Vignette on colour profiles as Extras sector 8 (−5..+5, finer than stock), using the stock shading stage (docs/VIGNETTE.md).
• Blacks/Whites page on the camera's own tone-curve screen (today they live on Extras 6/7; docs/TONE_ENDS.md §8).
• Tinted halation (red glow around white lights), probably via a mask built from the exposure meter grid.
• Maybe: use the ART position on the mode dial as a quick "silent shutter" switch.
• Canon 1100D (Rebel T3): no firmware hack; export looks as Canon Picture Style (.PF2) files, if the PF2 checksum can be solved, else as recipe cards (docs/PORT_CANON_1100D.md).

Hard / long shot

• C4K video: hidden, not removed (C4K drive mode, 4096×2160 tables and HDMI C4K are present); the sensor, encoder and thermal setup are unknown and need camera tests.
• FHD 120p high-speed: the E-P7 only has a 720p 120 mode; this needs a new readout and encoder setup.
• Highlight-weighted metering and snap focus (Ricoh GR-style).
• Picture-in-picture focus assist (GM1-style magnified window over the full view, issue #18): no second LV window in stock; needs a second, cropped output from the LV job (docs/PIP_FOCUS.md).
• E-M10 IV port: same container and CPU, ~48 % of v0.20 edits relocate by signature, but it has no Colour/Mono profiles (looks need a new host) and no test body (docs/PORT_EM10IV.md).

Parked

• Live ND: the code exists only on E-M1-class bodies, not in the E-P7 or E-M5 III; it would mean new ISP code.
• Colour looks on Monochrome slots or extra profile slots; a list-style menu instead of the wheel; 4:3 "open gate" video.

How it works

• This repository contains no OM firmware. The builder downloads OM's official file from OM's own update server and checks its hash.
• Patches are small MN103 assembly routines and data edits. Each one has a build script that checks every stock byte it replaces, places code only in verified free space (docs/CODE_SPACE_MAP.md), and emits an edit list.
• caduceus.py (and tools/build_package.py for developers) turns an edit list into an update file for the camera's own SD updater, plus a matching stock-restore file. It refuses unexpected stock bytes, and every output must match the release's published hashes.
• Every patch has an emulator test that runs the real camera code, patched against stock, and checks that only the intended values change. Every package is checked to decode to exactly the emulated image, and its restore file to exactly stock.
• Runtime state lives only in heap memory the loader allocates; patches never write into the firmware image in RAM.
• A desktop colour pipeline (sim/), calibrated against the camera's own JPEGs, previews looks on RAW files.

Safety

• No responsibility is accepted for damage of any kind. You flash this at your own risk. This is early-development software: expect bugs.
• Only the E-P7 on firmware 1.1 is supported.
• The camera's SD updater (hold OK while switching on, file at DCOLYMP/E1429999.BIN) is confirmed working: LED steady while writing, then a ~2 Hz blink when done. It rejects corrupt files without writing, and stock firmware has been restored through it, including from a bootloop.
• A full battery and an uninterrupted write are essential. A failed write can leave the camera unbootable.
• Keep the stock restore file the builder makes (restore/E1429999.BIN). Flashing it returns the camera completely to stock 1.1.
• No EP7MOD folder on the card = almost stock. All film looks, the look editor pages, Extras and mono presets only run when EP7MOD/BUNDLES.BIN is on the card, and nothing is read from the card until the first half-press. Without the folder (or with no card in) only these small, always-on changes remain:
  • log video when the movie picture mode is Muted;
  • the extra Panorama / Wide aspect options (the camera always boots back to 4:3);
  • the longer recording limit;
  • the Caduceus version on the Setup › Firmware screen.
• If something misbehaves: remove the EP7MOD folder first. If that doesn't help, flash the restore file.

For developers

git clone --recurse-submodules https://github.com/cakelesscoder/caduceus-ep7
cd caduceus-ep7
tools/fetch_stock.sh          # downloads OLY_E_142_1100_0000_0000.BIN from OM and checks its hash
tools/setup_toolchain.sh      # GNU binutils for mn10300
tools/decode_stock.sh
python3 -m venv .venv && .venv/bin/pip install rawpy numpy pillow

Per-patch build and verify commands are in each patches/*/ folder and in WORKLOG.md. Design notes are in docs/.

Support

Caduceus is free and open source. If it brings your E-P7 to life and you'd like to say thanks, you can buy me a coffee. Bug reports and camera test results are just as welcome: please open an issue.

Credits

• Inspiration: u/fischgurke and his PEN-F HSL firmware mod, which showed an Olympus body could get in-camera HSL editing and started this whole project.
• fishcu/oly_fw_analysis: PEN-F firmware research and the MN103 emulator harness this project builds on (used as a submodule).
• LightSnowDev, Altsoph/mx3 (CHDK forum), the DVXuser and Personal View Olympus threads, and iKenndac for earlier Olympus firmware research.
• [Gx]Ace (Casey Cavanaugh, gxace.com): his videos inspired the Atrophy look and the XPan aspect ratio.
• Community film recipes: GarethB (Kodachrome 25, mu-43.com), om-recipes.com contributors; see docs/LIBRARY_V1.md. Film-look references: docs/FILM_SIMS.md and docs/FILM_LOOK.md.

License

Caduceus patch code, tools and docs are released under the Apache License 2.0. The OM firmware itself is not included or redistributed: the builder downloads it from OM's own server on your machine. The external/oly_fw_analysis submodule (developer tools only) keeps its own licence. See NOTICE.

Not affiliated with OM Digital Solutions or Fujifilm. "Olympus", "PEN" and film names are trademarks of their owners.