RetouchPRO

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


Image Help Got a problem image? Don't know where to begin? Upload images and ask our users what they think or if they can help

help to get rid of magenta cast

Reply
 
Thread Tools
  #1  
Old 06-09-2006, 03:40 PM
Cyber Cat's Avatar
Cyber Cat Cyber Cat is offline
Member
 
Join Date: Jul 2005
Location: New York
Posts: 96
help to get rid of magenta cast

hello, .... just came back from puerto rico (picture pirfect place), but not for me i know everything depp. on the camera used ,but im not a photographer so i used regular cheap camera (its not even digital), so back to the point ... got back my images and what a shock ...90% of images have magenta cast , no matter what i did to 'em it didnt turn out to be even close to what was happening at the time when photo was taken. according to the images time of shot is around 7 or 8 pm, but in actuallity it was taken around 2 or 3 pm.
sooooo, please help me....
oh, and noise allover the image as well.
larger image here: http://cherrydust.com/Luquillo_beach.jpg

thank youuuuuuuuuuuuuu
Attached Images
File Type: jpg Luquillo_Beach_PuertoRico.jpg (95.7 KB, 86 views)
Reply With Quote top
  #2  
Old 06-09-2006, 03:51 PM
philbach's Avatar
philbach philbach is offline
Senior Member
Patron
 
Join Date: Mar 2003
Location: Belgium, Wi
Posts: 1,332
Magenta

Well I switched the photo over to lab and then used the color sampler in photoshop to sample the clouds and decided they were gray with no cast. So using curves on the a and b channels I adjusted the color of the clouds to neutral.

I don't know if this what you saw at the time but that is how I corrected or at least changed your photo.
Attached Images
File Type: jpg beach.jpg (28.2 KB, 97 views)
Reply With Quote top
  #3  
Old 06-09-2006, 04:39 PM
Cyber Cat's Avatar
Cyber Cat Cyber Cat is offline
Member
 
Join Date: Jul 2005
Location: New York
Posts: 96
Dear Phil, thank you, looks amazing.
off to follow your steps
Reply With Quote top
  #4  
Old 06-09-2006, 04:56 PM
Daviskw's Avatar
Daviskw Daviskw is offline
Senior Member
 
Join Date: Apr 2006
Posts: 728
Hi there

I color corrected then added a little color to the sand and replaced the sky

Butch
Attached Images
File Type: jpg scan00031.jpg (26.0 KB, 74 views)
Reply With Quote top
  #5  
Old 06-09-2006, 09:14 PM
JuliPhotography JuliPhotography is offline
Junior Member
 
Join Date: Jun 2006
Location: North Carolina
Posts: 3
Phil,
May I ask why you chose to color correct with lab color instead of RGB. The image looks a lot better.
Thanks.
Reply With Quote top
  #6  
Old 06-09-2006, 09:33 PM
byRo's Avatar
byRo byRo is offline
Senior Member
 
Join Date: May 2004
Location: Goianésia, Brazil
Posts: 1,609
Normally auto-levels will give you a good start when fixing a photo like this. However if you try that nothing happens.
Auto-levels works by fixing the extreme points. If you look at the left edge there's a white border and so Auto-Levels will fix that and not even see your photo.

- I put in a Levels layer and selected the grey point on the sand. That left things still slightly blue so, still in Levels, I nudged the Blue gamma slider to taste;
- The image seemed to need a bit more colour, so I put in a Hue/Saturation layer and increased the Saturation a touch (+30%);
- A look at the Histogram shows the photo with lots of Highlights, some Shadows and hardly any mid-tones. A quick fix here is to duplicate the layer and run Image>Adjustments>Equalize, back off the opacity until you get a good result;
- Still seemed to be lacking colour, but increasing the saturation more resulted in harsh blues and yellows. So changed to LAB mode and with a Curve tweaked the mid-part (only) of the B curve.

Took a lot longer to write than to do!

Attached Images
File Type: jpg Luquillo_beach_byRo.jpg (96.5 KB, 67 views)
Reply With Quote top
  #7  
Old 06-09-2006, 09:46 PM
byRo's Avatar
byRo byRo is offline
Senior Member
 
Join Date: May 2004
Location: Goianésia, Brazil
Posts: 1,609
Quote:
Originally Posted by JuliPhotography
Phil,
May I ask why you chose to color correct with lab color instead of RGB. The image looks a lot better.
Thanks.
Hi there Juli, welcome to RetouchPRO.

Hope Phil doesn't mind if I reply...

Without going into too many details: In LAB the Lightness information (greyscale image) is in a separate channel to the colour information (which is in A and B). This means that any adjustments that you do to the colours, won't affect the Lightness.

In RGB things are different. The Lightness is a mix of the information in all three channels, and perceived colour is another mix of the three. Which means that if you adjust the colour, chances are that the Lightness will get ..er.. mixed up.

So that's why, in general, LAB is a good option for doing colour adjustments.

Reply With Quote top
  #8  
Old 06-09-2006, 10:44 PM
mistermonday's Avatar
mistermonday mistermonday is offline
Moderator
Patron
 
Join Date: Dec 2005
Posts: 3,028
Hi Cybercat, I get so many of these types of images that I have tried to come up with some techniques / actions that work well on a range of similar images that I can save a lot of time and batch them. This image happened to work quite well.
The sequence was as follows:
Equalize the image first (Image>Adjust>Equalize)
Do a Shadow Highlight Adj (Image>Adjust>Shadow Highlight) Default values 50/50/30.
This next step is not always necessary but often with underexposed images there is a lot of noise, so at this point I run Noise Ninja to smooth out the noise before the las step.
Next Image>Adjust>Match Color and just check the Neutralize box with no other settings.
The image come pretty well back into range for me. As a final tweak I took the image into LAB and did a minor curve adjustment to reduce the magenta by a few points (A channel) and increased the yellow by a couple (B channel).
Regards, Murray
Attached Images
File Type: jpg Luquillo_beach Rev MM Thumbnail.jpg (90.3 KB, 57 views)
Reply With Quote top
  #9  
Old 06-10-2006, 12:24 PM
Cyber Cat's Avatar
Cyber Cat Cyber Cat is offline
Member
 
Join Date: Jul 2005
Location: New York
Posts: 96
philbach, Daviskw, byRo, mistermonday i cant thank you enough for helping me. now with your guidance i can try to save rest of the images.
Reply With Quote top
  #10  
Old 06-10-2006, 01:19 PM
Dallas_TX's Avatar
Dallas_TX Dallas_TX is offline
Junior Member
 
Join Date: Aug 2004
Location: in front of my computer. Duh
Posts: 11
a simple no-nonsense approach.


Really funny author too.
Reply With Quote top
Reply

  RetouchPRO > Technique > Image Help


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
Removing Color Cast By the Numbers Possible? jojaspi RP Tutorials 6 09-28-2007 07:50 AM
I need help to check on colour cast Zeckson Image Help 13 07-26-2007 10:06 AM
Magenta cast when printing cahn Hidden Power Support 7 01-01-2007 11:28 AM
Correcting a scanned slide color cast Dan1335 Hidden Power Support 2 03-08-2006 02:10 PM
Epson 2450 and Magenta cast G. Couch Input/Output/Workflow 10 02-01-2002 02:22 AM


All times are GMT -6. The time now is 03:48 AM.


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