Artwork tips for lenticular printing
Using the lenticular technology, you can create images with various effects:
- 3D – three-dimensional images (sometimes called holographic);
- Flip – two or more images to be combined and viewed independently at different angles while shifting the lenticular lens or changing the point of view;
- Motion – a kind of the flip effect, but with continuous object motion from one position to another one like a short movie of several frames;
- Morphing – similar to motion, but the set of frames shows gradual transformation of one image into another one;
- Zoom – similar to the “morphing”, or “motion” effect with the gradual image object resizing.
To create different effects, you need a set of source images (frames): photographs or animated graphics. Here we give some design tips for such images
Type, size, format
Images must be raster–bitmaps (digital photos, illustrations) with the resolution of 150-350 PPI (pixels per inch).
However, there is no big sense in artificially increasing the image resolution by means of interpolation – by doing so, you will not be able to improve quality. It is better to use the image in its original resolution obtained from a designer, a photo bank or taken by photo camera.
It is advisable to use images without any traces of scanning or compression (JPEG compression) artifacts.
Preferable file formats: tiff, png, psd, jpg (with the low compression level).
If the image composition contains a number of layers (Photoshop layout), then the layers must be rasterized and not grouped; all the effects must be applied, the text must be converted to raster layers.
Do NOT use backgrounds with regular textures.
For all types of raster images, textures with periodically repetitive elements (grids, vertical/horizontal stripes, etc.) are not advisable. Keep in mind that image will overlap with the lenses, which can cause interference effects (moire, ripple, etc.)
Do NOT use serif fonts and italics. They become less clear-cut when observed through lenses.
Do NOT use artistic and complex fonts as they are harder to read through lenses.
Do NOT use small font sizes for lenticular images as the lenticular makes texts less readable.
– you will have a 3D feeling when viewing the lenticular image from the front. The 3D effect is also visible when you change the point of view to the left/right within the angle of view of the lens (usually 26-60 degrees).
There are several zones of a comfortable 3D effect. When you transit between zones, “ghosting” or shifting may occur (also known as transition effect).
Number of images: from 1 to 144 and more, depending on lenticular and printing properties.
A 3D image can be created out of various source images. Depending on the type of source data you might need corresponding further editing.
Source image types
1. One frame: a regular 2D photo or picture. 2D-3D conversion will be performed.
2. Two frames of a stereo pair (S3D). S3D-3D conversion will be performed.
3. Sequence (set) of frames from a multi-view shooting or 3D modeling (from 5-12 up to 144 frames or even more). The shooting must be performed with a horizontal shift of the camera or by means of a multiple-camera mounting, where optic axes of the cameras are parallel. The scale, focusing and color gamma of frames must be identical. The camera shift range (shooting basis) must be within 0.5 of the distance to the foreground object.
The formula for calculating the basis (B) for lenticular multiview shooting:
D – distance from the camera to the foreground object of the scene.
a – viewing angle of the lenticular lens.
4. Project (layout) – a compositional image consisting of several layers saved to a PSD file.
Use bright and light-colored images with big objects for getting a better 3D effect.
The composition of the image (scene) should look three-dimensional itself – it must contain objects placed at different distances from the viewer.
Traditional artistic techniques can help you add the 3D effect.
It is advisable that the scene have the perspective, light and shadow, which makes the objects dimensional. If objects overlap, the 3D effect will become stronger.
The logos should be placed closer to the middle plane of the image (zero-parallax plane), where they will be more vivid and readable. Avoid very light-colored lettering and serif fonts.
For the foreground and the background use non-contrast images with few details to get a better effect.
Do NOT use complex detailed images as they are difficult to view, and the 3D effect is reduced.
Do NOT use wide horizontal stripes for the background and homogeneous textures to fill large parts of the image – it will be difficult for the viewer to feel the depth.
Flip – The image is changed completely when the viewing angle is changed.
Number of images: usually 2-3.
Keep flip effects simple. You can use more than 2 frames, but it is better to take as few images as possible to get a better and clearer effect. It is better when the flip effect covers not the whole image, but only a part of it. It is better to use images with similar colors and tints when creating the flip effect.
Do NOT use the white color for the background – the “ghosting” effect might appear. Try to avoid very dark colors for the background as the animation will be less perceptible. Using high-contrast colors for the flip image, you risk getting the “ghosting” effect when 2 images are seen simultaneously, while they are supposed to clearly interchange.
Zoom – The object size is changed when the viewing angle is changed. Number of images: from 2 to 36. Use bright, solid images to get a better zoom effect. Use a separate layer for the zoom effect if you use more than 1 effect in your design. You can use the zoom effect with text and logos.
Morphing -A sequence of frames with smooth transition of objects is used for the source images. Adjacent frames should be only slightly different, while the first and the last frame of the series can differ a lot. It is advisable that the first and the last frame of the series have a similar shape and there should be some transformation concept. In this case, the result will be interesting and attractive. For example, a pumpkin transforming into a carriage is a good idea.
Do NOT use complex forms.
Number of images: from 2 to 36, or more. Similar to frames in a movie, a sequence of frames with moving objects is used for the source images. Ideally, images must be only slightly different from one another. It is better to start with movies or something of the kind for getting a smooth frame sequence. Computer graphics is also a very good choice.
Do NOT use very complex animation.
Do NOT use objects moving from one image edge to the other one. Not every sequence of frames is suitable for animation.