
Above: This is the source plate that pluginz.com provided for the matte contest. A couple of things right away struck me as something I wanted to change: first, I wanted to get rid of the sky
since it’s so messy and overbright - second, I wanted to change the mood of the picture to sunny. That specific mood was the overall guideline when plotting out a course to go - and third: I wanted to try my hand at doing an integration of a 3d element.<br>

Above: First thing I do, is resizing to a nice big 4000 pixels wide - which was incredibly stupid, since the original resolution was 2048 wide! Gaah, what a moronic mistake, right out the gate! Rescaling at a factor of not 50% or 200% (25, 400, etc…) will lose your detail and add stuff that Photoshop just makes up, because of the image interpolation that happens in the scaling. (I dunno what I was thinking…sigh…)
Anyways. I paint out that big tree in the foreground - I want to add something into that space, so I need it cleaned.
You can clearly see that I’ve cloned my way through this, and that it’s not very pretty. I’ve tried to show a bit more clearly how this can be done in the video below. Please forgive a few slipups and few bad spots in the sound recording - I’m ad-libbing this stuff and make a few mistakes in calling the ‘clone stamp’ ‘colour stamp’ and so forth 

http://extraball.sunsite.dk/mogens/cloning.zip
Below: The next step here is altering the entire colour palette of the image a bit. I don’t want it this green, since what I’m going for is a sunny image - in my mind, sunny means a lot more yellow and warm than what we have here. One simple solution is to selectively shift the hues

Above: In the image we have 1: the source plate, which I’m first modifying in 2: Using the hue/saturation adjustment panel, I’m shifting all colour ranges (notice it says ‘Edit: Master’ at the top. You can select different colour ranges in this dropdown menu). Image 3 is the result.
This isn’t a bright, sunny landscape yet - and that’s not what the aim is here. The aim is simply to turn the hues towards a warmer landscape - I guess you could think of a sunny day, but overcast
Notice the background mountains and the lake are tilted too far towards cyan… very psychedelic. I want that turned back, so I open the hue/saturation adjustment panel again, and this time select ‘cyan’ in the Edit dropdown menu. This will only affect colours in the range defined as ‘cyan’ now - which of course won’t always work for blues, since they might be in the range defined as either blue or magenta as well. For this, you’ll have to try and see. Image 5 is the result - a slightly warmer landscape, but still with the blue-tinted lake and hazy mountains.

Above: This was the actual hueshifted version I used.

Above, I’ve painted over a bit of the lake - I was just experimenting with the way it looked, really. The main thing I’ve done here is to add a mask for the sky. The reason I’m doing this is that I wanted to change the image to a sunny one, which of course also calls for a sky replacement. Rather than having to paint carefully so as to not paint over any background elements, I might as well just create a mask to paint within. A lot of people use quickmasks, but I’m more partial to using layers with the ‘preserve transparency’ option turned on.
I’ve captured a short video clip of various masking techniques, which you can download below.

http://www.skjoldbroder.dk/masking.zip
I hope noone takes offense at my little wisecrack about ‘grads’ VS ‘gradients’ - it seems like that’s the LA slang for gradient; I’ve certainly heard it said a few times, but I of course have nothing but respect for the matte artists in question. If you want to get back at me, you can always hit me about that ‘quickwask’ I’m talking about in the beginning of this video.