Noise in your photographs
We all have to make photographs in darker conditions than we might like. This means pushing your ISO higher and incurring the dreaded ‘noise’ in your photographs. It’s something I get asked about a lot during my photography lessons as people tend to worry a lot about this. Below are examples of noise being generated in an image by increasing the ISO on the camera. Click to see a larger version.
We are conditioned by the media to expect that every photo must be completely clean and bright; perfectly in focus without any noise to be seen. Invariably what we are presented with are studio or set-up shots which have had perfect lighting and then Photoshop work done on them in post production.
However, many of the photojournalistic images we’ll see inherently have noise in them, it’s just we don’t notice. The reason for this? The content is interesting, arresting even, meaning we aren’t thinking about the technicalities of the shot. The image below is the 2016 winner of the World Press Photo Contest. Taken with high ISO at night, the noise is clearly visible. Does it take away from the subject matter or actually enhance it?
Noise has the effect of making the image lose detail meaning what you saw with your eye as crisp focus becomes a much softer, sometimes ‘muddier’ version of what you saw. This comes back to my first point, expectation levels.
Different cameras, different noise
All manufacturers now produce cameras with high ISO ability, some extraordinarily so. It is the feature that, latterly, all manufacturers fight over to try and bring in their new and existing customers. Indeed, it is one of the main advantages digital photography has over film photography. Instead of needing to frantically change to a faster film, slow the shutter speed to a ridiculously slow rate or use the fastest lens we have, we now just change the sensitivity to compensate for the lack of light.
Not all noise is created equal and this is where I think the problems start for photographers with lower end and older cameras (the technology for noise reduction has come along in leaps and bounds over the last few years). The sensor that reads the light is also responsible for that pesky noise. The lower the light and higher the ISO the more sensitive it becomes, not just to the light but the environment in general. Other factors, such as heat, interfere with the sensor as it picks up more information than it needs to produce the clean image.
In general, the more expensive and newer the camera body, the less noise you would expect to see. Older models tend to have older technology for noise reduction and this is where I see the disappointment coming in from people with cameras that are only a few years old.
Unlike film photography grain which is random, digital photographs tend to produce a regular noise which in itself can be distracting to the eye. You can practically pin-point a camera manufacturer by the ‘style’ of noise that is produced by the camera, it’s almost a sensor’s fingerprint. Adobe have combated this by including an effect in Lightroom whereby you can actually add random noise back in to your photo.
I would have to say though that if you, as the viewer, are being distracted by the noise in a photo, it’s possible the content of the photo isn’t quite grabbing your attention as it should (see above).
How do I stop the noise?
Buy a new camera. As I mention above, newer camera sensors tend to deal with noise quite a lot better than those only a few years old. That’s quite a drastic not to mention expensive step to take if you are just a casual photographer though.
Use a faster lens. Lenses which have a wide aperture (f1.2, f1.4 for example) allow more light to hit the sensor when at their max. This means you won’t need to raise your ISO as much as with your kit lens which would normally be something like an f3.5-5.6. A 50mm lens is normally favourite and the f1.8 is great value for money no matter what camera you use. Of course you can get wider apertures but the expense starts to rise!
Shoot with lower shutter speeds. If you are used to shooting at high speeds in bright light you may need to bring your shutter speed down (in turn bringing your ISO down). Practice bracing yourself against walls, railings, anything that will give you a steadier camera to avoid the camera shake. You’ll be surprised how slow a shutter speed you can use and still get a great shot.
Learn to use Lightroom or a similar package to reduce the noise in post production. It’s a delicate balance between softening the pixels and contrast (meaning losing definition) and getting to a point where you are happy with the noise levels. Be sure to shoot in RAW so you have control of the noise in Lightroom.
Learn to love the noise. Having noisy photos isn’t the end of the world. Take a series of photographs, each one with the ISO increasing and see where your threshold is for noise. As with anything, it tends to be a personal preference.
Choose your moments. Noise tends to show up in block colours. It is much harder for us to see in ‘busy’ images such as market places, carnivals or anywhere where there is plenty going on in the frame for our eye to be distracted by.
At the end of the day it is down to you how much noise you can handle in your shots. But one thing is for sure, without the confidence to push your ISO higher you could be missing out on some amazing photographs!