Approve the Cookies
This website uses cookies to improve your user experience. By using this site, you agree to our use of cookies and our Privacy Policy.
OK
Index  •   • New posts  •   • RTAT  •   • 'Best of'  •   • Gallery  •   • Gear  •   • Reviews
Guest
New posts  •   • RTAT  •   • 'Best of'  •   • Gallery  •   • Gear  •   • Reviews
Register to forums    Log in

 
FORUMS Post Processing, Marketing & Presenting Photos RAW, Post Processing & Printing 
Thread started 02 Jan 2010 (Saturday) 11:57
Search threadPrev/next
sponsored links
(this ad will go away when you log in as a registered member)

Noise Reduction: A primer on reducing noise with NeatImage

 
Guineh
I've been wisdom free for about 10 years, now.
Avatar
9,030 posts
Joined May 2006
Location: In a gilded cage
     
Jan 02, 2010 11:57 |  #1

More details are on my flickr stream starting with this image (external link).

Image with no noise reduction at all. This is extremely noisy because I pushed the shadows quite a bit to counteract the backlighting in the image. I did not use flash in this image, as I think it's kind of mean to the animals. Other people may not have the same moral objection to using flash, and may use flash freely. If it's one more bright flash the animal doesn't have to endure, then all the better.

IMAGE: http://farm3.static.flickr.com/2734/4237015199_1e85eee260_o.jpg


Using the built-in noise reduction in Adobe Camera Raw. This is the most you could ever hope for in ACR. Better, not not much better:
IMAGE: http://farm3.static.flickr.com/2653/4237015023_3f6c9bf6a7_o.jpg

Noise Reduction using NeatImage in an automated workflow. The chromiance noise has been eliminated, but the luminance noise is quite strong. This is mostly due to NeatImage's poor choice for a profiling zone. It chose the white area in the background of the image, which does not exhibit much noise at all:
IMAGE: http://farm3.static.flickr.com/2757/4237790506_8ff9910d63_o.jpg

NeatImage in a manual workflow. Essentially, the PS Script stops at the noise reduction step allowing the user to intervene, allowing the noise reduction algorithm to get optimal results. By choosing a more representative area of noise (in this case, the bird's chest does not contain much detail, so is a good candidate) Simply by choosing a better area to profile from improved the image greatly, but left some speckling, so tweaking the high-frequency and luminance noise levels, I was able to virtually eliminate all speckles left over from the noise reduction process, giving a much cleaner final image:
IMAGE: http://farm3.static.flickr.com/2795/4237014955_3453d45815_o.jpg

All images were processed using a batch script, only changing how noise reduction was applied. As part of this processing, sharpening using the Smart Sharpen filter in Photoshop is applied after downsizing to help counteract some of the softening that normally occurs when the image is resized.

The drawback, of course, is any noise reduction algorithm will attack details, so a balance must be struck between acceptable noise levels and noise reduction artifacts (e.g. Plastic appearance, softening, and loss of color saturation)

There are other choices for adaptive noise reduction available. Any adaptive noise reduction package will work. I have used NeatImage for a few years, and prefer that package over others. The key is to choose a package that uses an adaptive algorithm (such as Neat Image) these algorithms will require a profiling step using a sample from the image (or another image) to calculate the exact nature of the noise produced by the camera. It should allow the flexibility to adjust the reduction and estimation levels in separate channels, and separate frequencies to optimize the amount of nose that will be removed.

There are trade-offs of course. You will need to balance the amount of detail that will be retained to the amount of nose that will remain in the image. Even the best algorithms will have this trade-off.

I hope this post gives you some insight into reducing noise in your images. Comments are appreciated, and feel free to post questions as well.

Everything should be made as simple as possible, but not simpler - Albert Einstein
7D, 40D, Sigma 10-20 EX HSM, Tamron 17-50 f/2.8 SP XR Di II, EF 50 F1.8, EF 70-200 f/2.8L IS, Sigma 1.4x TC, Kenko Tubes, Sigma EF-500 DG ST Flash
Flickr (external link) - Blog (external link)

  
  LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as a registered member)

1,314 views & 0 likes for this thread
Noise Reduction: A primer on reducing noise with NeatImage
FORUMS Post Processing, Marketing & Presenting Photos RAW, Post Processing & Printing 
AAA
x 1600
y 1600

Jump to forum...   •  Rules   •  Index   •  New posts   •  RTAT   •  'Best of'   •  Gallery   •  Gear   •  Reviews   •  Member list   •  Polls   •  Image rules   •  Search   •  Password reset

Not a member yet?
Register to forums
Registered members may log in to forums and access all the features: full search, image upload, follow forums, own gear list and ratings, likes, more forums, private messaging, thread follow, notifications, own gallery, all settings, view hosted photos, own reviews, see more and do more... and all is free. Don't be a stranger - register now and start posting!


COOKIES DISCLAIMER: This website uses cookies to improve your user experience. By using this site, you agree to our use of cookies and to our privacy policy.
Privacy policy and cookie usage info.


POWERED BY AMASS forum software 2.1forum software
version 2.1 /
code and design
by Pekka Saarinen ©
for photography-on-the.net

Latest registered member is Glennalvord
683 guests, 226 members online
Simultaneous users record so far is 15144, that happened on Nov 22, 2018

Photography-on-the.net Digital Photography Forums is the website for photographers and all who love great photos, camera and post processing techniques, gear talk, discussion and sharing. Professionals, hobbyists, newbies and those who don't even own a camera -- all are welcome regardless of skill, favourite brand, gear, gender or age. Registering and usage is free.