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View Full Version : How to convert white sky into blue?


PTAH
09-01-2003, 07:50 PM
Well I'm just a begginer in photography and I think I'm not going to be a profesional, as its just a hobby now. So as a begginer I can't solve that problem when a camera focuses color balance so that things are well seen in fron of the cam and the sky in the background focuses on white :(
So how could I fix it on Photoshop? Well I have tried to select all that "white sky" and apply a gradient of blue to it, but it looked so unnatural :-\, maybe you even now the color formula (rgb), which I could use?

AdrianW
09-01-2003, 10:27 PM
I tend use Select/ColorRange to grab the sky, usually with anti-alias on. If you've grabbed any of the rest of the image accidentally just use Alt-Lasso to deselect it. Copy the sky to a new layer. Then I use Image/Adjust/HueSaturation to make the layer blue - click Colorize, then move the Hue slider until things look right to you! Say, 184, 50, -15 - paler is better because if your selection wasn't 100% it's less noticeable ;-)

One of the biggest problems is you often end up with a pale halo around the sky where it was selected - consider either using the Burn Tool to soften that part of the image, or selective lasso brightness/contrast adjustments.

dsidwell
09-06-2003, 08:52 AM
I sometimes use the Selective Color and select the whites, then add black and shift the hue to blue, but this also can leave pale halos. It's best to wait for the right kind of sky!

bodinux
09-27-2003, 10:00 AM
I use the Gimp (the open source freeware great image editor) because I have no money to buy the other one. There is a real cool tool called : color rotation (to change a set of colors into another set or to apply some color to greys and whites). I used it for my pictures and it's a real great tool.

acrylonithrill
11-04-2003, 06:45 AM
Hii, I'm a newcomer in TE. I started photography about 6 yrs ago. What I normally find is that this problem is inevitable. One of the easier way with PS is to create a new layer with the sky "Lasso-selected" and pour in one saturated pastel blue or gradient sky blue. Fiddle around with the transparency and you can get a 90% natural color.

Darren
11-04-2003, 03:32 PM
It's not within the guidelines of trekearth, but for personal shots that I want to have printed, I actually have quite a large number of skies I have taken photos of in the past. When I find a shot I like, but with a dull, grey sky, I will choose everything in my original shot but the sky and the copy it(cntl-C). I then past it on top of the new and improved sky as a layer. If there are spots(usually leaves of trees) where the two photos clash, I can sometimes use the erase tool on the second layer, and erase the offending bits. This works best of course if there are fairly straight deliniation between foreground and sky, but I have even had some luck when there are a number of leafy trees(that is where you really need the eraser tool). I find the secret to making this work is to find a sky which matches closely enough to the characteristics of your photo. By taking a bunch of sky shots, from all different angles, at different zoom lengths, different times of day, different amounts of cloud cover, etc, etc, etc you can really help your chances. Somewhere I have a CD of about 200 different shots of the sky I have taken. Again, it might not be photographically honest, depending on your feelings on manipulation, and it doesn't really qualify for shots on TE, but for other circumstances, it can be a nice help.

Assuming you are shooting digital, I would suggest taking a number of shots of nothing but sky(or perhaps if you have some overhanging branches, that can act as a nice frame). Again, shoot from all angles, and all zoom lengths. Don't forget to take shots in the portrait mode as well, as it will look strange if you paste to a sky taken from the wrong orientation. If you give yourself enough options, you will be surprised how well you can make the two match.

ronners
11-04-2003, 11:13 PM
Guys,

The obvious solution is to try to come up with a photo which doesn't have a washed out sky. Most of the time, the sky won't just be pure white, but exposure compromises made by many cameras will fail to capture subtle shades of gray.

There are a couple of alternatives if it's a critical shot -

1. underexpose the shot (try a few different variations)
2. take two (or more) exposures and blend the one with the well exposed sky with another one with a well exposed landscape

Try to take the failings of your camera into acocunt before shooting - not just after.

Ron.

sykonico
11-11-2003, 05:22 PM
Thanks Ron,
That's exactly the kind of advice I was talking about in my thread the other day.

Nicolas

dawekato
12-10-2003, 02:00 AM
I agree the best way is to avoid taking a grey or bald sky. Of course, sometimes it can't be avoided. There are several things you can do with bad-looking sky:
1. Shoot the picture without the sky
2. Use a graduated neutral density filter to darken the sky. This filter is dark grey at the top and gradually fades to clear. The Cokin brand can be adjusted as high or low as you want.
3. Include a "frame" of overhead leaves, the arch of a building, anything to cover the sky in the picture.
If you do end up with a grey or bald sky, you can pour in blue to fill it. On Photoshop there is even a filter>render>clouds option.

dsidwell
12-20-2003, 11:48 PM
I have had limited success with using gradients, too. Duplicate the layer, then add a blue-to-transparent gradient. Adjust the percentages and length of the gradient until it looks decent. You can also adjust the new layer's opacity. This usually is best used when making a white sky a pale blue, and some blue will probably get on your foreground, too, if you're not careful.

You can also use several layers, select the sky on one of them without the foreground, apply a gradient, and flatten later.

Opus
12-29-2003, 10:03 PM
So, let me get this straight. I can make a gray sky blue, but if I add clouds I get chastized for posting a fake image?