Most digital files show noise at high ISO but also at low ISO in the the deep shadows. Noise removal can be tricky and also very time consuming if you use advanced tools like Neat Image.

We most of the time stay away from noise removal. How? We use low ISO values and a tripod. Of course we know that this is not an option all the time.

Here is an example from our recent trip to New York

Fire Station in Greenwich

Although this is only a ISO 200 shot with the Canon 300D there is a lot of noise in the shadows. Most likely this noise will also show up as grain on larger prints (13x19" or even less). This image lets me want a noise removal tool that is at least in the class of Neat Image but easier to use and also faster.

Looks as if Noise Ninja fits the bill.

Out of the blue I got a version of Noise Ninja from it's author Jim Christian. The fire station was just the right image to test Noise Ninja's abilities.

But first let me list some issues that we hope get solved in the near future:

• Stand alone application (we only accept this if the benefit clearly outweighs the hassle: it does) - a PS plugin is planned
• Windows only: Mac version is planned
• Does not keep profiles attached to the images: Planned to fix

You probably guess right that I will only start with the critical remarks if the rest is more than just interesting.

How does Noise Ninja work?

Here is a crop from the original:

unfiltered (100% pixels)

This kind of noise is hard to show at only 100% so you better open it in PS and look at 200-400%.

Here are the steps to follow in Noise Ninja:

1. Open file (no LZW compressed files supported yet)

2. Load profile

Profile Tab

We did not even go into the details to understand the different settings as we just grabbed one of the profiles that come with Noise Ninja:

Current Profile Selection (multiple ISO per camera)

The profiles provided with Noise Ninja are free. More profiles are planned to be added. Users are encouraged to share their own profiles. There is even a clear more methodical way to create own profiles (won't touch this here). In this case we used a 400 ISO profile for the 10D (very close to the 300D) for our picture.

3. Select Filter tab

Filter Tab

We did not change anything here and just hit the "Remove Noise Button". But you also can tweak the sliders and preview the filter effect in a selectable crop on the screen:

The green area shows the filter effect (here at 200% pixels)

Now Noise Ninja performs the filtering. We did not measure the speed but it seems much faster than Neatimage.

You have now both the filtered and the original image in the buffer and can switch between these versions to review the result.

4. Touch-up (Optional)

Touch-up

Here you can use some painting technique to perform a selective noise removal. We would use techniques in PS to get the same results by making the filtered image a new layer and adding a layer mask.

Here is the resulting image (crop):

filtered (100% pixels)

We were impressed because it keeps a lot of details while smoothening the image.

• Open raw converted images in PS CS (either C1 or ARC 2.0)
• Duplicate Layer and use Shadow/Highlight to improve shadows, highlights and midtone contrast
• Duplicate image in PS
• Flatten layers
• Save file as a ZIP compressed TIF (not LZW)
• Open file in Noise Ninja (running at the same time as PS CS)
• Load noise profile
• Filter image
• Save as ZIP compressed TIF
• Open file in PS
• Select All
• Copy image
• Close file
• Create new empty layer for the original layered file
• Paste filtered image into this layered file

As you can see there is lot of room for workflow improvements but at this time we don't know any better option.

On topics like noise removal or sharpening we always consult some of our editorial team members. My main advisors for noise removal and sharpening are Paul Caldwell and Jim Collum. With Jim I communicate on a nearly daily basis and Paul always helps me out when I review new major tools. We are also in permanent discussions with many other image processing experts and filter their feedback.

This is also a good place to thank both Jim and Paul for their friendship and great help!

Here are Paul's first impressions:

• First brush is that this tool has figured out the one thing that Neat Image never could, i.e. speed. I ran all the tests on an older W2K machine 850Mhz, 512MB of ram.
• I worked three separate images, all ISO 200 or 320. All 8 bit, I haven't tried it on 16 bit images.
• I used the filters provided for the 10D, and found them to be acceptable to the 1ds images. Haven't had a chance to try a custom filter setting as I did with Neat.
• The tool provides a much better low noise/high detail ratio. I found that on even images that had high sky noise, I was able to pull the noise down to an acceptable level and still have good details except for the finer edges.
• Speed, well we both know that. It's great. I worked on all 32mb 8 bit images, not 16 bit. I still need to try it against my big 72 to 96mb 3 segment stitches. I was able to complete a scan of an image in around 3 minutes with this machine, something that would have taken neat over 10.
• The program is memory intensive and processor intensive, however it can still run in the background while PS is open and not effect other program operations.
• I like that they allow for a default to "*_filterer" in the naming of a cleaned image as Neat does, This just makes the file easier to track later.
• Only issues I have are that it's a stand alone program and thus can't be integrated into a PS workflow or faded as a filter can. I realize you can layer the treated image and then either mask or fade then, so its not that big a deal.

Noise Ninja comes in two versions (we are an affiliate):

PC

Mac