How to get better autofocus
June 23, 2021
Mirrorless cameras have introduced a range of new autofocus systems, so Angela Nicholson explains the good, the average and the downright amazing
As mirrorless cameras don’t have a mirror to bounce light into a viewfinder or onto a dedicated autofocus sensor, they use the imaging sensor to gather the focusing information to drive the lens. The first mirrorless cameras used contrast detection autofocusing, and although some manufacturers have stuck with it, most use phase detection or a hybrid system that combines phase and contrast detection.
Contrast detection is a very accurate method that looks at the edges of the subject and moves the focus until the point of highest contrast is found. Its problem is that the camera has no way of knowing which direction to adjust the focus initially, so it can go the wrong way.
Which camera maker has the best autofocus for moving subjects?
May 22, 2021
Autofocus systems have become very sophisticated over the last few years. In the third of our Nobody Does It Better series, Angela Nicholson looks at which camera manufacturer makes it easiest to get moving subjects sharp.
Let’s start with a bit of background… Most of the light that exits the lens on a single lens reflex (SLR) camera is reflected up by the mirror into the viewfinder but a small amount passes through and onto a secondary mirror which reflects it towards the dedicated autofocus sensor.
A small lens assembly splits the light so that it forms two images on the line or cross type sensors on the autofocus (AF) sensor. If the two images align, the lens is focused on the subject, but if their alignment is not correct and the images are out of phase, the camera knows which direction to move the lens focusing group and by how much. This process is known as phase detection focusing.
Which camera maker is best for connecting to smartphones?
May 10, 2021
For the second in our new series, Nobody Does It Better, Angela Nicholson looks at which camera maker offers the smoothest tech for transferring your images, updating camera firmware and more
All the camera manufacturers give their cameras Wi-Fi and Bluetooth connectivity to enable them to connect to smartphones running their app, and some have systems that are supposed to enable images to transfer automatically to your phone rather than having to select them individually.
However, Nikon’s SnapBridge is the only smartphone connection system that I’ve ever been able to get to transfer images consistently.
April 8, 2021
One of the great things about digital photography is that, unlike film, you’re no longer tied to a single sensitivity (ISO) setting for a batch of 24 or 36 shots. It means if you set out in sunshine, but then head indoors, you don’t have to muddle through with the same ‘film speed’, or reach for a tripod, you can adjust the camera’s ISO setting accordingly.
Before noise reduction is applied…
…and after
However, many photographers get very anxious about moving up from the lowest sensitivity settings because they’re worried that the image quality is going to take a nose-dive. Read on to discover how you can assess your cameras high-ISO performance, decide your safe maximum ISO and get more from the results.