Have you ever bought something online based on a picture, then ended up surprised by how small it was when you got it? Without a point of reference for scale, you don't know how big something is.
The idea is to use that phenomenon to your advantage. If the height of your dummy tiers are shorter, the cake will read as being larger when you photograph it close up. A tier that's 6" across and 4" tall will look the same as a tier that's 3" across and 2" tall if there's nothing in the photos to act as a size reference.
These cakes are the ones that I used in the video:
They look very similar in size, but watch the video to see how big they really are in comparison to each other. The white one is about 3" shorter than the pink one, and is also narrower. You can't tell that in a picture that frames the cake, though.
I could make teeny tiny display cakes that are 6" tall as long as the decorations on them are also teeny tiny. It would solve a lot of storage problems, but you'd have to be able to work in miniature. These also wouldn't necessarily be good to take to wedding shows, but they're good for photos for a portfolio!
Kara Buntin owns A Cake To Remember LLC, custom wedding cakes in Richmond VA and online cake supplies at www.acaketoremember.biz and www.acaketoremember.etsy.com