Luminous Landscape Forum

Raw & Post Processing, Printing => Digital Image Processing => Topic started by: skibum187 on February 27, 2007, 03:07:36 pm

Title: Best way to smooth gradients?
Post by: skibum187 on February 27, 2007, 03:07:36 pm
So I have an image that has quite a bit of sky in it. I made the image into a duotone and now there are very harsh gradient lines in the sky. I figured they were just a product of my monitor profile, but they show up when I print as well. I've tried to make the sky a separate layer and applied gaussian blur, which helped a bit, but not enough. Any suggestions how to fix this problem?
Title: Best way to smooth gradients?
Post by: jjlphoto on February 27, 2007, 03:55:51 pm
Quote
So I have an image that has quite a bit of sky in it. I made the image into a duotone and now there are very harsh gradient lines in the sky. I figured they were just a product of my monitor profile, but they show up when I print as well. I've tried to make the sky a separate layer and applied gaussian blur, which helped a bit, but not enough. Any suggestions how to fix this problem?
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Try adding some noise rather than blur. (That's an old pre-press trick.)
Title: Best way to smooth gradients?
Post by: orangekay on February 27, 2007, 04:09:52 pm
Define a gradient containing all of the colors in the existing sky, mask out the foreground and apply.
Title: Best way to smooth gradients?
Post by: Jack Flesher on February 27, 2007, 04:52:43 pm
Re-process the image in 16-bit and keep it in 16-bit through the entire process...  That should eliminate your sky banding issues.
Title: Best way to smooth gradients?
Post by: orangekay on February 27, 2007, 06:32:49 pm
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Re-process the image in 16-bit and keep it in 16-bit through the entire process...  That should eliminate your sky banding issues.
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Unless it needed some seriously heavy duty adjustments that would stretch even 16-bit data too thin.
Title: Best way to smooth gradients?
Post by: 61Dynamic on February 27, 2007, 08:53:20 pm
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Unless it needed some seriously heavy duty adjustments that would stretch even 16-bit data too thin.
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Emphasis on the heavy duty part...

How did you convert to grayscale? The method used can have a negative effect on noise and posterization (*cough* desaturate). I'd guess the bit-depth would be the more likely candidate but it's difficult to say without seeing an example.
Title: Best way to smooth gradients?
Post by: Danijela D. Karic on February 28, 2007, 07:06:54 pm
Quote
So I have an image that has quite a bit of sky in it. I made the image into a duotone and now there are very harsh gradient lines in the sky. I figured they were just a product of my monitor profile, but they show up when I print as well. I've tried to make the sky a separate layer and applied gaussian blur, which helped a bit, but not enough. Any suggestions how to fix this problem?
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Hi,

Actually the best thing would be to post your image and then ask for solutions. I'm sure that way, most of us would get closer to the point and help you.

Regards
Danijela