Layered PDF- an alternative wanted

[#1]

I've use a couple of software packages that allow me to create a layered image as a PDF.
The layers as an example could be a Map showing historic Aerial Photographs  showing land use for 1960, 1980 and 2000, overlayed with layers for footpaths, field boundaries, river, buildings, roads, labels whatever.
Or it could show the results of a photopoint survey taken from a fix point once a month for two years to show change.
Simple example attached, I use adobe 9 and Fox 5
You open the PDF, click on the layer Icon, by checking/unchecking  the tick box for the various layer, they are made visible or not.
The question this leads to:- Does anybody know any other format (other than PDF) that will let the user produce layered image output.
(edit:- non copyright layered pdf added)

[#2]

There are several other formats (primarily image types) that support layers,  but the're more aimed at the production side.
PDF is the only consumer format I'm aware of that's open(ish).

[#3]

Quote from: journeys

The question this leads to:- Does anybody know any other format (other than PDF) that will let the user produce layered image output.

No - but you can do the same thing using AutoCAD.