How to interlace in Photoshop

There are many interlacing software applications available on the market. Click here to see our software site.

However, interlacing images with only Adobe Photoshop works just fine, and is not complicated once you know the procedure.

Here is how it’s done:

For a flip


Opening the images


  1. Scale the images to the required size.

  2. Copy one of the images, then “paste” it as a layer in the other file.

  3. Create a third empty layer and name it: “pattern mask”.

  4. On this layer, we will create a mask, which will alternatively cut and save half a lens of information from one image and block information from the other image.

  5. If the optical pitch is 75.54 LPI; you must scale your file to the final size (including bleed) to 151.08 dpi (75.54 LPI x 2 images).


Creating the “Mask”


  1. Create a new file from the menu and give it any name (don’t open it yet).

  2. Set the “Width” and “Height” to 2 pixels (corresponding to the number of images you are interlacing)

  3. Set the resolution to 151.08 PPI. It must correspond to your final interlaced file.
    Formula = pitch (75.54) x number of images (in this case 2)

  4. Use the color mode you are using for your images.

  5. Select “white” content.

  6. Then “OK” to finalize the file.


Creating the “Pattern” in this new file


  1. Zoom to the maximum and use the selection tool (“Marquee tool”), select one pixel line or column (horizontal is better for flip and vertical is mandatory for 3D)

  2. Fill this selection in black: in the menu bar go to: “Edit”–> ”Fill” and select “Black” from the “Content” dropdown menu.

  3. Our “Pattern” is ready: “Select All”, in the menu; choose “Edit”–> “Define Pattern” and save this with a name like “Flip 2 horizontal”.


Back to interlacing


  1. In your image file (in layers) go to the layer named “pattern mask”. In the menu: ”Select”
    –> ”All”, then in menu again: “Edit” –> ”Fill” for “Content” choose “Pattern” and choose the “Pattern you just made. This will fill the layer with the selected “Pattern”.

  2. Turn this grid into a selection: in the menu “Selection” –> “Color Range” select “Shadows”, this will select the black lines.

  3. Save the selection: menu “Selection” –> “Save Selection”. Give it a name i.e.: “Mask”

  4. Go to your first “Layer”; in the menu “Layer” –> “Layer Mask” –> “Reveal Selection”. This will reveal the image information sitting behind the selection (half a lens).

  5. Go back to your layer “pattern mask” and move it for one pixel and repeat step “d” on the second image layer. This will fill the other half lens with image 2.

  6. Flatten your result and it is ready to output.


You will use the same procedure for any amount of frames to be interlaced, the only difference is you will be repeating the last steps  4 and 5, (from the last part “Back to interlacing”) the number of times equal the number of layers used.

Don’t hesitate to contact us if you have any question about the above procedure.