How to make your own Anaglyphs

There are websites explaining how to do this - find them with Google - but here's how I did it.

Photo-editing Software

You need photo-editing software that gives you access to the colour channels. A very good one is GIMP, free open-source software that you can download from www.gimp.org
The instructions below are based on using GIMP 2.8.

Take your Photos

Pick an object or scene that has some depth - some parts closer to you. I chose a huge aloe - see below.
If your camera has a "grid" setting, turn it on - it's useful.

Take the first photo (for the left-eye view).

Take a small step to the right - about 6cm, the distance between your eyes - holding the camera steady, at the same level, without turning it.
Take the second photo (for the right-eye view).

Transfer the Photos to your Computer

Transfer the photos to your computer, and give them sensible names, e.g. AloeLeft and AloeRight.

Open GIMP

Make sure you can see:
* the Toolbox - if not, click Windows -> New Toolbox;
* the Tool Options - if not, click Windows -> Dockable Dialogues -> Tool Options;
* the Layers window - if not, click Windows -> Dockable Dialogues -> Layers.



Move the Toolbox and Tool Options and Layers windows off to the side from the main screen.
Open both your photos in GIMP.

Transform both Photos to Black-and-White

For each photo:
In GIMP, select Image -> Mode -> Grayscale.
All the colour will disappear, and the image will be black-and-white.
We need to fiddle with colour just now, so select Image -> Mode -> RGB to allow us to do this. The photo will still look black-and-white.

Make the Left Photo red

Do this by selecting Colors -> Levels.
The Levels window should open.
Select Channel Green.
Move the slider for Output Levels down to zero.
Your photo should now look purple.



Select Channel Blue.
Move the slide for Output Levels down to zero.
Your photo should now look red.
Click OK.

Make the Right Photo Blue

Do this by selecting Colors -> Levels.
The Levels window should open.
Select Channel Red.
Move the slider for Output Levels down to zero.
Your photo should now look blue. Actually, it's cyan (blue+green), which is what we want.

Merge the two Photos

In the right-eye photo (the blue/cyan one):
Click Select -> All.
Click Edit -> Copy.

In the left-eye photo (the red one):
Click Edit -> Paste.

Look at your Layers window - it should have a "floating layer" showing, above the layer that has your left-eye photo.
In the Layers window, click on the Opacity value (which would be 100), and change it to 50. This is so you can see both layers.

Line up the two Photos

Click the select tool in the toolbox - you won't be able to continue without this tool selected.
Your right-eye photo is floating - you can move it. It will "anchor" (stop floating) when you click somewhere off the image. Don't anchor it until you are happy with the line-up.
If you accidentally anchor it, do Edit -> Undo Anchor Floating Selection.

Click on the photo to grab it.
Pick something in the photo to line them both up on - I chose the dead branch in the middle of the aloe.
Shift the blue photo around until you've lined them up.
Now click off the side of the image to anchor the right-eye (blue) photo.

Neaten it up

Trim the extra bits of red and blue from the edges by selecting the part you want to keep - click and drag the selection tool into a box.
Then click Image -> Crop to Selection.

Save

When you do File -> Save in GIMP, it will keep a GIMP-format project (a .xcf file).
You will also need a jpg or png of your photo - do this with File -> Export.
There's a button at the bottom of the File Export window that lets you select file-type.

View the Results

View it through a red/blue (which is often more correctly called red/cyan), with the red eyepiece over your left eye.
It takes a bit of practice to do this, so be proud of yourself if it looks good!

Here's the finished Aloe photo: