Freeware Noise Reduction Software - 03 Sep 2009

A few weeks ago I received an e-mail from Glenn Chan, author of Free Photoshop Plugins website, offering me to download his "free" Colormancer's Freeware Boundary Noise Reduction Plugin for Photoshop (CS and Elements). Glenn suggested I evaluate it as a free post-processing tool for digiscopers and photographers. So I decided to download it and try it out. The following is my review of the software, and my recommendation for all you digiscopers looking for economic post-processing options for improving your images, both for printing and web presentation.

First thing to note is that the software is Free! Well, mostly... The 'Basic' version of Boundary Noise Reduction Ver. 1.4.0 is Free. The 'Advanced/Commercial' version is not. But that's ok, since I found that the Freeware version works just great. What this software touts is the ability to concentrate noise reduction to outer edges and border features, leading to more 'natural' transitions and smoother edges with less artifacts. I had to agree.

The software downloads as a Plug-in for Photoshop CS (or greater), Elements 2.0 (or greater), PaintShop Pro X2, IrfanView, and GIMP. Don't be alarmed if you're not familiar with plug-ins - the download gives you 2 files that are simply moved into the Plug-Ins folder of your software (\Program Files\Adobe\Photoshop CS\Plug-Ins) and automatically loads the software when you open the program. In the case of Photoshop CS the noise reduction program can be found under \Filter\Colormancer. And its simple to use! The only slider you really need to adjust is the 'Overall Noise Level' (highlighted green at left).

I digiscoped this Ruby-throated Hummingbird last week using the Nikon Coolpix P6000 and Zeiss 85T*Fl. At ISO 100 the image produced very little-but noticeable-noise. You can see at left how adjusting the Overall Noise Level slider from 0 - 300% affects image quality. At 25-50% the image cleans up nicely w/ little loss of detail. Going to higher noise reduction levels will, however, begin to smear detail and produce a watercolor effect that may or may not give you the desired output you're looking for.

Should you decide to purchase the 'Commercial' version, you'll have access to more detailed adjustments. I played w/ these a bit but found nothing that I needed for my imaging workflow. These adjustments are available w/ the Freeware version, but will produce a watermark on your image should you decide to apply the Advanced settings. Boundary Noise Reduction Plug-in for Photoshop does a wonderful job at removing Luminance Noise. I normally like to highlight my subject (bird), apply minor noise reduction, then select the background (inverse) and apply more aggressive noise reduction to give images that film-like quality. Unfortunately for me, the software does not allow 'selective noise reduction'. But, if I highlight my subject, make a copy of it, then paste it back into the image as a new layer, I can apply separate noise reduction to each layer. When I'm finished, I can flatten the image and end up with the same result.

How does it compare w/ my current noise reduction software? I use Imagenomics Noiseware Professional. I reviewed this software earlier, and chose it over Noise Ninja and Neat Image (both terrific packages). I photographed this Willow Flycatcher a few weeks ago using my Nikon D300 and Sigma 400mm f/5.6 at ISO 400. I was curious to see how the Freeware software treated the background Luminance noise.

As you can see, Boundary Noise Reduction Plug-in worked extremely well! It even left slightly fewer edge artifacts than Noiseware when viewed at 300% magnification (at lower mags these artifacts were invisible).

Chroma noise is a bit more troublesome. When blown up to 400% this image of a Wilson's Phalarope, taken w/ an old Coolpix 990, showed significant chroma noise in the eyeline feathers around the eye and crown. Noiseware removed the noise cleanly while preserving feather detail w/o loss of detail. Boundary Noise Reduction Plug-in, however, required a bit more aggressive application of color noise reduction that resulted in slightly less color noise removal, and a bit more loss of detail. When you look at the images at lower magnifications, though, there is little noticeable difference. Note that the I used the demo version of Noiseware (hence the watermarked grid) since I wrote this blog on my laptop.

Bottom line? Boundary Noise Reduction Plug-in is a terrific Freeware package and comes totally recommended. Since I have Noiseware already on my desktop, I'll continue to use it for my most critical image processing. However, I'll have no hesitations about using this Freeware package on my laptop or computer at work. If you are looking for a free noise reduction package then look no further.