This is what three historic aerial photos covering the area from Water of Leith to Andersons Bay Road look like. After a long complex process of sizing and rotating I have these all lined up ready for the masks to be done on the 2013 Linz aerial imagery. The masking is complex because rail tracks used to cover a lot of area in this part of Dunedin, as they went around various industrial areas and across wharves. I am trying to mask out as little as possible of the current day imagery which means a lot of work selecting just the areas that have rail tracks in them, and so far I have only done a little.
At the same time it looks like I am possibly converting all my Qgis projects back to version 2.18 as I have all but decided to ditch the development masters. At this stage I am not sure what work is needed, but the project files for 2.99 are only partly readable in 2.18 so some areas of layer styling are going to have to be hand ported per project. I have just finished setting up the testpc with Debian 9.3 and Qgis 2.99 and put 2.18 on mainpc to start the work of backporting projects with.