After my recent exchange with @Morintari on 3D images, I’ve started to look more into PMNG Stereo Drawing.
As I’ve mentioned, I’m a great fan of all things 3D and have been creating anaglyphs images with Photoshop since the 90’s. Here’s a 3D anaglyph website I had created back then:
So, I’m well aware of how to manually create anaglyphs in Photoshop, by working on separate color channels and offsetting images on a channel either right or left to make them appear nearer of further away.
Here follow a few consideration and questions I have regarding stereo drawing in PMNG, so hopefully @jan.cosmigo might help me better understand how to use them. Currently, the official documentation doesn’t really cover the topic in depth:
The documentation mentions:
Another approach to display stereoscopic images is to use interlacing. That means all pixel lines (scan lines) of a display are divided. Every even scan line shows pixels from the left image and every odd scan line shows pixels from the right image. The display uses a special polarization techniques and every image scan lines use another polarization. Special glasses then filter the light so that only even scan lines can be seen on the left eye and odd scan lines on the right eye.
I actually have a 3D Tv supporting stereo images via polarized lenses. Scanlines are just one of the accepted stereo formats, it also supports SBS (side by side) images/videos — either horiziontally sided, or vertically. It usually does a good job at auto-detecting the stereo input format, but you can also select it manually.
On YouTube, for example, most stereo videos are available as SBS, because it’s easier to convert SBS to anaglyph by applying color filters, whereas scanlines might require a more complex approach.
My problem right now is how to connec the PC to the 3D Tv. The Tv is too far away and has a big screen. So, even if I manage to cable it up, I’d still need to be working far away in order to properly see the screen. Also, full HD is too high a resolution to work in pixel art.
Any ideas on this? All I can think of is create the images on the PC (previewing them via anaglyph mode) and then save them on a USB pendrive and preview them on the Tv images viewer app.
I noticed that the anaglyph preview doesn’t allow to swap red/blue channels. Unfortunately, there’s no standars as to wether the red lense should be on the right or on the left, and 3D glasses are made in both formats. I have a box full of them, and most have the red lens on the right eye.
Also, blue/red is not the only option, there are also green/red glasses. So, ideally PMNG should allow to choose the lens colors and positions in the preview window.
I haven’t figured out how to save the final 3D image to file. Let’s say I’ve created a stereo image in color. Now I need to export it as both an anaglyph image and a polarized image. How do I do that?
I’d expect the anaglyph output dialog to allow me to choose the lens colors to use (ie. red/blu or green/red), to actually tweak the used colors slightly (not all lenses are equal in color) and to decide which lens goes over which eye.
The final image on disk should then be saved as we see it in the previer — i.e. both red/green channels merged together in a red/green image, all colors stripped out.
As for the polarized lenses images, I’d expect the save/export dialog to offer a variety of options:
- Interlaced scan-lines
- Side-by-side horiziontally
- Side-by-side vertically
Having worked with stereo anaglyphs in Photoshop, I’m not quite sure how the same tools and workflow for interlaced images could also work for anaglyphs. When working on anaglyphs, there are a variety of techniques, but basically you always work with greyscale colors in CYM color mode, and then start offsetting the Cyan (or Magenta) layers that you want to be further away or nearer to the observers.
Depending on the target medium, the maximum offset could be as little as 30px (for screen viewing) or a matter of cms when targetting printed material (depending on the DPI resolution).
Depending on the actual image contents, you often had to add to tweak backgrounds for the 3D displaced layers (unless transparent objects). For example, if you’re drawing a dragonfly, you must ensure that the body is always opaque (by applying some grey shade) and that the wings are transparent — see-trhough displacement enhances the 3D illusion.
In anaglyph drawing, you basically need to use as many grey shades as possible to enhance depth illusion, and try to avoid pure white and black. Also, don’t use flat colors but always use noise, dithering patterns or duotones patterns — because flat-colored areas tend to look empty in 3D space. There are many considerations regarding the choice of these patterns, for in 2D images granular textures tend to make object look further away, as dark colors do, so there’s also a wisdom on how to choose shades and noise patterns that match the object collocation on the Z axis in a stereo image.