RetouchPRO

Go Back   RetouchPRO > Technique > Photo Retouching
Register Blogs FAQ Site Nav Search Today's Posts Mark Forums Read


Photo Retouching "Improving" photos, post-production, correction, etc.

Gradation banding remedies?

Reply
 
Thread Tools
  #11  
Old 11-17-2011, 09:01 PM
shift studio's Avatar
shift studio shift studio is offline
Senior Member
 
Join Date: Feb 2009
Location: Calgary, Canada
Posts: 389
Re: Gradation banding remedies?

my favourite solution is the filter/brush strokes/spatter with radius 6-25 and smoothness = 1. It should break up any banding beautifully.
--shift studio
Reply With Quote top
  #12  
Old 11-18-2011, 01:45 AM
Repairman's Avatar
Repairman Repairman is offline
Senior Member
 
Join Date: Dec 2010
Location: Bristol UK
Posts: 683
Re: Gradation banding remedies?

Good link Mc and a neat trick Shift. Back in the day we used to output everything to 10x8 transparency - woe betide anyone who didn't pick up bands before output! The trick was to create a gradation using the same grey as start and end points; this would create a natural dither. Applying usm would 'pop' the grain after which you could make a contrasty B/W auto mask. LOL, retouching was more organic back then!
Reply With Quote top
  #13  
Old 11-18-2011, 04:50 AM
chet webley chet webley is offline
Member
 
Join Date: Oct 2010
Posts: 56
Re: Gradation banding remedies?

Quote:
Originally Posted by mcdronkz View Post
This might be an interesting read.
That is very interesting!
Reply With Quote top
  #14  
Old 11-18-2011, 08:19 AM
Chain's Avatar
Chain Chain is offline
Senior Member
 
Join Date: May 2009
Location: Oslo, Norway
Posts: 551
Thumbs up Re: Gradation banding remedies?

Quote:
Originally Posted by chet webley View Post
That is very interesting!
Absolutely. Well written tutorial, and a very clever trick (It simulates Photoshop's 16-to-8-bit dithering "realtime" while working in 16 bit to prevent you from seeing banding on your monitor that isn't really in the image).
Reply With Quote top
  #15  
Old 11-18-2011, 08:36 AM
Chain's Avatar
Chain Chain is offline
Senior Member
 
Join Date: May 2009
Location: Oslo, Norway
Posts: 551
Re: Gradation banding remedies?

Quote:
Originally Posted by shift studio View Post
my favourite solution is the filter/brush strokes/spatter with radius 6-25 and smoothness = 1. It should break up any banding beautifully.
--shift studio
I just tested this on an image (best radius depends on the width of the bands). It worked great.

Attached example from an 8-bit image (a real example I had a while back). Banding was caused by a gaussian blur in a blue area. Then I applied Spatter. I ran auto-curves just to pump the contrast for visibility afterwards.
Attached Images
File Type: gif spatter.gif (69.7 KB, 61 views)
Reply With Quote top
  #16  
Old 11-18-2011, 09:51 AM
shift studio's Avatar
shift studio shift studio is offline
Senior Member
 
Join Date: Feb 2009
Location: Calgary, Canada
Posts: 389
Re: Gradation banding remedies?

Quote:
Originally Posted by Chain View Post
I just tested this on an image (best radius depends on the width of the bands). It worked great.

Attached example from an 8-bit image (a real example I had a while back). Banding was caused by a gaussian blur in a blue area. Then I applied Spatter. I ran auto-curves just to pump the contrast for visibility afterwards.
I use it in real-world situations all the time to smooth out large, close-to-flat areas - skys, walls, backgrounds - the trick is it must not be applied in areas where there is too much difference spatially, or you'll see ugly artifacts.

I also use it on masks that have banding in them

I'm attaching another image I posted when this topic came up in the past as an example.

--shift studio
Attached Images
File Type: jpg BandingFix.jpg (88.2 KB, 66 views)

Last edited by shift studio; 11-18-2011 at 10:16 AM.
Reply With Quote top
  #17  
Old 11-18-2011, 12:53 PM
John Wheeler's Avatar
John Wheeler John Wheeler is offline
Senior Member
 
Join Date: May 2011
Location: Colorado
Posts: 583
Re: Gradation banding remedies?

Thanks shift studio

I really like your technique and have added that to my tool box. It is really helpful for adding effective noise to the banding to have that spatial component added and not just noise on each pixel. Also thanks for the heads up about using it in other areas than the banding. I tried that out and it really messed up higher contrast edges. Your technique with adding a mask to control where it is applied is an excellent approach!! It's a keeper
Reply With Quote top
  #18  
Old 11-18-2011, 01:45 PM
shift studio's Avatar
shift studio shift studio is offline
Senior Member
 
Join Date: Feb 2009
Location: Calgary, Canada
Posts: 389
Re: Gradation banding remedies?

Quote:
Originally Posted by John Wheeler View Post
Thanks shift studio

I really like your technique and have added that to my tool box. It is really helpful for adding effective noise to the banding to have that spatial component added and not just noise on each pixel. Also thanks for the heads up about using it in other areas than the banding. I tried that out and it really messed up higher contrast edges. Your technique with adding a mask to control where it is applied is an excellent approach!! It's a keeper
I'm glad to have helped/contributed.
--shift studio
Reply With Quote top
  #19  
Old 12-12-2011, 07:27 AM
Chain's Avatar
Chain Chain is offline
Senior Member
 
Join Date: May 2009
Location: Oslo, Norway
Posts: 551
Re: Gradation banding remedies?

I just used the technique for an image that had bad banding issues (mostly due to JPEG compression).

I refined the technique by layering several layers with different radius settings. For the large area I made the noise smoother by using radius 23, 24 and 25, and blending them evenly. Close to the edges of a foreground object I used an incrementally smaller radius (masked).

The only annoyance I encountered was that the filter doesn't work in 16-bit mode.

Last edited by Chain; 12-12-2011 at 07:42 AM.
Reply With Quote top
  #20  
Old 05-18-2012, 09:09 AM
delene delene is offline
Junior Member
 
Join Date: Nov 2010
Posts: 11
Re: Gradation banding remedies?

I have successfully used the spatter method for getting rid of banding on backgrounds in studio shoots but can anyone give me advice as to how to get a smooth transition from the subject (usually a baby crawling around!) as I always have difficulty in moving from the subject to the background.

Any advice on smooth transitions (generally using a mask) greatly appreciated!
Reply With Quote top
Reply

  RetouchPRO > Technique > Photo Retouching


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Gradient Banding Help nowheremanphoto Photo Retouching 11 06-08-2011 01:35 AM
Weird banding Brentnauer Photo Restoration 6 02-16-2011 10:22 PM
Removing banding texture. FFT Filter for MAC? SBNL Photo Retouching 12 12-15-2010 05:17 PM
banding... more complex the longer i work on the t tomasz.k Photo Retouching 31 12-10-2008 01:46 PM
Reconsidering 16 bit Ed_L Input/Output/Workflow 14 11-01-2005 10:41 AM


All times are GMT -6. The time now is 03:55 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
SEO by vBSEO ©2011, Crawlability, Inc.
Copyright © 2016 Doug Nelson. All Rights Reserved