Making an image partly transparent - Printable Version +- Gimp-Forum.net (https://www.gimp-forum.net) +-- Forum: GIMP (https://www.gimp-forum.net/Forum-GIMP) +--- Forum: General questions (https://www.gimp-forum.net/Forum-General-questions) +--- Thread: Making an image partly transparent (/Thread-Making-an-image-partly-transparent)

Making an image partly transparent - tm2383 - 09-04-2017 Hi there. Can someone who is an expert with Gimp help me with a problem? I have pasted an image of an iridology chart below. I want to remove the white from this image altogether, so that the white layer is totally transparent. When I overlay this on the image of an iris, I will therefore be able to see the black lines and labels, but not the white, which will be transparent, showing the image of the eye that I have overlaid it on. Also, is there a way of changing the colour of the black lines to another colour? This isn't essential, but it would be good if I could do this. If you are able to help with my question, could you give me easy directions about how to do this, as I am not a regular Gimp user. Thanks! RE: Making an image partly transparent - Blighty - 09-05-2017 A problem is that your image is not a good quality. The "white" background is a blotchy grey and the "black" is a blotchy charcoal. A better image will give better results. 1. With the Colour Select tool with a Threshold of 60, select the black foreground. Looks like this: https://imgur.com/a/0Yi9G 2. Select > Invert 3. Edit > Clear (or press the Delete key). Looks like this: https://imgur.com/623TOnw 4. Select > None 5. Set the Foreground Colour to red (or some other colour) 6. Lock the Alpha Channel, like this: https://imgur.com/BwIdjMf 7. Bucket Fill the image with the set foregound colour https://imgur.com/xY9TC7j RE: Making an image partly transparent - rich2005 - 09-05-2017 Same post a few weeks ago https://www.gimp-forum.net/Thread-Making-white-area-of-a-picture-transparent?pid=2555#pid2555