I have been fighting with image transfers these past few weeks. I know there are a million different methods, but I determined to make it work with packing tape or contact paper.
I am finding that packing tape transfers make for very transparent crisp images and the paper is very easy to remove from the back. However, it's near impossible to use any mediums on top of these transfers. If you sand the images to roughen them up a bit you can, but it still can easily be removed with the slightest pressure of a finger nail.
I'm working with magazine images from different magazines, laser prints and various book images ... color and black and white.
Contact paper transfers are proofing to be rather unpredictable and it's difficult to remove the paper from the back without actually lifting the image. The plus side of the contact paper transfers is that you can use other mediums on top ... with a slight sanding, everything seems to stick quite well.
Just yesterday I discovered a new type of contact paper and so far am having wonderful results. Grant it, I have only made 1 transfer, but so far so good! Extremely transparent, all the paper comes off the back easily AND other mediums stick to the surface. In the picture below I used a print (the text) from my laser printer and it sure seems to work. I am now off to try it with other images from magazines and books!