Separate adjustment areas

A
Posted By
andrewp
Aug 24, 2003
Views
303
Replies
3
Status
Closed
I have been adjusting several landscape images that have needed two separate adjustments for foreground and background (eg washed out skies and color correction to the remainder) but in doing so have often ended up with an artificial look along the boundaries of the regions. Adjusting feathering values does make a difference but does not eliminate the effect totally and I have at times resorted to adjusting the problem area pixel by pixel.

In its simplest form the problem can be seen by selecting a region of an image (eg the sky) and adjusting its output levels to zero. Next invert the selection and again adjust the output level to zero. The result is not a totally black image but a black background with a narrow line along the boundary of the two regions, probably in the color of the original image.

Can anyone suggest a solution to the above?

Thankyou
Andrew P.
Related Tags
adjust area separate

How to Master Sharpening in Photoshop

Give your photos a professional finish with sharpening in Photoshop. Learn to enhance details, create contrast, and prepare your images for print, web, and social media.

MR
Mike Russell
Aug 24, 2003
One solution is to not use a selection at all.

From what you’re saying it sounds like you’re using Levels. Levels is like curves with one control point, which is why it is not possible to make fancy shapes to correct two things at once: making the sky darker always makes the land darker.

So use curves. To deal with a washed out sky, add three control points to the curve, spaced equally. Then drag the lighest of the three points (up or down, depending on your curve setup) of the curve to darken your sky.

You will then be free to color correct both the sky and your image using the individual channels. Masking is sometimes necessary, but the majority of images do not need it. The final result, as you’ve found, will look more natural if no mask is used.

The mask behavior you describe is how masks are supposed to work. Think about it. Suppose a black pixel is 50 percent selected. Deleting will result in a value of 128. Inverting the selection (to 50 percent) and deleting yields a final value of 64, not zero.

If you still want to use a mask, you can avoid this problem as follows. Use an adjustment layer with a layer mask created by curving a copy of the b channel in Lab mode, or whichever channel you decide separates the sky from the land best. Clean up the mask if necessary manually using Photoshop’s brush tools. The mask should be white for the sky area. Then add a curves layer on top of the masked curves layer. Use the second curves layer to correct the land first, then go back to the masked sky curve and adjust it to make the sky look good.

—

Mike Russell
http://www.curvemeister.com
http://www.zocalo.net/~mgr
http://geigy.2y.net

wrote:
I have been adjusting several landscape images that have needed two separate adjustments for foreground and background (eg washed out skies and color correction to the remainder) but in doing so have often ended up with an artificial look along the boundaries of the regions. Adjusting feathering values does make a difference but does not eliminate the effect totally and I have at times resorted to adjusting the problem area pixel by pixel.

In its simplest form the problem can be seen by selecting a region of an image (eg the sky) and adjusting its output levels to zero. Next invert the selection and again adjust the output level to zero. The result is not a totally black image but a black background with a narrow line along the boundary of the two regions, probably in the color of the original image.

Can anyone suggest a solution to the above?

Thankyou
Andrew P.
W
wes
Aug 24, 2003
Could you get the results you want by making a layer mask out of the sky selection and then doing a Gaussian blur on that in order to smooth out the edges? Or if blur doesn’t work, try other changes to the mask.

"Warren Sarle" wrote in message
"andrewp" wrote in message
I have been adjusting several landscape images that have needed two separate adjustments for foreground and background (eg washed out skies and color correction to the remainder) but in doing so have often ended up with an artificial look along the boundaries of the regions. Adjusting feathering values does make a difference but does not eliminate the effect totally and I have at times resorted to adjusting the problem area pixel by pixel.

In its simplest form the problem can be seen by selecting a region of an image (eg the sky) and adjusting its output levels to zero. Next invert the selection and again adjust the output level to zero. The result is not a totally black image but a black background with a narrow line along the boundary of the two regions, probably in the color of the original image.

Can anyone suggest a solution to the above?

Expand one or both selections using Select->Modify->Expand or Quickmask.
A
andrewp
Aug 25, 2003
Thank you for the quick responses. Also, my apologies about the dual posting – my ISP rejected my first message because of an unacceptable dummy email address. Unknown to me they still sent the message to his group..
For Mike Rusell – yes I had been using levels. I had selected the sky areas with the magic wand etc and applied the changes to that area, then inverted the chosen area and applied levels or other tools to the rest of the landscape. I will use your suggested approach. Thank you.

AndrewP

MacBook Pro 16” Mockups 🔥

– in 4 materials (clay versions included)

– 12 scenes

– 48 MacBook Pro 16″ mockups

– 6000 x 4500 px

Related Discussion Topics

Nice and short text about related topics in discussion sections