Hi Garry,
Firstly I’m going to do an Inspiration Sheet on the whole topic of HDR – but it may be a few weeks before it is out. So let me give you a little bit of the basics – you are right when you say that true HDR requires multiple exposures and then they need to be combined together in post-production. However it is possible to create similar effects in other ways, but they are not really HDR in the truest sense.
If you want to create pseudo-HDR you really need to be working with RAW images as they give you a bigger dynamic range to start with, and you need to make sure that you don’t overexpose the highlights, because once you have lost highlight detail it has gone forever. When you bring back detail in the shadows it does cause noise in the image, and that’s the main downside of doing a pseudo-HDR. Some of my images have an HDR look to them that has been achieved by using Nik Efex plugins (a lightroom/photoshop plug-in – https://nikcollection.dxo.com/) or using SnapSeed on the iPad/iPhone (also available for Android).
