MacroSystem Bluebox World User Manual

Page 26

8.3 Select and adjust Bluebox effect

A Bluebox World effect is set up in a number of

stages. The foreground object, or motif, is first

isolated through the use of a suitable Bluebox

effect. Corrections and fine adjustments are

then carried out, after which it is possible to add

special effects.

8.3-1 Selecting the Bluebox mode.
Selecting the correct Bluebox mode, (in other

words the Bluebox process that is employed),

is of particular significance. Not every object

is equally well suited to Bluebox technology,

and a careful analysis of the foreground

scene is necessary in order to determine the

correct technique. It is best to begin with the

“Standard“ mode, and then compare the results

with the results of other special modes if the

initial result is not satisfactory.

Because, in our example, the foreground scene

makes use of a basic color (blue), we have

chosen the “Bluescreen“ mode. First of all,

therefore, the “Bluebox Mode“ must be changed

in the left-hand function bar from “Standard“

to “Bluescreen“.

8.3-2 Make settings for the“Bluescreen“ Bluebox

mode
A total of three settings can be made in the

“Bluescreen“ mode. It is important that their

values are set accurately, although the fine

adjustment should not be overdone. This

is because Bluebox World offers additional

powerful tools to correct faults that may occur in

the image and to achieve realistic results.

• Mode

This is where you specify the color of the

foreground scene that will later be made

transparent or, so to speak, “invisible“. This

requires the color of the background to be set,

which in this case is “Blue Screen“. After this

you should already see the other scene in the

background instead of the blue area.

• Tolerance

You have now selected the basic color that

will later be made transparent. We must now

recognize, however, that the “wall“ is often not

entirely of a single color. The results are always

going to be better when the color of the wall is

more even, but even the best arrangement will

have a certain degree of variation, if only the

camera noise.

It is therefore necessary to compensate

for these variations. This is the purpose of

the“Tolerance“ slider. This sets the tolerance

that will be applied when evaluating the mas-

king color. A low tolerance value therefore calls

for a perfect “wall“. If the tolerance is too low,

or if the Bluebox wall is not clean, perhaps be-

cause shadows are falling on it, then “flecks“

of wall will remain visible.

Experience shows that good results are

obtained under correspondingly good initial

conditions from the “Bluescreen“ mode when

the tolerance is around 50%.

• Matte density

This slider allows for compensation of diffe-

rences in brightness in the background caused

by uneven illumination of the background, dark

image edges or by shadows. The effect of this

regulator is usually most often seen at the outer

edges of the person, where the illumination is

often poor. Beginning from an initial setting of

0%, move the slider upwards until on the one

hand residues of the blue background are no

longer visible, while on the other hand avoiding

transparency of the foreground object.

You see the result of all these changes in

settings immediately on the screen.