I agree what Alex said.
I'm not a matte painter, but I do some images and been hanging around here for a while. If I don't remember wrong, you did have some earlier arts experience, so that is good. If you were looking for the actual "making of" or how to approach a piece or to get started, there are abundance of choices. YouTube, dvd extras and maybe those gnomon dvds about mattepainting could be good sources.
Process depends on the person making the image (if personal preference of methods are allowed in working), task at hand (for example replacing sky is different task than making large, imaginary scenery with complicated camera move) and other possible directions/limitations by client or someone else.
The guidelines for process are to make it easy (fast and cheap), looking good (or what ever it should look), satisfying for yourself and meet the other expectations of the client.
But if just making a beautiful image for your self or for someone else from scratch the process might (or might not) include these steps in some order depending on the need:
[making the idea clear]
- Reading the brief / making the idea clear
- Sketching for suitable composition and preliminary color scheme (maybe in thumbnail size)
- Gathering or taking the images and preferences that inspire you and may be used as a reference, textures or something else.
- Some prefer working in double size compared to final output. It leaves a little more moving space and lets you work slightly more loosely and paint details easier, since they kind of come together when reduced to final size. So making a double size sketch, painting at the base of everything - or picking a plate image to start with if some of your references is close enough and painting the parts you want to replace or add or remove.
- Preparing the images for working. This might include for example cleaning them from everything not wanted, matching the colors and black levels, removing the noise, and bringing them to the right working colors space. This part just tries to make sure that images you use, might exist in the same universe. ;-)
- Using the images when possible to get what is wanted. Taking part from here, another from there. Some may serve as textures, some may do well as they are, some may add just details and patches and some may contribute just right kind of light or color. If you can't find the right kind of image there might be possibility to take one, model something with 3d or miniatures, paint the parts needed or something. Try to keep with the original idea so that missing of a "right" photo doesn't ruin your work.
- repeat until fine
- finalize the image for output, mainly providing the image as it was asked, but if making for your self then maybe adding the noise (now the same for all the images), final levels and color corrections, lens effects etc if wanted, using the right sizes and color spaces for print or whatever you do.
Some time ago Alenah posted her process with images here:
Suirebit also made tutorial about simple set extencion here: http://www.tiberius-viris.com/tut1.html
. There might be something else too, but can't remember now.
I've also made couple of gif-animations about how images are constructed. Animations show layers stacking in order about 4 frames/layers in second. One frame may skip sometimes quite a lot of work, like arranging a photo shoot or painting a lot. I'll just link em, since they are quite large - from 1.5mb to 5mb and not actually a subject of this post. Check if interested:
This one is closest to the process I described: Draw near to my soul
Last two are in black and white so playing with color is not important here, but the luminosity increases in importance.
This one was quite simple: The Eminent Storm
And this ones biggest task was to get luminosity as wanted. Idea was simple so no sketching here (but actually made 6 variations before getting to this): Storm
. Original image of Cliffs of Moher by Jaana Hartikainen.
I know those images are not actually matte paintings and they have many issues (that's why not posted here), but they show a one process of how an image is constructed with mixed techniques and as mentioned, it might change totally depending on the task at hand.
Hope this helps a little. If you have any more specific question it would be easier to answer. Meanwhile it's just sketching it, putting it together and a lot of work until it looks good.