Document Trapping

Question 0

Amount of ink printing on top of another ink

Answer 0

Ink trapping

Question 1

What is trapping

Answer 1

2 kinds: object & ink trapping

Question 2

Vector and raster objects that overlap

Answer 2

Object trapping

Question 3

The four trapping instances

Answer 3

1. Overprint
2. Knock out
3. Keep back
4. Spread or choke

Question 4

Transparent colour are also known as

Answer 4

Process colours

Question 5

Overprint occurs when…?

Answer 5

One colour prints on top of another colour

Question 6

Overprinting is used because

Answer 6

Overprinting is used to create different colours

E.g. Printing yellow over magenta = red

Question 7

Black almost always overprints other colours (especially when dealing with small black type): T or F

Answer 7

True

Question 8

Does black overprint when an opaque ink is being printed overtop black?

Answer 8

No, an opaque ink is the exception to the rule that black overprints other colours

Question 9

How to prevent overprint on large black type?

Answer 9

Treat large black text as an object

Question 10

Knock out is when:

Answer 10

1. An object removes all the image below it creating only that object printing in that space.
2. Only occurs when using 1 colour
   (E.g. If yellow must stay yellow, we must remove magenta from behind it)

Question 11

Opposite of overprinting is:

Answer 11

Knock out

Question 12

Keep back is

Answer 12

Knocking out the chromatic (non-black) inks around reverse text and images and edges in rich black situations

Question 13

Spread occurs when

Answer 13

The expansion of a lighter colour into a darker colour to compensate for press misregistration

Question 14

What makes slight misregistration less noticeable?

Answer 14

Slight overlap

Question 15

Choke occurs when

Answer 15

Lighter colours contracts into darker colour b/c of press misregistration

Question 16

What involves distorting the shape of an object? (I.e. Making it fatter or thinner)

Answer 16

Spreads & Chokes

Question 17

To minimize the negative affect of distortion, always…?

Answer 17

Distort the lighter colour

Question 18

Lightness is defined by…?

Answer 18

Neutral density (value as it would appear as a greyscale measured with densitometer) using visual filter

Question 19

What is a visual filter?

Answer 19

Filter for K

Question 20

When not to trap

Answer 20

1. Seperate colours - colours don’t touch one another

2. Common colours - foreground & background objects share one or more colours

Question 21

Trap inks not colours : T or F

Answer 21

TRUE

Question 22

What part of raster images need trapping

Answer 22

Often the outside edges only need trapping

Question 23

Images commonly too complex to trap and really don’t need trapping are also known as…?

Answer 23

Raster images

Question 24

Double trapping usually occurs when

Answer 24

Trapping by hand

Question 25

Traps are usually applied if file in printed as separations

Answer 25

Application based trapping

Question 26

Concerns of application based trapping

Answer 26

Can’t trap placed objects

Settings may change during output

Question 27

How is trapping done in RIP

Answer 27

Traps are applied to composite files that have no previous trapping applied

Question 28

PDF/ x-1a files have to include a tag trapped : yes or no

Answer 28

No

Question 29

Neutral density is also known as….

Answer 29

Lightness