If I set only the "base" image watermark in the admin panel, it watermarks not only the fullscreen image but also the "medium" image used in the main product view. On the full image, the watermark is the correct size but on the medium image, the watermark covers about a third of the product image.
How can I either stop the medium image being watermarked or allow the watermark to be sized proportionally to the product image size? i.e. by setting a heightXwidth percentage instead of a pixel value.
Also, my watermark has a white background which gets converted to transparent - this is not desirable for me.