I followed some instructions with the button element to achieve a nice hover effect for an image. I realized, that it would be nice to have the effects we have for single images for this kind of transition:
f.e. to have a color image without a drop shadow and when I hover the image gets a filter and the shadow appears.
Maybe one day … (?)
I don’t know how many visuals there are, but nice things can be done with popups.
for example
Awesome idea. I also think, the pop-up feature is the to-go-to holy grail for solving everything 
Infortunately I would like to use it for many images, so the pop up is not as helpfull. But the idea, as said, awesome! 
Yes, a standard method can be useful for a lot of images, but I think popup gives a lot of opportunity for creativity.
By the way, if you refresh the previous link, I made a small update. (;
Also, I have previously shared a study on the use of popups. I’m sharing it again to give you an idea.
good job! i have to admit, i saw that already but wasn’t aware, it was made with popups as i haven’t known what popups were :).