When it comes to noise reduction, you always have two goals. First, obviously, you want to get rid of any digital noise in your picture. But secondly, you want to preserve detail. These often work against each other because increasing noise reduction often leads to a loss of image detail, but if you focus on preserving the detail then you may end up with a noisy picture.
So what can you do about it? Different people have different methods, but for me, there is a good, better, and best way to go about noise reduction. As you might imagine, my good way is simple, the better way involves a little more effort, and my best way requires a lot more effort (and can be rather complicated). In this article, I will walk through my favorite options so that you can decide if one of them is appropriate for your own noise reduction workflow.
“Good” Noise Reduction
Lightroom has very good noise reduction tools. They are powerful and really easy to use. They reduce noise and do a decent job of preserving detail. Further, the noise reduction in Lightroom seems to get a little better with each new iteration. If you want a good noise reduction tool that will take up almost none of your time, simply use Lightroom.
The primary slider is the top one labeled Luminance. I think of that as the amount of noise reduction being adding to your photo. From there, you can fine-tune your noise reduction using the additional sliders below it. Frankly, however, if I am using Lightroom for noise reduction, it is because I want it to be quick and easy, so I usually just use the Luminance slider.
Suggested starting points
You may be wondering about a starting point for the amount of noise reduction to apply. Of course, that is hard to do, and it depends on a lot of things. First of all, it depends on the ISO value you used. It also depends on the low-light performance of your camera. However, I hate the “it depends” answer, so to give you an idea of a starting point taking into account those variables, here is a chart with some suggested values for the Luminance slider.
Of course, there are other factors involved as well, which this chart does not take into consideration. For example, dark tones will show noise much more than lighter tones, so you may need to increase the amount where you have darker tones. Just use this chart as a starting point, and don’t take it as a definitive range that you must stay within. Always do whatever the picture requires, even if it is drastically different than what is set forth here.
Read more on noise reduction in Lightroom here: How to do Noise Reduction in Lightroom
Selective Adjustments in Lightroom
The noise reduction settings within Lightroom will apply to your entire picture. We are going to get into selective noise reduction later, but I should mention here that you can also use the Adjustment Brush in Lightroom to selectively add noise reduction.
Select the Adjustment Brush and find the slider labeled Noise. That’s right – you only have one slider for this, so think of it as the equivalent of the Luminance slider you used above. From there, just set your brush size (you can use your left and right bracket keys for this) and paint in the effect where you want it. You’ll see better ways to selectively apply noise reduction in a minute, but if you aren’t too picky about the selection then the Adjustment Brush might be the tool for you.
“Better” Noise Reduction
Normally, when I want to bring out the heavy artillery in any aspect of post processing, I find that I need to head into Photoshop. That is sort of true here, in that we will be heading to Photoshop, but then again not true in that we won’t be using Photoshop’s noise reduction. I find that Photoshop’s noise reduction tools aren’t that great, and Lightroom actually works better (there are plenty of people that disagree with me though, so make up your own mind about that as you use them both).
Instead, I merely use Photoshop to take advantage of third party noise reduction software that works within Photoshop. Yes, you could also use them from Lightroom, but using them within Photoshop will allow you to take advantage of Photoshop’s powerful masking techniques (which you will see in a minute).
Noise reduction plugins
What are these noise reduction applications that are available? Let’s take a look.
- Noiseware: First, we have Noiseware by Imaginomic. I mention this first because it is the application I have used for my own noise reduction for the past several years. It works really well, does a great job eliminating noise, is simple to use, and it preserves a lot of detail. There are several presets to choose from and then a few sliders to make adjustments from there.
- Nik Define: A free option is Nik Define. It is part of the Google Nik Collection, which is now free. It does a nice job of reducing noise, and if you are looking for a free option this is a good one. The downside is that it appears this software is no longer being updated and its days are numbered.
- Noise Ninja: This is part of the Photo Ninja Suite by Picture Code. The entire suite costs $129. I personally have not used it, but the reports I have heard from others and the reviews have always been positive. Read: How to Reduce Noise with Photo Ninja for more info.
- Topaz Denoise: Topaz makes a series of plug-ins that do a variety of functions really well. Their noise reduction software is called Denoise and it costs $79 (or you can get the whole suite of apps for $500). I haven’t used this one either, but the reviews have been good and my experience with other Topaz apps has been very good.
- Macphun’s Noiseless: Inside Macphun’s Creative Kit you will find the Noiseless plugin (you can also buy it alone). Read this for more info on this option: Macphun Noiseless Pro Software Review
Any of these will do a nice job.
“Best” Noise Reduction
The best way I have found to apply noise reduction is exactly the same as the way you just saw, except that you apply it selectively. The reason is that noise reduction reduces detail in your image. It is often hard for noise reduction software to tell the difference between noise and important detail. That is particularly true in night sky photos, where the many stars can resemble the random flecks that constitute noise.
Basic Masking
To avoid having your noise reduction software reduce detail, you can use Photoshop to mask off the more important areas of the sky. To accomplish that, you just create a layer mask so that the noise reduction only applies to certain parts – which will be white in the mask – of your image.
A simple, but admittedly imprecise, way to do this is with a brush. If you start with a “reveal all” (white) layer mask, you will then use the brush (color set to black), which will keep the noise reduction from reducing detail in the areas you choose. On the other hand, if you start with a “hide all” (black) layer mask, you will paint the entire mask with white except the part where you want to preserve detail. You can get as course or fine as you want (or time allows).
How to do you do it? First create a new layer copy (Ctrl/Cmd+J if your picture only has one layer, or Ctrl/Cmd+Shift+Alt+E if you have multiple layers already), then apply your noise reduction as you normally would. After that, just click on the Add Layer Mask icon at the bottom, which will create a white (reveal all) layer mask (or press Alt while doing so to create a black layer mask to hide all). Then just use your Brush (B) to paint with the opposite color as your mask.
You can get as involved as you want with masking. You likely have your own favorite ways already, so go ahead and use them. There is no right or wrong way to mask.
Applying Noise Reduction
So those are my three ways to apply noise reduction. You can add some quick noise reduction in Lightroom, which takes only a second. For slightly more involved but also more powerful noise reduction, add the addition application of your choice. For your most important pictures – or the ones with the biggest problems – add noise reduction and then use masking to limit the effect to the specific areas you want.
These are just my ways though. Do you have your own special methods that are different? If so, let us know about it in the comments below.
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