Removing "Noise" with Lightroom

One of the biggest advantages of digital cameras or DSLR’s over their film counterparts is the ability to switch ISO settings on the fly. ISO is the amount of light that you let into the camera’s sensor and in the days of film cameras this was accomplished with film speed, sometimes called ASA instead of ISO.

So if you wanted to shoot outdoors, you would load a roll of ISO or ASA 100 or 200 and be good to go, but if you then moved into a dimly lit building and wanted to shoot, you needed either a flash on that camera or you needed to have used up that roll of 100 or 200 film and switch to 400 or 800 to shoot well in those conditions.

With the advent of the digital camera, you can shoot outdoors at ISO 100, and then step indoors and with the flip of a switch or wheel, shoot at ISO 800 or even higher like 6400 or maybe even 12,800. The problem is as your ISO gets higher, you get digital “noise” in your photos. Noise is the little dots, speckles or grain look in your image that I am sure most everyone has seen at one time or another.

See the grains of noise in this image. I shot indoors at ISO 2000

 Some cameras are better at others at handling high ISO, low noise, but at some point even the best of these cameras will end up with noise in your images and it can make the image ugly and unusable. Luckily, Lightroom can help mitigate this for you and make this image useable again.

When you load your images in Lightroom and come across an image that has noise, this is how you can clean it up in the Lightroom Develop Module. The two big noise removal sliders are under the Detail section and called Luminance and Color.

After some Luminance and Color noise reduction notice the image is much cleaner

Here is what each does. Luminance: This kind of noise affects the brightness, but not the color, of individual pixels. If you had a picture of a dark grey piece of paper with a great deal of luminance noise it would appear similar to old-school television static with lots of light and dark fuzz.

Color or sometimes called Chroma noise: This shows up as oddly-colored pixels, scattered throughout an image, almost like someone has tossed a handful of red, blue, and green grains of sand at it. Lightroom calls this “Color” noise, but it’s just another term for Chroma noise.
Now, although you can remove considerable noise with Lightroom, you want to make sure you are careful not to use too much noise reduction as it can make the images look fake and give everything a plastic look. A lot of pros will counter some of the effects of the noise reduction by using some sharpening as well for the best results.

A side by side of the before on the left and after on the right.

 As you can see in my side by side before and after shot, the Lightroom noise reduction did help clean up this image a lot.

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Keep Down the Noise!

This week I thought I’d write about another subject that I am frequently asked about, noise. First let’s take a look at noise as it pertains to photography. What is noise? Well, noise is the pixelation that happens in your images when you use too much ISO.

Many of the new cameras are capable of high ISO settings, some as high as 256,000 believe it or not. Increasing the ISO on your camera allows you to compensate for low light conditions but is not the ideal way to compensate for it. The ISO setting makes your cameras sensor more sensitive to lighting and your exposure. As you move the number higher, you camera is able to pull in more light from the available light in the conditions. The bad part is when you go too high in ISO, you start getting noise introduced into your images and they start to look sloppy instead of having a nice, fine quality.

Even though most modern cameras can go to large ISO settings, it’s not recommended to do so as the quality of your image will suffer. If you ask most any professional photographer, they will tell you that the maximum ISO that anyone should ever use is ISO 800, as once you get above ISO 800, noise really becomes an issue. Ideally, they will go on to tell you that ISO 50 or 100 is the best to use as it offers the finest quality to the final image. So, how do you keep down the noise if you are shooting in less than ideal lighting conditions? By using a better lens, capable of a wider aperture to allow more light to reach your sensor or by using artificial lighting, such as strobes or continuous, hot light kits.

This image shot at ISO 3200, notice all the noise?

The wide lens option is the best as a lens with a wider aperture will naturally allow more light in. Thins of the aperture of your lens as being the same as the pupil in your eye. When you are in low light conditions, your pupils enlarge so that your eyes can take in more light and allow you to see better. If it’s a bright, sunny day your pupils will become very small as you don’t need as much light allowed in to see. Aperture works the same way as your pupil, when you have a wide aperture lens, say an F/1.4 your lens is opened up allowing more ambient light into your sensor to make the exposure. The down side of wide aperture lenses is that they are generally expensive. Take the most popular lens from one of my earlier posts, the 70-200mm. As I mentioned in that earlier post the 70-200mm from Canon comes in two apertures, F/4 and F/2.8. The F/4, which I currently own is a fantastic lens and takes beautiful images with outdoor light, but if I needed to shoot indoors, say at a concert or indoor sports like basketball the F/2.8 will work better because it can open wider than the F/4 and let more of the natural light in that environment into my sensor. The difference in price is significant, with the 70-200mm F/4 L lens costing around $800 and the 70-200mm F/2.8 costing around $2,100.

Same image shot at ISO 100, notice the fine quality?

As I mentioned earlier in this post, the other option to prevent noise is to use artificial lighting such as a Speedlite external flash, or full blown strobes or even hot lights. These will allow you to keep your cameras ISO down really low if the lights are powerful enough to compensate for the poor natural lighting. Flash is not ideal in most low light conditions such as concerts or indoor sports as the flash is distracting, which is why if you are at a basketball game or watching one on TV you will notice that most all of the sports photographers there will have no flash but will instead be using that big fat F/2.8 70-200mm to get the shots they need for sports magazines and websites.

Now, since most of the AI family reading this post are students, I am assuming you are not rich enough to buy all your lenses at F/2.8 or wider as it is very costly. I would recommend to you that you invest in one expensive F/2.8 zoom such as the 70-200mm and buy the rest of your lenses in whatever aperture you can afford and use. If you do want to buy a good 70-200mm F/2.8, then you can always rent one from www.borrowlenses.com or from www.lumoid.com. I personally love Lumoid as they let you try before you buy and if you want to own that lens, they will split that cost up over three months to make it more affordable. I am not certain Borrow Lenses offers the same option as I have never used them but I know Reuben has and he can probably best answer that question.

Now get out there and make some great images.

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