How to reduce Noise in Images using Photoshop
Image noise can be caused by using cheap equipment to take photographs. Image noise can be caused by using high ISO while taking photographs in low light. ISO refers to the camera’s sensitivity to light. The higher the ISO the brighter the photo will appear. The image may have noise because the camera may have a slow shutter speed. Noise can be caused by underexposure. Noise can also be caused by a scanning sensor. Noise can be even more obvious when the image is sharpened, that is why it is best to reduce the noise before enhancing the image. While some noise is good in an image, having too much noise can make the image have poor quality. Once the image has noise, it cannot be removed without damaging the image, however, you can reduce image noise with Photoshop.
1] Types of Noise
There are two types of noise that an image may have, Color Noise and Luminance Noise. Color noise appears as spots of red, green, and blue color where they are not supposed to be. Luminance (grayscale) noise, makes an image look grainy or patchy. Luminance noise affects the brightness of pixels, but it doesn’t harm their original colors. There is one more thing that can affect your image that Photoshop can help to correct, and that is JPEG Artifacts. JPEG Artifacts are blocky distortions or halos in the image caused by saving with a low JPEG quality setting. JPEG is a compression format, so it compresses your image when you use it. Each time you save a JPEG image it loses some of its quality. Your device may save your file as a JPEG, or you created the JPEG when you saved the file. Since JPEG is a smaller file, it is used in most cases to save images, however JPEG damages and degrades the file.
2] Preparing the Image
To begin processing the image, open it in Photoshop. Open Photoshop then go to File then Open then find the image, then select it and click Open. Zoom in and out of the image and observe it. See if you can observe any of the noises mentioned above or the JPEG Artifact. Note if you are planning to increase the resolution of the image or if you are planning to enlarge the image, reduce the noise first. Noise can be made more obvious when the resolution or size of an image is increased.
This is the original image. Zoom in and out and observe. You don’t have to zoom in a lot to start seeing distortions in the image.
I observed some JPEG Artifacts especially around the edges, closer to the skin. can you see the boxy colors?
3] Reduce Noise – Basic Mode
To begin working on the image you need to duplicate the image and make changes to the duplicate so that the original is protected.
To duplicate the image, go to the Layers panel and right-click on the image then press Duplicate Layer. You can also duplicate the layer by clicking on the image and dragging it down to the Create a new layer icon at the bottom of the Layers panel. A new layer will be created, it will be a copy of the first layer so it will be named xx copy it will be above the previous layer. Another way to duplicate the layer is to press Ctrl + J.
To begin using the filter, convert the top layer to a smart object by right-clicking on it and choosing “Convert to Smart Object”. Converting to a smart object will allow the noise reduction adjustment to apply as a smart filter. This way you can easily edit it later if you need to.
With the copy layer selected go to Filter then Noise then Reduce Noise. The Reduce Noise filter dialogue box will come up for you to make adjustments. Stay in the basic mode, which is the first mode that the Reduce Filter will be on. Note there will be no hard and fast rule in the value that will be needed for each. This means you will need to move the sliders slowly and observe the changes to your image. The image used in this article will have a different level of noise and JPEG artifact present in it. Here are the different parts of the Reduce Noise filter dialogue box and what they are for: There is the Ok and the Cancel button so that you can confirm or cancel changes.
There is the Preview check box for you to check or uncheck if need or do not need a preview of the changes on the original image as you work. There are the options of Basic and Advance. The basic is the first set of controls that you see and the advance offers the option to change the Luminance on each channel (Red, Green, and blue) separately. The reduce noise dialogue box has a preview window so that you can see what is happening as you make changes. There is the Settings drop-down menu, you can save settings after you have made them and they will appear in the Settings drop-down menu. Just press the little box with the arrow, and a New Filter Setting dialogue will appear for you to name your new setting. The Strength and Preserve Details are used to remove Luminance noise. The Reduce Color Noise is used to reduce color noise in the image. Under the preview window you will see – and + buttons, you use these to zoom in and zoom out on the image that is previewed. While still in the Reduce Filter dialogue, zoom the previewed image to 100% so that you can see the noise. The Reduce Noise filter will be in the Basic Mode. These are the controls that are available in the Basic Mode. Go to each of the sliders and adjusts them and watch the changes in the image. Strength – This is used to reduce the Luminance noise in the image. Click in the Strength value box and use the Up or Down arrow on the keyboard and adjust the values, watch as the image changes. Stop changing the values when the image is satisfactory. Preserve Details – The Preserve Details slider is used to bring back as many of the details of the image. The Strength slider would have removed some of the image’s original details so the Preserve details would help to bring back as many of the details as possible. Remember that it will not be possible to get a perfect image, however, try to make the image as realistic as possible. Reduce Color Noise – This Slider removes color noise in the image. Use this slider if you notice color noise in your image. Sharpen – Keep this slider low as sharpening the image may show up the noise again. Place it at zero then click in the value box and use the Up arrow on the keyboard to slowly adjust the value. Observe the image and stop adjusting it when it looks satisfactory. Remove JPEG Artifacts – You may notice in your image that there are JPEG Artifacts. JPEG Artifacts are blocky distortions or halos in the image caused by saving with a low JPEG quality setting. Check the Remove JPEG Artifact option and see the blotches disappear. When you are finished editing, click Ok to go back to the canvas.
4] Reduce Noise – Advanced Mode
To begin working on the image you need to duplicate the image and make changes to the duplicate so that the original is protected.
To duplicate the image, go to the Layers panel and right-click on the image then press Duplicate Layer. You can also duplicate the layer by clicking on the image and dragging it down to the Create a new layer icon at the bottom of the Layers panel. A new layer will be created, it will be a copy of the first layer so it will be xx copy it will be above the previous layer. Another way to duplicate the layer is to press Ctrl + J.
To begin using the filter, convert the top layer to a smart object by right-clicking on it and choosing “Convert to Smart Object”. Converting to a smart object will allow the noise reduction adjustment to apply as a smart filter. This way you can easily edit it later if you need to.
With the copy layer selected go to Filter then Noise then Reduce Noise. The Reduce Noise filter dialogue box will come up for you to make adjustments.
For this method, go over to the Advanced mode instead of staying on the Basic mode.
The advanced mode allows you to isolate each channel (red, green, and blue) and remove noise. You can scan the picture to see which channel has more noise and remove it. Oftentimes one channel will have more noise than the others. Below the channel button, there are two sliders, Strength and Preserve Details. The Strength option allows you to remove noise, and the Preserve Details allows you to bring back the details that were lost during the noise removal process. The best way to control both Strength and Preserve Details is to place both at 0 value, click inside the value window, and use the keyboard’s up and down arrow to change the values. Move slowly and watch the changes in the images. Remember that you will have to observe the changes in the image and stop when the image looks satisfactory. When you are finished processing press OK to confirm and keep changes made to the image.
This is the image after the process of Noise Reduction has been completed and has been saved.
5] Save
After all that hard work making that image look more pleasing to the eye, it would be very counter-productive to not save that image properly. The first thing to do is to save the finished image as a Photoshop PSD so that you preserve the editing capabilities and the quality. Save the image as TIFF or PNG so that more of the details are stored. Saving as a PGN also have the added benefit of saving without the background. Remember that saving as JPEG will compress it and some quality will be lost. However for storage and web use, you may have to save it as a JPEG, just be sure to use the highest JPEG setting to save the Image. Note that saving as a JPEG should be left to the final save because each time a JPEG is saved it degrades more and more.
To save go to File then Save As, the Save As dialogue box will appear, fill in the File Name name and choose the file Format and click Save. Read: How to improve Image Quality in Photoshop CS6
How do I reduce raw noise in Photoshop?
Open an image in Camera Raw that has a digital noise issue, press Z to get the Zoom tool, and zoom in to at least 100%–200%, so the noise is easily visible. To decrease color noise, drag the Noise Reduction Color slider to the right. Take note of the changes and stop when the image looks satisfactory.
How do you remove noise from a picture in Photoshop?
Click on Filter, hover over Noise, and click Reduce Noise. Set the value of Strength to 0% to start. Drag the Strength slider to the right to remove as much of the luminance noise as possible. Avoid dragging the slider too far to the right to remove the details from the photo. Do the same process for Color Noise, move the slider to the right. Observe changes in the image and stop when it looks satisfactory. Noise cannot truly be removed without actually removing important details from the image, you can only reduce the noise.
How can I capture photos with no noise?
Shoot in Raw.Get the correct exposure.Keep the ISO under control.Be careful when taking long exposures.Use large apertures.Turn on your camera noise reduction.Take advantage of your camera’s high ISO noise reduction (if you shoot in Jpeg).Use cameras with full-frame sensors.
Why are my photos so noisy?
The graininess you’re referring to is called noise, and it’s caused by having your ISO set too high. While it seems nice that your camera offers you a high ISO, it doesn’t mean it can be used at the highest setting and produce a quality image. ISO refers to the camera’s sensitivity to light. The Higher the ISO number, the more sensitive. This comes with a drawback because the more sensitive the more chance for there to be noise. Your photos can be noisy when you turn the ISO high and shoot in low light. Photos can also be noisy when you use cheap equipment to take photos. Using the correct equipment and proper lighting can greatly reduce noise in your photos. However. If all that is not available, Photoshop can help to reduce noise in your photos.
