Anaglyph 3D Image Maker
Combine a left-eye and a right-eye photo into a red-cyan anaglyph you can view with 3D glasses, or into a cross-eye or parallel stereo pair. Auto-align the views, fine-tune depth and download the result. Your photos never leave your device.
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Red lens over the LEFT eye. Fine-tune Horizontal shift to move the scene in front of or behind the screen.
How to use the Anaglyph 3D Image Maker
- Take two photos of the same scene: one, then step about 6.5 cm (2.5 in) to the right and take the second, keeping the camera level.
- Add them: the first photo goes in Left-eye, the second in Right-eye. You can also drop both at once, split a side-by-side image, or open an MPO file.
- Align: the tool auto-aligns on load. Use Vertical shift and Rotation to remove any up/down mismatch, then Horizontal shift to set the depth.
- Pick an output: Anaglyph for red-cyan glasses (Dubois gives the least ghosting), or Cross-eye / Parallel for viewing without glasses.
- Download the 3D image as JPG or PNG and view it with the red lens over your left eye.
How a red-cyan anaglyph works
Your brain judges depth from binocular disparity: each eye sees the world from a slightly different position, so nearby objects shift more between the two views than distant ones. An anaglyph packs both views into one picture by color. The left-eye photo goes into the red channel and the right-eye photo into the green and blue channels, which together make cyan. Through glasses with a red filter on the left eye and a cyan filter on the right, each eye sees mostly its own view and the brain fuses them into one 3D scene.
The tool builds every output pixel as a weighted sum of the left pixel (Lr, Lg, Lb) and right pixel (Rr, Rg, Rb). Luminance (Y) uses the Rec. 601 weights Y = 0.299 R + 0.587 G + 0.114 B.
| Method | Output red | Output green / blue | Color | Best for |
|---|---|---|---|---|
| True | Y of left | 0 / Y of right | None, dark | Classic look, very low ghosting |
| Gray | Y of left | Y of right / Y of right | None | Photos with strong reds or blues |
| Full color | Lr | Rg / Rb | Most | Muted, natural colors |
| Half color | Y of left | Rg / Rb | Partial | Reducing red rivalry |
| Optimized | 0.7 Lg + 0.3 Lb | Rg / Rb | Partial | Faces and warm tones |
| Dubois | 3×3 least-squares matrices for each eye (E. Dubois, 2001) | Good | All-round default, least ghosting | |
Tips for shooting your own 3D photos
- Use the "cha-cha" method. With one camera, take the left photo, shift your weight to the right foot (about 6 to 7 cm for normal scenes) and take the right photo. Keep the camera level and pointed the same way; do not twist it toward the subject.
- Match the base to the distance. A common rule of thumb is a stereo base of about 1/30 of the distance to the nearest object: 10 cm for a subject 3 m away, a few meters for a distant landscape, a few millimeters for close-ups.
- Choose still subjects. Anything that moves between the two shots (people, leaves, water, clouds) shows up as ghosting. Phones with two cameras or a 3D camera avoid this.
- Keep settings identical. Lock focus and exposure so both photos have the same brightness and sharpness.
- Remove vertical error first. Eyes tolerate horizontal disparity but not vertical: even a few pixels of up/down mismatch causes eye strain. Fix it with Vertical shift and Rotation before setting depth.
- Mind the window. Objects cut by the picture edge should sit at or behind the screen; set Horizontal shift so the nearest edge-touching object lines up exactly.
Anaglyph vs. cross-eye vs. parallel
| Format | Layout | How to view | Pros | Cons |
|---|---|---|---|---|
| Anaglyph | One image, red + cyan | Red-cyan glasses, red on left eye | Easy for anyone with glasses, works at any size and in print | Colors are altered, some ghosting |
| Cross-eye pair | Right view left, left view right | Cross the eyes until the images merge | Full color, no glasses, works for large images | Takes practice |
| Parallel pair | Left view left, right view right | Relaxed "look through" gaze, stereoscope or VR viewer | Full color, the format most viewers expect | Free-viewing only works if each view is smaller than about 6.5 cm wide |
Frequently asked questions
How do I make a 3D anaglyph photo?
Take two photos of the same still scene from positions about 6 to 7 cm apart horizontally (the distance between human eyes). Load the left one as the left-eye image and the right one as the right-eye image, press Auto-align, and download. The left view is put in the red channel and the right view in the green and blue (cyan) channels, so each eye sees only its own picture through red-cyan glasses.
Which eye gets the red lens?
Standard red-cyan glasses have the red filter over the left eye and the cyan filter over the right eye, and this tool follows that convention. If the depth looks inside out (near things look far), your glasses are reversed or the photos are swapped: press Swap L ⇄ R.
Which anaglyph method should I choose?
Dubois is a good default: it uses matrices calculated by Eric Dubois to reduce ghosting with typical red-cyan glasses while keeping some color. Full color keeps the most color but can cause retinal rivalry on red objects. Half color and Optimized reduce that rivalry. Gray and True anaglyph give the cleanest depth with no color, which is best for photos with strong reds or blues.
What does Horizontal shift do?
It moves the right image sideways relative to the left one, which changes where the scene sits in depth. Whatever lines up exactly appears at the screen surface; things with more separation appear in front of or behind it. A good rule is to put the nearest object at or slightly behind the screen and keep the total depth range modest so the image is comfortable to view.
Why do I see double images or ghosting?
Ghosting comes from color leaking through the wrong lens or from a vertical misalignment. Try the Dubois or Gray method, make sure Vertical shift and Rotation remove any up/down difference, and avoid very large depth: for an image viewed on a screen, keep the left/right separation of the farthest and nearest points within a few percent of the image width.
Can I use a side-by-side 3D image or an MPO file?
Yes. Choose the layout (side-by-side, cross-eye or over-under) and press Split stereo image / MPO to cut one image into two views. MPO files from 3D cameras store two JPEG pictures in one file; the tool reads the MP index and loads both automatically.
How do I view the cross-eye or parallel pair without glasses?
For a cross-eye pair (right view on the left), hold the screen at arm's length and slowly cross your eyes until the two pictures overlap into a third, sharp 3D picture in the middle. For a parallel pair (left view on the left), relax your eyes as if looking through the screen, or use a stereoscope or phone VR viewer. Keep parallel pairs small, since eyes cannot diverge beyond about 6.5 cm.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.