HQ CAMERA
Take better photos with your Raspberry Pi
Mike Bedford explains how to get the most from the Raspberry Pi HQ Camera and learn the basic principles of photography at the same time.
OUR EXPERT
Mike Bedford has embraced all that digital photo techniques bring, but does like to play with manual controls, so the HQ Camera is surely a winner.
W hen Raspberry Pi launched its HQ Camera in 2020 (see reviews LXF264), it introduced something very different from their previous two cameras. While the other two camera modules are made up of a sensor and its interfacing electronics together with a lens, the HQ Camera doesn’t have an integral lens. This means that you need to buy one or more lenses separately, and Raspberry Pi offers a couple of alternatives that we look at here. In that way, it’s similar to digital SLRs (D-SLRs) cameras, but different from the cameras in phones or compact standalone cameras.
Our aim here is to introduce the HQ Camera for those who haven’t yet taken the plunge, and to follow this up by investigating how to use some of its lessfamiliar features, and at how to choose lenses as alternatives to those provided by Raspberry Pi. Armed with this information, we trust that many of you will decide to try your hand with the HQ Camera, and that it will form the basis of some fascinating new projects. Indeed, we already have some plans to present some exciting things you can do with it in the coming months.
The new sensor has a higher resolution – specifically 12MP, which compares to 5MP for the original camera module and 8MP for the v2. But although that megapixel figure is the one that most users concentrate on, the size of the sensor is also significant because the larger the sensor, the more light it gathers, and this also improves the image quality. So we should point out that while the original and v2 camera modules both had 1/4- inch sensors, the HQ Camera has a 1/2.3-inch sensor. These figures don’t relate directly to the sensors’ width, height or diagonal, but the area of the sensor in the HQ Camera is about three times greater than that of the earlier RPi cameras. For reference, consumer D-SLRs have sensor that has a 12-times larger area again, and that increases by a factor of another 2.3 in professional full-frame D-SLRs.
The HQ Camera supports lenses with C or CS mounts, which are standards commonly used in CCTV cameras. While these are widely available – although not always affordable – Raspberry Pi has picked a couple of third-party lenses that are the “official” offerings. One has a focal length of 6mm and the other 16mm – see the boxout (left) for more details.
FOCAL LENGTH EXPLAINED
The focal length is proportional to the magnification provided by the lens and is inversely proportional to its field of view. However, direct comparisons can’t be made between different lenses if they’re used in conjunction with differently sized sensors. For that reason, a 35mm equivalent focal length is commonly quoted because it’s familiar to photographers and provides an easy way of making comparisons.