Using Transparency in Photoshop: .PNG Vs. .TGA

If you have ever opened up an image in Photoshop that was supposed to include a transparent background and been greeted instead by a sea of blackness you have likely encountered the frustration that comes with .tga files. However there are some good reasons to use them, but there are also some ways that you can get them back to a nice transparent background and proceed on with your work. Understanding the basic differences between .png files that can include transparency and .tga files which include transparency as an alpha channel is very important.

To start with, a .png file preserves the transparency right on the image without any additional layers, channels or work involved. However, a .tga file requires an alpha channel in order to preserve transparency and typically the alpha channel will only cover up parts of the image that are there, rather than the image including parts that are transparent. For example, a .png file with transparency would have a bow with the background transparent, while a .tga file would have an entire image of fabric, while the alpha channel is shaped like a bow so that once the alpha channel is applied, you are saving the bow and the rest is transparent.

If you happen to obtain any images or you have created any images as a .tga and you are wanting to preserve the transparency without using an alpha channel, there is help available to you. For example, if you open the .tga file and load the alpha channel then delete the remaining portions of the image, you should now have a transparent background that you can easily work with by duplicating layers, copying layers and other actions.

If this image is then saved in .png format, you do not have to worry about the alpha channel, but rather are able to proceed along with your project and begin working with different images, or pieces of the image as you were planning to do. By converting an image from a .tga to a .png file you are going to likely find that it is much easier for you to work with than you previously expected, however you should also remember that you need to still keep a copy of the original in case something happens and you need to go back to that. You never know when you might need to adjust that original image and will need the original alpha channel to work with again.