So I had two nearly similar images. The only difference is the object in one image is on the left side while in other its on the right side. What I wanna do is combine them both so that the final image looks like there are two objects.
- Open the first image
File>Open as layersthe second image so that it is added as a second layer
- Reduce the general opacity of the top layer (slider at the top of the layers list)
- If necessary move the top layer around so that it matches the bottom layer
- Let the top layer be transparent:
Layer>Transparency>Add alpha channel
- With the Eraser erase the top layer over the object in the bottom layer
- Make the top layer fully opaque again using the big slider (the hole will remain transparent
- If the edge of the "hole" is too visible you can soften it by setting the Eraser to a soft brush (
Hardness 025) and going over them.
More advanced technique: Layer mask instead of Eraser
As above, but instead of erasing:
Layer>Mask add layer mask, and initialize to white (fully opaque). The mask thumbnail will be added next to the layer thumbnail.
- From then on, paint applies to the mask (the status bar at the bottom says " mask" instead of just "".
- The mask is really the opacity of the layer, painting black makes the layer transparent, painting white makes it opaque, and of course grays correspond to levels of partial opacity. The advantage is that you can easily edit and correct things without having to undo the good parts.