There has been a long gap between posts (again!), and a lot of the stuff that I’m going to talk about in this post is fairly old too. Oh well, life keeps getting in the way of blogging. Anyway, I’ve recently submitted a talk for the FOSS4G UK 2026 conference in Leeds in October, and […]
A friend was using GDAL’s ogr2ogr command to import some data to PostGIS recently, and as part of the import they were doing a reprojection of the data. They got the following error: PROJ: Cannot open https://cdn.proj.org/uk_os_OSTN15_NTv2_OSGBtoETRS.tif: schannel: the certificate or certificate chain is based on an untrusted root They’ve had various SSL errors on […]
I’ve got into a bit of a habit of writing occasional posts with links to interesting things I’ve found (probably because it’s a relatively easy blog post to write). This is another of those posts – this time, written in June 2025. So, let’s get on with some links: Why COUNT(*) can be slow in […]
Summary: I’m involved in organising a hackathon, and I’d love you to take part. The open-source GeoTAM hackathon focuses on estimating turnover for individual business locations in the UK, from a variety of open datasets. Please checkout the hackathon page and sign up. There are prizes of up to £2,000! (Click image for a larger […]
A quick post today to talk about a couple of PostGIS functions I learnt recently. I had a CSV file that contained well-known binary (WKB) representations of geometries, stored as hexadecimal strings. I imported the CSV into a PostGIS database, and wanted to convert these to be proper PostGIS geometries. I initially went for the […]
It’s been a while since I posted here – I kind of lost momentum over the summer (which is a busy time with a school-aged child) and never really picked it up again. Anyway, I wanted to write a quick post to tell people that I won two awards at the British Cartographic Society awards […]
For months now I’ve been collecting a load of links saying that I’ll get round to blogging them "soon". Well, I’m currently babysitting for a friend’s daughter (who is sleeping peacefully upstairs), so I’ve finally found time to write them up. So, here are a load of links – a lot of them are geospatial- […]
I was recently trying to set up RasterVision on my Apple Silicon Mac (specifically a M1 MacBook Pro, but I’m pretty sure this applies to any Apple Silicon Mac). It all went fine until it came time to install the triangle package, when I got an error. The error output is fairly long, but the […]
For a while I’d wished there was an easy way to get notified when my favourite open-source packages release a new version. I’d often see something on social media, but that tended to only be for the larger packages – and I wanted to keep up with the smaller ones too. When I actually bothered […]
Summary: You can use QGIS expressions to set the default path for an Attribute Form to be something like @project_folder || '/' || 'MapGraphs', which gives you a default path that is relative to the project folder but also has other custom subfolders in it. I spent a while redrafting the title of this post […]