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Photography Question 
Dan C.
BetterPhoto Member Since: 12/31/2005
 

Help with RAW - eliminating converging colors


 
 
Any help would be appreciated.

Shooting raw. How do I eliminate the blue lines in the high contrast areas where the white snow meets the dark background? In camera raw I have tried the lens tab and also tried to eliminate it with tweaking sharpness.

If anybody has had experience / success with this, I would appreciate your advice.

Thanks,
-Dan


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2/13/2006 10:21:38 PM

 
Dan C.
BetterPhoto Member Since: 12/31/2005
 
 
 
I tried to upload an image one the first post. Apparently didn't work. I will try in this post.


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2/13/2006 10:25:47 PM

 
Gregory LaGrange
BetterPhoto Member Since: 11/11/2003
gregorylagrange.org
  Buy a better lens. The different wavelengths are being seperated with lower quality optics. Sharpness will probably accentuate it.


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2/13/2006 11:25:03 PM

 
Jon Close
BetterPhoto Member Since: 5/18/2000
  Chromatic aberration. Yes, lens related, but with the fixed lens of the FinePix camera, your are limited to post-processing fixes or avoiding it in the first place. In the posted sample pic the effect is worse due to misfocus and overexposure.


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2/14/2006 5:51:50 AM

 
Dan C.
BetterPhoto Member Since: 12/31/2005
  is worse due to misfocus and overexposure

I'll have to look into that, possibly learning more. According to the original histogram, it was not overexposed. although the snow was a challenge against the dark background shadows, there were no blown highlights. the entire histogram (both ends) had nothing trailing off of either end - all were within the histogram. looking at the picture itself, it appears underexposed. perhaps I should post it here and get some advice.

Thanks for your help,
-Dan


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2/14/2006 5:57:33 AM

 
Christopher A. Vedros
BetterPhoto Member Since: 3/14/2005
  Dan,
Was this a tight crop taken from a larger image? Color fringes like this are often made worse when enlarging or cropping an image.

Also, like Gregory said, sharpening will usually make it worse.

In some images, you might be able to clean things up with the clone tool.

Chris


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2/14/2006 10:32:20 AM

 
Dan C.
BetterPhoto Member Since: 12/31/2005
  Chris,

Yes, it was a section I cut for illustration. It was blown up about 500% - 600% in photoshop. It's not as noticible in the image at normal enlargement, but it's there and it has to go.

Perhaps I'll upload the image it came from and the histogram. If Jon C. has the time, perhaps he could help with the overexposure thing.

Thanks,
-Dan


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2/14/2006 4:02:03 PM

 
Craig  Paulsen   you need a better lens(L-series) if you're serious.

If can afford it then maybe some WD40 :)


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2/14/2006 4:05:06 PM

 
Christopher A. Vedros
BetterPhoto Member Since: 3/14/2005
  If you were serious, you wouldn't suggest someone get a Canon L-series lens when they don't own an EOS camera.


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2/14/2006 5:47:10 PM

 
Dan C.
BetterPhoto Member Since: 12/31/2005
  you need a better lens(L-series) if you're serious.

Yes, I am serious about this. Unfortunately, I just can't afford a better camera right now. But I'm saving for it and when I can purchase it, I will. We all have to work within our limitations. Not much I can do about it.

Regards,
-Dan


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2/14/2006 7:22:01 PM

 
Dan C.
BetterPhoto Member Since: 12/31/2005
 
 
 
Jon (or any other),

I'm uploading the original image, with all defaults and the histogram.

I am working very hard to get very deep into the technical aspects of digital photography. Right now I am limited by what I have to work with, so I have to do the best I can with it.

In your comment you said part of the aberation was overexposure. That's one thing I can control. The histogram shows a little margin on the right side, so I don't see blown hightlights. But if there is something I can adjust to reduce the problem, I will. Should I move exposure down a little.

Thanks everybody.

-Dan


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2/14/2006 7:31:57 PM

 
Dan C.
BetterPhoto Member Since: 12/31/2005
 
 
 
Betterphoto hung when I got to the upload option. Here's the pic.


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2/14/2006 7:36:19 PM

 
Dan C.
BetterPhoto Member Since: 12/31/2005
 
 
 
Betterphoto hung when I got to the upload option. Here's the pic.


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2/14/2006 7:36:56 PM

 
Dan C.
BetterPhoto Member Since: 12/31/2005
 
 
 
Jon (or any other),

I'm uploading the original image, with all defaults and the histogram.

I am working very hard to get very deep into the technical aspects of digital photography. Right now I am limited by what I have to work with, so I have to do the best I can with it.

In your comment you said part of the aberation was overexposure. That's one thing I can control. The histogram shows a little margin on the right side, so I don't see blown hightlights. But if there is something I can adjust to reduce the problem, I will. Should I move exposure down a little.

Thanks everybody.

-Dan


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2/14/2006 7:40:26 PM

 
Dan C.
BetterPhoto Member Since: 12/31/2005
 
 
 
Jon (or any other),

I'm uploading the original image, with all defaults and the histogram.

I am working very hard to get very deep into the technical aspects of digital photography. Right now I am limited by what I have to work with, so I have to do the best I can with it.

In your comment you said part of the aberation was overexposure. That's one thing I can control. The histogram shows a little margin on the right side, so I don't see blown hightlights. But if there is something I can adjust to reduce the problem, I will. Should I move exposure down a little.

Thanks everybody.

-Dan


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2/14/2006 7:40:26 PM

 
Dan C.
BetterPhoto Member Since: 12/31/2005
  (sorry about that, folks when I pressed submit to upload the photo, betterphoto had a server error. don't know why it repeated that post).


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2/14/2006 7:49:43 PM

 
Christopher A. Vedros
BetterPhoto Member Since: 3/14/2005
  Dan,
I think the image is exposed very well. I think Jon read the first image as misfocus and overexposure because you took a very small portion of the image and enlarged it so much.

Have you tried printing it? The chromatic aberration that you see when you zoom in close might not show up much in a normal sized print.

If it does show up, you might be able to zoom in and use the clone tool or a blending brush to touch up some of the edges.

Nice picture, by the way.

Chris


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2/14/2006 7:54:54 PM

 
Gregory LaGrange
BetterPhoto Member Since: 11/11/2003
gregorylagrange.org
  If that were slr, skylight filter would lessen the overcast uv blue. Or decrease the blue on levels or curves. But it's still going to be there.


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2/14/2006 9:23:29 PM

 
Jon Close
BetterPhoto Member Since: 5/18/2000
  Yeah, what Chris said. I thought it was overexposed because of the lack of detail in the white areas. But now I see it's because of the extreme enlargement (500-600%). Still that's a difficult image to capture in a single shot. You've got extremely light and extremely dark tones with little inbetween (spikes at each end of the histogram). Because a camera's digital sensor (or film for that matter) have a limit to the dynamic range that can be captured, it is very difficult to get detail in the dark areas (pond, mill wheel) and in the bright white snow in one exposure. With a "still life" scene such as this one, you could take 2 exposures, one for the dark tones, and a 2nd for the bright areas, and combine them later with an editing program.


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2/15/2006 6:11:53 AM

 
John Rhodes
BetterPhoto Member Since: 2/24/2005
  Dan, the solution seems rather simple. You cannot expect a 5Mp camera's image to be successfully enlarged 600%. The original image is great.

John


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2/15/2006 6:12:43 AM

 
Jon Close
BetterPhoto Member Since: 5/18/2000
  More on blending 2 or more images to extend the dynamic range: http://www.luminous-landscape.com/tutorials/digital-blending.shtml.


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2/15/2006 8:26:52 AM

 
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