mark_blackman1 Posted September 13, 2004 Share Posted September 13, 2004 I have several images (both B&W and colour) where I have foliage against a sky. When trying to add extra contrast to the sky I've used the magic wand tool (PS 7) to select the appropriate area. However, I can't seem to get it to select down to pixel level (setting feathering to 0 doesn't seem to help). The marching ants end up halo- ing the folliage leaving a pronounced fringe after working on the sky area. I *can* work round this by cloning and bluring with a tiny brush to remove the fringe but's teadious and the result is never satisfactory. Is there a better (and more accurate) way to do this? Link to comment Share on other sites More sharing options...
brainbubba_motornapkins Posted September 13, 2004 Share Posted September 13, 2004 This kind of problem is better dealt with at the outset by using a polarizing filter to darken the sky, and avoiding overexposure, though I have had some success at creating artificial blue skies, where the original was completely clipped to white. The magic wand is a pretty blunt instrument to use on delicate details. A couple of things to try: create a mask by copying and pasting the relevant area and increasing contrast of the alpha channel (perhaps with some manual cleanup), or select by color and experiment with different settings. As long as the sky has color and tonality (brightness) dictinct from the foloiage, with clean edges, either should work fairly well. When you have made the selection you can expand/contract it and then feather by a few pixels (depending on the resolution you are working at). This will take some experimentation to find the right settings. To speed that up, select a small area to experiment on. Something else that may work is a hue/saturation adjustment layer with tweaks to blues & cyans (sky), and greens & yellows (or whatever appropriate colors for your foliage). Be patient, it will take some time before you get an intuitive grasp of how best to handle this rather difficult and challenging task. Work with what you have, do not try to find resolution and precision that isn't already there. Link to comment Share on other sites More sharing options...
kymtman Posted September 13, 2004 Share Posted September 13, 2004 I agree with BrainBubba on the color select and use the eyedropper to select the ranges. Just tried it on a photo I was having difficulty with and it looks beautiful. Thanks BrainBubba! Link to comment Share on other sites More sharing options...
scott s Posted September 13, 2004 Share Posted September 13, 2004 In the past I've used the lasso to roughly cutout the tree and move it to a different layer. This allows for better control for selecting by color range, and the tree background goes to transparent. You can also add another layer behind the tree, pure black for instance, so any fringe pixels will show up better. Then you can change that pure black to a blue similar to the new sky. Now select the tree choose the Move tool, and use the arrow keys to move 1 pixel over and then back again. The selection will shrink to fit the non-transparent pixels which makes a neat selection around the tree. Now uncheck all other layers except the tree and blue, and Merge Visible and any halo pixels should merge towards the new blue. Select Inverse and delete the unwanted blue areas. Now you can merge the tree back to the original layer and it should have nicefringe pixels that will match the new blue sky. Here's a thread I wrote with some thoughts & comments about replacing skies in photos: http://photography-on-the.net/forum/viewtopic.php?p=234590#234590 Link to comment Share on other sites More sharing options...
scott s Posted September 13, 2004 Share Posted September 13, 2004 The above thread also includes an example before-and-after of a sky replacement I did. It came out pretty darn well I think. Link to comment Share on other sites More sharing options...
gary evans Posted September 13, 2004 Share Posted September 13, 2004 Or you can roughly select the tree, copy it to a new layer, use the background eraser to erase the sky from the new layer, adjust the background layer that contains the sky and place the layer with just the tree over top after you have adjusted the sky... Link to comment Share on other sites More sharing options...
kevin_dean Posted September 13, 2004 Share Posted September 13, 2004 try expanding the view to actual pixels, and then tick the contigious box before using the wand. Link to comment Share on other sites More sharing options...
mark_blackman1 Posted September 13, 2004 Author Share Posted September 13, 2004 Kevin, tried that. Below is an example of the issue. Hopefully you can see the ants - this is at pixel level. Link to comment Share on other sites More sharing options...
zapped Posted September 13, 2004 Share Posted September 13, 2004 Ron - you still need to be careful how you select the sky in the presence of foliage. There are a lot of spots in your "barnblue.gif" image where you missed the sky, leaving stray spots of blown sky (white) amongst the leaves. Here's a portion of your barn image with the problematic pixels highlighted in a bright pink: http://www.pbase.com/pricklypear/image/33786686/original.jpg Link to comment Share on other sites More sharing options...
kevin_dean Posted September 13, 2004 Share Posted September 13, 2004 Mark are you sure you had contigious ticked as I tried on your picture and it removed it all? just leaving your "ants" behind. Link to comment Share on other sites More sharing options...
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