X3F to AVCHD Converter

How to Convert X3F to AVCHD Online

1. Upload Your X3F Files: Drag and drop or click "+ Add Files" to select one or many Sigma Foveon RAW (.x3f) frames from cameras like the SD15, DP2 Merrill, dp0/1/2/3 Quattro, or sd Quattro H. Batch upload is supported — every selected file becomes a frame in the output video.
2. Pick Merge Strategy and Image Duration: Choose "Merge images" to render one AVCHD slideshow from all frames in upload order, or "Video per image" to emit a separate AVCHD clip per X3F. Set Image Duration to how long each frame holds on screen — common picks are 1, 3, 5, or 10 seconds.
3. Set Quality, Resolution, and Background (Optional): Quality Preset goes Lowest → Very High; "Very High (Recommended)" maps to a low CRF for crisp output. Pick a Preset Resolution (1080p / 1440p / 2160p) or leave "Keep original" to inherit each X3F's native pixel grid (often 4704×3136 for Merrill bodies, 5424×3616 for Quattro H). Background Color (default Black) fills any letterbox bars when the frame aspect differs from the target resolution.
4. Convert and Download: Click Convert. Files process in your browser session — no sign-up, no watermark, no upload to a third-party server.

Why Convert X3F to AVCHD?

X3F is Sigma's proprietary RAW container for the Foveon X3 sensor, which stacks red, green, and blue photosites vertically instead of using a Bayer mosaic. The result is rich per-pixel color data — but it also means almost nothing outside SIGMA Photo Pro, Adobe Camera Raw (older bodies only), and a handful of dedicated viewers can open the file. AVCHD, jointly developed by Sony and Panasonic and introduced in 2006, is the consumer-camcorder standard that most Blu-ray players, AVCHD-compatible TVs, and editors like PowerDirector and Vegas Pro ingest natively. Rendering your Foveon stills into an AVCHD slideshow makes them playable on hardware that would never read a RAW.

• Camera-club projector loops — Many camera-club projectors and venue Blu-ray players accept AVCHD on SD card or USB but reject RAW. Drop 30-50 Foveon portraits into a single .mts at 5 seconds per frame for a hands-off review reel.
• Family TV slideshows on Sony/Panasonic gear — Sony BRAVIA, Panasonic VIERA, and most 2010+ Blu-ray players natively decode AVCHD (H.264 + AC-3 in M2TS). USB-stick playback "just works" without conversion on the TV side.
• Editorial b-roll for AVCHD timelines — When the main project is shot on a Sony HDR-CX or Panasonic HC-X1500 camcorder, dropping Foveon stills into the timeline as matching AVCHD clips avoids transcoding round-trips and keeps the edit codec consistent.
• Long-term archival in a playable container — X3F readers are dwindling; SIGMA Photo Pro has not seen major Mac updates since macOS Mojave. A 1080p AVCHD render preserves the look as a video any consumer device can still open.
• Client deliverables under tight upload limits — A 30-frame AVCHD slideshow at 18-24 Mbit/s typically lands well under a 2 GB WeTransfer free-tier ceiling, where 30 raw .x3f files (often 40-60 MB each) would not.
• Time-lapse from Sigma intervalometer captures — Use 1 second per frame (or shorter via custom duration) to turn an interval shoot into a watchable lapse without exporting to TIFF and re-encoding in a separate tool.

X3F vs AVCHD — Format Comparison

Quality Preset Quick Guide

CRF values are H.264 standards in the broadly accepted "visually lossless ≈ 18, transparent ≈ 23" range — your final bitrate is also capped by the AVCHD profile (up to 24 Mbit/s for AVCHD 1.0, 28 Mbit/s for AVCHD 2.0 Progressive).

Frequently Asked Questions

Why would I turn a Sigma RAW into a camcorder video format?

Because hardware playback. X3F is a still RAW that requires SIGMA Photo Pro or a compatible camera-RAW plugin to even open; AVCHD is the format Blu-ray players, AVCHD-compatible HDTVs, and most consumer editors decode natively. If the end goal is to play Foveon stills on a TV, project at a camera club, or drop them into a timeline already shot on a Sony or Panasonic camcorder, rendering to AVCHD removes every "what opens this?" friction point.

Will the converter preserve the full Foveon color depth?

Not fully — AVCHD's H.264 video is 8-bit per channel 4:2:0 chroma, while a Foveon X3F captures roughly 14 bits per stacked photosite. You will see the sensor's signature color separation, but subtle low-light gradations and deep-shadow color that X3F preserves get clipped to 8-bit when re-encoded as H.264. For archival-grade color, export to 16-bit TIFF or DNG first and use that as the master.

What resolution should I pick — Keep original or 1080p?

For TV and Blu-ray playback choose 1080p, since the AVCHD spec maxes out at 1920×1080 and players will downscale anything larger anyway. "Keep original" is useful when you intend to re-encode the .mts later in a desktop editor and want the source frame intact, but be aware that pushing a 5424×3616 Quattro frame through an H.264 encoder at AVCHD bitrates can soften fine detail — encode at native res only if your editor will resample later.

Can I add music or narration to the slideshow?

Not in a single pass. This tool generates the AVCHD video frames + a silent (or LPCM-empty) audio track. To add a soundtrack, render the AVCHD here, then drop it into a free editor (DaVinci Resolve, Shotcut, or Vegas Pro) and lay an audio track underneath. Alternatively, convert the result to MP4 first via AVCHD to MP4 for editors that don't ingest .mts cleanly.

How do I burn the result to a playable AVCHD disc?

The AVCHD spec defines the folder structure (BDMV/STREAM/*.mts, BDMV/PLAYLIST, BDMV/CLIPINF, etc.) that compatible players look for on DVD-R, BD-R, or SD card. This converter outputs the raw .mts/.m2ts video stream; to author a player-ready disc, use a free tool like multiAVCHD or tsMuxeR to wrap the .mts in the correct BDMV folder tree, then burn the structure to disc with ImgBurn or your OS's native burner.

Why does my output look soft compared to the original X3F?

Three usual suspects: (1) AVCHD's 8-bit 4:2:0 chroma subsampling discards three-quarters of the color resolution the Foveon sensor captured; (2) H.264 at consumer bitrates (under ~24 Mbit/s) applies macroblock-level compression that smooths high-frequency detail like fine fabric or foliage; (3) if you let the encoder downscale a 5424×3616 Quattro frame to 1920×1080, the resampling itself costs sharpness. Bump Quality Preset to "Very High" or "Highest" and pick 1080p (not 1440p/2160p — AVCHD doesn't officially support those) for the best balance.

Are my files uploaded anywhere?

Conversion runs in your browser session and files are not stored long-term on third-party servers. There's no sign-up, no account, and no watermark on the output. For Sigma owners who shoot client work under NDA, this matters — a typical 30-frame X3F batch never leaves the temporary processing pipeline.

Can I convert just one X3F into a short AVCHD clip?

Yes. Upload a single .x3f, set Image Duration to your desired clip length (e.g., 5 seconds), pick "Video per image" or "Merge images" — both produce the same result for a single input — and the converter renders a one-frame .mts of that length. This is handy for creating intro/outro stills, color bars, or test patterns at exact durations.

What if I just want the still image as a JPG or PNG instead?

If you don't need video at all, the simpler workflow is to demosaic the Foveon RAW directly to a still format: X3F to JPG for shareable web images, X3F to PNG for lossless web/print, X3F to TIFF for full 16-bit archival, or X3F to MP4 if you want video in an MP4 container instead of AVCHD's .mts.