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gmwinder
8th of December 2007 (Sat), 13:34
I have been asked to make some prints of some golf holes where the sky looks overcast. Unfortunately the originals are jpeg files, not RAW. Anyone have any ideas how I can replace/change the overcast sky with something more natural (blue)?

Thanks,

Gary

gmwinder
8th of December 2007 (Sat), 13:35
Oops...forgot to add the picture

JakPot
8th of December 2007 (Sat), 13:45
i think a place to start is making a mask (try copying the green channel), then boosting the levels to make everything you want to keep the same black (and the sky to replace white). depends on your PS skills, this is kind of advanced & sometimes takes some manual brush work to get it looking right.

Then you'll be able to drop a new sky into the picture while keeping the trees where they are and still getting new sky behind them. It may be tricky with the CA (or fringing) in the trees.

unless someone knows a better solution, give it a shot!

SilverHCIC
8th of December 2007 (Sat), 14:26
sometimes takes some manual brush work to get it looking right.




That'll work, but as you said, some manual brush work will be involved due to the sky showing between some of those trees, especially where the branches cross each other and are kinda tight. Would have been a bit easier if you had bracketed the shots to get a properly exposed sky, then no color substitution would be needed, just the mask. ... Still, a bit of manual brushwork between the branches would be necessary. The sky in this shot is just so blown out, there's not much to work with. Perhaps somebody else has an idea that can replace the sky w/o relying on a straight mask/reveal technique. :(

Dan Roeder
8th of December 2007 (Sat), 18:29
Here's a link to an interesting tutorial (Photoshop Workbench at Radiant Vista web site) where he replaces the blown out sky in the background with a shot of a mountain.
http://www.radiantvista.com/workbench/anurag-from-india-2

Basically, he brought the mountain in as a separate layer and used the Darker Color blend mode.

JakPot
8th of December 2007 (Sat), 19:26
here's a REALLY quick example using the method i described. I did no brush work in the trees, so you can see the result & why it will take a while to get this right.

depending on the number of images, it may be easier to try to retake these at some point.

http://www.msprotege.com/members/TigrMsP/example.jpg

gmwinder
8th of December 2007 (Sat), 19:55
Jakpot...you've given me some inspiration! I don't really have a chance to retake. This is a course in Bethlehem, PA called Saucon Valley. Some members flew me there from Michigan during the summer on their private jet to play golf and take some pictures for them.

Gary

JakPot
8th of December 2007 (Sat), 20:29
Jakpot...you've given me some inspiration! I don't really have a chance to retake. This is a course in Bethlehem, PA called Saucon Valley. Some members flew me there from Michigan during the summer on their private jet to play golf and take some pictures for them.

Gary

sounds like a great deal to me! let us see the outcome. keep at it!

Canonymous
8th of December 2007 (Sat), 20:45
226726

In photoshop I created a new layer, used the gradient tool to add a blue overlay to transparent and set its overlay mode to 'multiply', then using the green channel, I made a mask to mask out the trees. Added some slight contrast to the highlights using shadow/highlights tool.
226727;)

David

SilverHCIC
8th of December 2007 (Sat), 21:52
226726

In photoshop I created a new layer, used the gradient tool to add a blue overlay to transparent and set its overlay mode to 'multiply', then using the green channel, I made a mask to mask out the trees. Added some slight contrast to the highlights using shadow/highlights tool.
226727;)

David
Sweet. ... You win.
Using a green mask to ignore the trees was a slick idea. ;)

SilverHCIC
9th of December 2007 (Sun), 00:40
Using David's technique, I used a different sky mask that had some clouds. This helps match the white reflection in the water since the original photo had an overcast sky that was blown out. ... Great idea David.

Anke
9th of December 2007 (Sun), 01:06
Using David's technique, I used a different sky mask that had some clouds. This helps match the white reflection in the water since the original photo had an overcast sky that was blown out. ... Great idea David.


Well remembered about the reflection, most people would miss that and it unbalances the shot otherwise.

jmik26
9th of December 2007 (Sun), 12:14
Try color range tool, it has been my friend since I learned how to use it. Link to thread on this... (http://photography-on-the.net/forum/showthread.php?t=408809&highlight=color+selection)

Lowner
9th of December 2007 (Sun), 16:33
Another way of doing this in Photoshop (are'nt there always a 1001 ways?) is to select "darken" as the blending mode on the new sky layer.

With a plain white sky its works very well. It does need a quick spin round with the eraser set to a fairly large brush to remove "sky" from lighter bits of the foreground, but it deals with the fiddly bits between foliage beautifully. Its not so good on a sky with some detail, because this tends to show through.

If the new sky is too brutal, just play with the opacity slider.

Richard

gmwinder
10th of December 2007 (Mon), 21:22
Wow....you guys have given me some excellent solutions since I have about four shots I need to fix.

Thanks to everyone especially Dan Roader for turning me on to Radiant Vista!

Gary

gmwinder
14th of December 2007 (Fri), 22:11
I found a technique using Smart Objects....what do you think?

gary

PhotosGuy
15th of December 2007 (Sat), 11:50
More ways - see the video tutorial in post #8:
Tough Exposure question (http://photography-on-the.net/forum/showthread.php?t=421009)