The majority of graphics programs don’t have very visible ways of working with Alpha Channels. Photoshop is easy and straight-forward (see image below – the second red arrow shows the button to click in order to add an alpha channel), but the other primary programs differ greatly in how they handle Alphas, and some programs won’t let you create an all-black Alpha at all (a frequent requirement for Speculars). This can lead to all-white alphas being added, causing unwanted shine.
This method, tested in Photoshop Elements and various versions of Paint Shop Pro, has proved a simple and failsafe way to make simple Alphas for your standard DDS images. Unfortunately, greyscale alphas will not be possible using these methods, but only transparencies and dirt overlays use greyscale alphas.
To make an all-white alpha channel
- Select your entire image.
- Go to your Selections menu.
- Save your selection to an alpha channel (most programs offer an alpha channel as a selection save option).
To make a partially white alpha
- Select only the parts of the image you wish to add to your alpha.
- Go to your Selections menu.
- Save your selection to an alpha channel (most programs the alpha channel as a selection save option).
To make an all-black alpha (a workaround)
- Select a very tiny part of your image that is not being used (a small piece of black backdrop in one corner, for example).
- Go to your Selections menu.
- Save your selection to an alpha channel (most programs offer an alpha channel as a selection save option). Although this alpha isn’t truly black, the tiny white fragment will be in a place where it won’t make any difference to your object, and so is as good as an all-black alpha.
The above workaround works well for Photoshop users too! DDS plugins have a bad habit of deleting an all-black alpha (all-black alphas are usually unnecessary), but by adding a spot of white, you can ensure your images will keep their alpha after saving them as a DDS file.
