The curves tool is a mighty powerful tool for enhancing your photos. A lot of people don't know how to use this tool, this is sometimes because they practice by opening the control box and moving the curve all over the place, don't like the result, and resign themselves never to touch it again. So, what can the curves tool do. It can, all in one tool, adjust contrast or tonal balance of the entire picture, adjust contrast of a small range of the picture say by darkening shadows and leaving lighter areas untouched, boost mid tones, and adjust colour balance. All in one tool. So no more having to use the brightness/contrast controls, level controls and colour balance to tweek your image. Sounds complicated. But there is a very easy way to use curves to correct photos. Starting image. It's OK, but the colours are a little flat and washed out. My aim is to boost the contrast without making the colours stand out too much. Open the curves tool (I prefer to use a new adjustment layer for this so I can re-adjust the image if I'm not happy, Layer/ New Adjustment layer/ Curves) and select the right hand eye dropper. Now click this eye dropper on the lightest part of the image, I used the chain fence in the bottom right of the picture. Now click the left hand eyedropper, and select a dark area of the image. I picked under the bridge. You will notice very subtle changes in the curve lines on the graph. I say lines because there are now more than one, representing Red, Green, and Blue tones of the picture. The picture now has better contrast and looks more alive. I am not happy with the green though. I think it is a little over bearing, making the picture a bit too vibrant. No problem, i can fix this with curves as well. Click on the RGB tab and select Green from the menu, You can now adjust the properties of just the green channels. Click the middle of the curve line and drag it everso slightly over to the bottom right corner, this will make the vibrant greens a tiny bit darker and less dominating. The brick work on the bridge now stands out more and feels more natural. Once you get the hang of it you'll wonder why Adobe even bothered with the brightness/contrast control.
Brilliant! And thank you. You're right - all I ever did was pull the curve about, usually to lighten up the photo a bit, but using the pens and the colour channels makes a huge difference. I'm still using PS7 and don't have the histogram-type thing on mine, but the droppers and colour channels work the same. I'm away now to play with some more of my photos and to see if it works as well with B&W. Hope you do some more tutorials - you're a great teacher. It's so much better to be shown something in a few simple steps, than having to take the Photoshop Bible to bed with me ....... (sad git!) Masks would be nice, too, when you've got a bit of time to spare </hint>
Thanks for the comments, glad I am able to help someone. Masks have a huge range of applications. If you let me know what type of thing you want to do with them It will be easier to write something for your needs.
As an example, in the photo I've posted in this thread, http://www.clubgti.com/forum/showthread.php?t=172483 I'd like to alter the colour of the blanket, as I think it detracts from the colour of the cat. But how to mask that? I tried a 30-day version of Fluid Mask, which advertised it could mask hair, smoke and stuff like that. But only if it was against a very plain background, it seems. Or am I asking the impossible in a photo like this one?
Changing background colours around hair whilst retaining the hair colour is not easy if you want to keep the photo looking natural. In this pic I would suggest toning down the colour of the blanket. Using multiple layers and masks is a good way to achieve this. Open the original image and make a duplicate layer of it. (Ctrl+J) Making sure this new top layer is selected, use Image / Adjustments / Hue/Saturation to reduce the colour saturation of the pic. It doesn't matter if you reduce it to much at this stage as this can be rectified later. Now apply a layer mask to this layer by clicking the icon on the bottom of the layers pallet. Select a medium sized round brush and set the hardness to 0 to give a soft feathered edge, select black as your foreground colour, and paint directly onto the layer mask, the bottom layer will show through with its original colours intact. As you get to the edges, reduce the opacity of the brush to around 25% to go over the areas where hair and blanket meet. If you think you have revealed too much red beneath the hair, switch the brush colour to white and go over the area again. If you feel the blanket is now a little too dull, in the layers pallet, select the top layer (not the mask) and reduce the opacity a little. Here I also included the wall in my layer mask so only the blanket was toned down. Hope that helps.
Practically every time I've chopped something for the last 2 years or so I've used curves, one of my most utilised tools.
