LuttieHow to Edit Sony ARW Files Online (No Lightroom, No Install)
Open and grade Sony ARW RAW files directly in your browser. Works with A7, A9, A1, ZV, and FX series cameras. No software required.
Sony's ARW format packs full sensor data from cameras like the A7 series, A9, A1, ZV-E1, and FX3 — but most online tools either can't open it or just convert it to JPEG without any grading control. Luttie decodes ARW files directly in your browser and gives you a full color grading environment: curves, color wheels, HSL secondary, LUT application, and .cube export.
No Lightroom. No Capture One. No download.
Supported Sony Camera Formats
Luttie supports ARW files from:
- Sony Alpha — A7C, A7C II, A7 III, A7 IV, A7R V, A7S III
- Sony Alpha 9 / Alpha 1 — A9, A9 II, A9 III, A1
- Sony Cinema Line — FX3, FX6, FX30
- Sony ZV series — ZV-E1, ZV-E10 II
- Older Alpha bodies — most ARW-producing Sony cameras going back to the A200 era
If your camera writes .arw files, Luttie can open them.
Step 1 — Open the Editor
Go to luttie.app/editor. You'll need a Pro subscription to open RAW files.
Step 2 — Drop Your ARW File
Drag your .arw file onto the upload zone, or click to browse. Luttie decodes the full-resolution sensor data — this takes a few seconds depending on file size. A progress message shows while the file loads.
Once loaded, you'll see:
- Your image on the canvas at full resolution
- A metadata strip below the canvas showing your camera model, ISO, aperture, shutter speed, focal length, and resolution
- The full grading panel on the right
Step 3 — Set White Balance
Sony ARW files carry the in-camera white balance reading. By default, Luttie uses Camera WB — the white balance your A7/A9/FX body recorded at the time of capture.
If the camera WB looks off (common in mixed lighting or when using a preset that wasn't dialed in), switch to Auto WB using the toggle in the metadata strip. Luttie re-decodes the file using an algorithm-derived white balance that often handles tricky lighting more neutrally.
You can switch between Camera WB and Auto WB any time without re-uploading.
Step 4 — Grade the Image
Sony ARW files have significantly more dynamic range than JPEGs — typically 13–15 stops on modern Alpha bodies. Use this headroom:
Basic Correction
- Exposure — you have real latitude here. Shadow recovery on Sony sensors is exceptional
- Whites — pull back if highlights are bright; ARW holds more than it looks
- Blacks — lift slightly for a matte look, or push down for deep shadows
- Temperature / Tint — fine-tune the WB after decoding
Curves
Use the master curve to set your overall tonal response. For a filmic look, slightly lift the black point (raise the bottom-left anchor) and roll the highlights (ease the top-right anchor down). Sony sensors render very cleanly in the midtones — a gentle S-curve goes a long way.
Individual R, G, B curves let you shift the color of specific tonal ranges without affecting the whole image.
Color Wheels
Push the shadows toward cool or teal, pull midtones warm. The Lightness slider under each wheel controls the lift or crush of that tonal range — click the number to type an exact value.
HSL Secondary
Sony sensors render skin tones particularly accurately in ARW. The HSL secondary lets you protect or shift specific hue ranges — useful if a color grade is pulling your subject's skin in the wrong direction. Use the eyedropper to sample directly from the canvas.
Step 5 — Check the Histogram
The histogram above the Basic Correction panel updates live as you grade. Watch the edges: if either wall is clipped hard, you're losing information. Sony ARW has enough latitude that you rarely need to clip either end.
Step 6 — Apply a LUT (Optional)
If you have an existing .cube LUT, drop it into the Custom LUT zone in the Creative section. The LUT applies on top of your basic correction and curves — the correct order for technical + creative grading.
Luttie also has built-in presets in the Creative section: Classic B&W, Warm Golden Hour, Cinematic Teal, and others. These are starting points — dial in basic correction first, then apply a preset.
Step 7 — Export
Export PNG or Export JPG from the bottom of the panel for full-resolution output.
On Pro, Export LUT (.cube) bakes your entire grade into a portable LUT you can apply to other Sony ARW shots in Resolve or Premiere without regrading each one manually.
Step 8 — Save Your Project
Before closing, hit Save project in the amber banner at the top. Your grade settings are stored in the browser — reopen Luttie, load the project, and everything is exactly where you left it.
Why Shoot ARW Instead of JPEG?
ARW files give you 12–14 bit color depth versus JPEG's 8 bits. That translates directly to:
- Highlight recovery — pull back blown skies or windows
- Shadow recovery — lift underexposed areas without color noise
- White balance flexibility — change WB in post without quality loss
- Grading headroom — push contrast and saturation without banding
Once you've graded an ARW file and seen how much you can recover versus a JPEG, it's hard to go back.
Open a Sony ARW file in the editor →
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