Transition per Image?

[BoguschMedia]

I'm in the situation where i have to use (service side) cropped thumbnails coming from another software. so i have no choice there until i have the time to build a solution. meanwhile i would love to add per image that some images should not open with zoom but with fade or none instead. is this possible? so i could eliminate the "hickup" of these few portrait thumb images that make a hickup when using "zoom". but i realy want to use zoom for 99% of the images. :-D may be with a data- attribut in the a-tag? that would be the easyest way