I have 3 images which are of the same size and color (gray) and PPI and I want to put them in a new image together vertically. so I simply cut and drag each image to the new Photoshop document. it seems that the first image has the same color as the original image after transfer but for the second image (that is right below the first image) the color is a little reduced (lighter gray compared to the first one) and for the third image, that is right below the second image, the gray color is even lighter than the second one. can anybody tell me what should I do about this?
thanks

