Blue/green screen vs matte painting

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michiel
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Joined: May 13 1999

About a year ago I came across an article on an American web site, that seems to have subsequently closed, it said that for creating high quality effects on a small (nil) budget we should be looking towards using matte painting and not the “all singing all dancing” blue/green screen technique. The reasoning was that to get b/g screen to look realistic requires expensive Adobe plug ins i.e. Ultimatte The less “sexy” technique of matte painting is still widely used and apparently quite easy using modern computers and software that we may already have, Adobe Premiere,Photoshop,AfterEffects.
Perhaps the more worldly wise could post there comments and maybe outline the procedures and pros and cons of both techniques.
In closing can I say that with addition of this new forum we are quickly moving towards the all encompassing site on the art of visual entertainment / education production.

bcrabtree
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Joined: Mar 7 1999

I don't know the answer, but I *DO* like the sound of what you say!

Bob C

RichardJ
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Joined: May 7 1999

michiel

I'd just like to clarify what you mean here. When you say "matte painting", do you mean using a computer graphics tool to create a matte mask that exactly registers with the video subject - frame-by-frame?

If so, VideoPaint with MediaStudio Pro can be used effectively to do this. The technique's covered in my tutorial (out by the end of this week - www.activeservice.co.uk ).

If that's not what you mean, can you clarify please?

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Richard Jones

Richard Jones, http://www.activeservice.co.uk
Home of the MediaStudio Pro Tutorial - Edition 3 for MSP 7

michiel
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Joined: May 13 1999

Richard

I agree the above was a bit vague, it was posted so that I may be enlightend and not visa versa, Being a newish convert from "The Bootlace" I can say that the effect can be very effective.
I have now found the printed copy of said article and got it back into digital form and post it for your information.
The article was posted cica. Prem 4.2 AfterEff`s 3.0 PhotoSh`p 4.0

"Matte Paintings
Why is Photoshop so important for digital filmmakers? The answer is matte
paintings.
Matte paintings are still images which have been combined with a motion
picture. These are done to extend, enhance, and expand your motion picture
sets.., especially for establishing shots.

Background
In the past, matte painting were created by painting realistic images on
glass leaving part of the glass clear so that the live action can be seen
through the glass.
With digital imaging, matte paintings can be almost any still image from
stock photos of scenery to 3D renderings from a 3D animation program.
Obviously, one important use of Adobe Photoshop is for creating the black
blob which acts as the mask. But there is a far greater use ofPhotoshop
which is not evident. Even though the matte painting is supposed to smoothly
blend between the still image and the live action, this is rarely the case.
With Photoshop, you can modify the painting so it has the same look
and feel as the live action movie set.
As an example, I created a matte painting using Virtus WalkThrough which is
a very simple 3D virtual reality program for visualizing building before
they are built. The texturing features of the program are very limited and
the lighting controls are extremely basic with no spot lights, no shadows,
and only directional lighting. This is no problem with Photoshop.
To create the matte painting for my movie, I simply took the textures from
the live action movie to modify the matte painting until it matched
perfectly. Once you have mastered Photoshop (about one year)

Creating a Matte Painting
I. To use a matte painting, you build a tiny movie set which is only as big
as where the actors will move during the scene.
2. Lock the camera down so it cannot move.
3. Film the scene.
4. Export the beginning and ending frame of the scene to a still image in
Adobe Photoshop.
5. Create your a matte painting using a photograph, 3D model, fractal
scenery, painting, etc.
6. Take both a still image from the movie and the matte painting and put
them on separate layers in a single file in Photoshop. Initially, to see
both layers, temporarily set the transparency of the top layer to 50%. As
soon as you create the mask, turn the transparency to 100% opaque.
7. It is easier to have the matte painting on the top layer. Then use a
”layer mask” to create a hole in the matte painting so you can see the frame
from the movie in the hole. You can use this mask in Adobe Premiere or Adobe
AfterEffects when you composite the movie.., but I prefer not to. (see
below.) But for now, create the mask... even if you will not use it later.
8. Once you have the mask roughed out, you can see two images combined as
one. Now comes the fun (hard?) part. You must adjust the matte painting so
that it has the same shading and the same brightness and the same texture as
the movie set. If you have worked with levels at all in Photoshop, you will
know how to change the brightness and the shading quickly.
9. If the textures of the two images do not match, change the texture of the
matte painting around the hole by copying the texture from the movie set and
blending it onto the matte painting. Again, this is no problem if you have
worked with Photoshop.
10. Once the matte painting is perfect and you cannot see any difference
between where the matte painting ends and the movie starts, test the matte
painting with the last frame of the movie. Usually, you will see some subtle
changes that need to be made to the mask or the matte painting. When this is
done, you are finished with the matte painting.
1 I. “Flatten” the matte painting and save it as a PICT image on the
Macintosh with an alpha channel for the hole. (Sorry, I am not sure what
image is required on a Windows PC.)
12. Now you can bring the matte painting into Adobe Premiere (or any editing
program which does compositing). I actually prefer Adobe AfterEffects
because you can create a mask with the pen tool and have the mask change
throughout the movie clip. This is a lot more flexible and blends better
than a single alpha channel mask.

Blue Screen Vs. Matte Painting
In contrast, if you want to use a blue screen, you must somehow select the
blue background without selecting anything which has blue in it. This must
be done for every frame of the movie.
This assumes that you put a blue screen up where you were filming. At times
this can be very difficult.
This is easy with Ultimatte’s plug in for Adobe Premiere but this costs
$1,500.

Matte paintings can be very tiny areas of the scene which are used to hide
something which is ugly. You cannot do this with blue screen.
Or matte paintings can be tiny areas of the movie set which need
improvement.., such as changing the name of a street sign or store front.
For establishing shots, matte paintings can be huge and the movie set very
tiny.
This is why Matte Paintings are more flexible than blue screen.
Currently blue screen work is considered very high-tech. Every filmmaker
dreams of having at least one blue screen shot in their movie.
This is wrong!
Digital filmmakers who have access to the power of Adobe Photoshop should
never use blue screen when they can use a matte painting. Matte paintings
are more realistic, easier to do, and can cost a considerable amount less.
Most blue screen filters are not very good and make the image look
unrealistic. The Ultimatte plug-in for Photoshop is the best blue screen
tool on the market but it costs twice as much as Adobe Premiere. Go to their
web site and test their demo version with their sample images. Adobe
AfterEffects production bundle cannot do these images correctly.
Matte paintings have been around so long and have been used so frequently
that most people do not notice. Almost every effects picture has some matte
paintings. Every issue of Cinefex has pictures of matte paintings.
It is just that matte paintings do not get the publicity that blue screen
does. So... don’t do blue screen, do matte paintings instead"

The writer as I recall was involved in producing feature lenght movies for "Direct to DVD/Video" release in th US.

Hope this helps and informs in some way.

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Christian Lett
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Joined: Apr 26 1999

So how do I do the following shot for my next video?

GIRL putting make-up on looking in mirror. MYSTERY MAN walks round her but does not appear in mirror.

We're planning on using a blue/green screen, reflected in the mirror and then erasing the MYSTERY MAN character from the reflection. A second shot will be from the same angle but with no blue/green screen and no subjects (ie. just the reflected background). With a bit of care when setting up and some good lighting, this should work (I hope ).

If anyone else knows how, I'd appreciate the advice.

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Christian J. Lett
[email=clett@nationalexpress.co.uk]clett@nationalexpress.co.uk[/email]

Christian Lett After Effects and Maya Artist www.quarterlightpictures.com

michiel
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Joined: May 13 1999

To start the ball rolling on this and working on the “K.I.S.S.” principle, two ideas come to mind

First : with careful positioning of actors/mirror/camera the inference of the illusion can be created as an example watch the similar set up in “Fallen Angel”.

Second : Shoot scene with girl only, (with camera locked)shoot take 2 with both ,important that she can reproduce head movements etc or on take 2 obscure back of her head with his body? Whatever and just show reflection. The reflection part of take 1 is used as matte over the reflection in take 2 The edges of the matte should be easier to blend in around the edge of the mirror frame. I would suggest easier and cheaper than trying to get good result around hair lines when using blue/green screen.

That`s my two peneth worth.
Hope to see the finished product (at the new C.V. Awards????) soon

michiel

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