GRC 328 FINAL

When print tacky inks on cast coated paper with low basis weight, which blanket is more likely to cause picking problem?

Conventional blanket with high smoothness

Which of the following statement about blanket is NOT true?

Conventional blanket with low smoothness is good for high resolution printing

Based on the previous question and image, if the dark area (letter A) is exposed, what type of film is used for plate exposure?

Negative

This is an offset plate, if the photopolymer on the image area is hardened upon exposure, what type of plate is it?

Negative

This is an offset plate. If the photopolymer on the image area is hardened upon exposure, what type of plate is it?

Negative

This is an offset plate, if the blue area is exposed, what type of film is used for plate exposure?

Negative film

Which of the following substrate has the largest dot gain when printed at same density?

Newsprint

This is a offset plate, which part is non-image area on the plate?

The grey area.

This is an offset plate, which part is non-image area on the plate?

The light green area around letter A

Which of the following picture shows an external drum plate setter?

The right one

The picture shows two types of gray, how is it used for checking print quality?

To check gray balance

Why is black ink used in printing?

To improve gray balance by printing black. To reduce cost of printing less color inks. To improve details in shadow areas.

During the finishing process, what is the purpose of applying gum Arabic to the plate?

To prevent the non-image area from being oxidized.

Which of the following is NOT one of the 3 cylinders in a three-cylinder system in a sheet-fed offset press?

Transferring Cylinder

AM screen uses different sizes of dots to reproduce light to dark. Smaller dots are for lighter areas, bigger dots are for darker areas.

True

Colors communication requires numerical expressions instead of descriptive language that can be ambiguous.

True

Higher screen ruling will creates higher dot gain.

True

Human eyes are most sensitive tools for perceiving colors but it can be fooled by optical illusions.

True

Offset printing uses half-tone dots to reproduce continuous tone image. When dots are small and close enough, our brain takes shortcuts to perceive them as continues tone image.

True

Pantone books are physical color guide for designers and printers to communicate colors accurately.

True

Grained aluminum surface on the offset plate base is to

improve its ability of accepting water

On the offset press, the bearers of the plate cylinder ___________

is level zero when measure the cylinder packing

Ink stripes method is used for checking ________________

roller pressure at the nip

At drying section of the press, spray powder can help to avoid .

setoff on the backside of sheets

Printing speed of sheet-fed offset press is web offset press

slower than

What is the cause of the blanket condition showed in this picture?

sprayed drying powder

Screen ruling affects ___________

dot gain

Based on question 6-8, if the proper packing of this press is 0.001", what would be possible consequences (for the plate, blanket, print quality) under the current packing pressure? Choose ALL that apply.

excessive dot gain premature wearing of blanket and plate

Under the print sequence of KMCY, which color will have highest trapping?

red

Which of the following statement about feeder is NOT true?

For stream feeder, sheet travels the same speed as press

Based on the results from Question # 12 and 13, what is the total squeeze of the plate and blanket cylinder?

0

A color swatch has such CMY values: C 40%, M 70%, Y 80%, if GCR is applied, what is the CMYK percentages?

0, 30%, 40%, 40%

Based on the question 6 and 7, what is the total squeeze of plate and blanket cylinder?

0.002

Blanket cylinder has undercut of 0.081", blanket has thickness of 0.077". The total thickness of packing sheets are 0.006". The blanket packing is ______.

0.002

Plate cylinder has undercut of 0.001, plate thickness is 0.003". How much is the plate packing height?

0.002

Followed by the previous question, the plate thickness is 0.003". The undercut of plate cylinder is 0.006". What is the packing height of this plate cylinder?

-0.003

On the same print unit as in the previous question, the plate thickness is 0.002". The undercut of plate cylinder is 0.005". What is the packing height of this plate cylinder?

-0.003

Which arrow is pointing at the impression cylinder?

#2

For question #12-13, please type in answer as number without unit. Type the number with the 0 before the decimal, such as 0.001, not .001 Blanket thickness is 0.006". Two pieces of packing sheets are used. Each packing sheet is 0.003". Blanket cylinder's undercut is 0.009". what is the packing height of this blanket cylinder?

0.003

Based on the previous two questions, the total packing height of plate and blanket cylinders of this press is _____________.

0.004

Blanket thickness is 0.008". Two pieces of packing sheets are used, each packing sheet is 0.002". Blanket cylinder's undercut is 0.007". What is the packing height of this blanket cylinder?

0.005

The chart below shows the dot gain curve of an offset press when printing on gloss coated paper, at the speed of 6,000 sheets/hour, under 350 psi pressure. How much DOT GAIN will occur for 50% dots under such printing conditions?

15%

Follow question #9-10, if you are provided with enough packing sheets with the thickness of 0.005" per piece, in order to adjust the packing condition (assume the plate and blanket thickness stays the same). How many pieces of such packing sheets are needed, in order to achieve the ideal packing?

2

Which number correctly describes the undercut in the picture below?

2

Which of the following paper is not appropriate for aqueous coating?

27 lbs text

This is the dot gain curve for GTO offset Press under such printing setting: substrate: gloss coated print speed of 8,000 impressions per hour (sheets per hour), print pressure 350psi. According to the chart, how much DOT GAIN will occur for 60% dots under such printing conditions?

28%

If you want to adjust the current packing to ideal situation, assume you have enough pieces of packing sheets with thickness of 0.003" per piece. How many pieces of packing sheets are needed to achieve the ideal packing?

3

Which number indicates the undercut of plate cylinder _______

3

Which of the following statement about aqueous coating is true?

Aqueous coating works better on coated paper than uncoated paper.

Follow the previous question. If you want to print exact 60% dot on paper under such printing conditions, how to compensate the dot gain while making the digital files during prepress?

32%

On a press sheet, if the density value of different tints are measured as following, what is the print contrast of this print?

33%

Main dot gain area of halftone printing is __________

40-60%

On an offset press sheet, 100% solid cyan has a density reading of 1.6. The 50% tint density is 0.6, the 75% tint density is 0.8. What is the print contrast of this sheet?

50%

At printing speed of 10,000 prints per hour, 50% dot on plate appears 65% on paper. Which of the following number is most likely to be the dot percentage on paper when print faster? (Assume all the printing conditions are the same except the speed)

60%

How many transfer drums are there in this picture?

7

What is the acceptable Delta E value for proofing?

<2

The image shows a 4-color book cover, the book title is applied with glossy UV coating. Which press configuration is NOT possible to print this job within one pass?

A four-unit press

What is the function of double sheet detector?

Avoid blanket cylinder being damaged

Which of the following statement about this print is true?

B is the gripper side.

Which of the following statement is true?

Backtrapping is caused by excessive pressure between coating blanket and anilox roll.

How is the coating thickness adjusted on a tower coater?

By adjusting the roller speed and gap between roller and blanket.

After being exposed, how is the processless plate being developed?

By contacting dampening solution on press or water rinse.

Ideal gray on digital display is the mixture of equal amount of CMY. But in reality, to reproduce more realistic gray during printing, what should be the percentage of CMY?

C 50% M 40% Y 40%

A color is designed as such combination of inks: C 50%, M 10%, Y 30%. If GCR is applied during color separation, how much CMYK will be used to reproduce this color?

C40%, M0%, Y20%, K10%

Which one of the following statements about offset plate graining is NOT true?

Coarsely grained plate is good for reproducing image with high resolution.

Which of the following statement about the roughness of offset plate base (aluminum) is correct?

Coarser plate is capable of holding more water

If a negative film is used for the plate exposure, what type of plate is it?

Contact plate

________________ is suitable for printing on texturized paper with good solid density.

Conventional blanket

Excessive blanket packing can cause ____________

Excessive dot gain premature blanket wear Premature plate wear

Backtrapping refers to the problem while black ink transfers onto the blanket in yellow unit.

False

Chemical ghosting appears on the same side of one press sheet.

False

Compressible blanket is good for the card shown in this picture.

False

Pantone swatch books are suitable to serve as color guide for all types of printing processes with any choice of inks and substrates.

False

Polyester based plate can be used for high quality offset printing.

False

Positive and negative working plates use the same type of photopolymer which have the same reaction upon light exposure.

False

Shadow area (75% - 100%) is the main dot gain area because it has most ink coverage.

False

The picture shows a book cover printed with 4 process colors +spot UV coating applied on the book title "SUNRISE HITEK". This job can be done on a 4-unit offset press within one pass.

False

Visible light spectrum range is 380-480 nm. it's only a small portion in all wavelengths of light.

False

When print 50% dots for a logo, printing at solid ink density of 1.5 makes the logo look darker than printing at solid ink density of 1.7. (Assume 50% dots have no dot gain for both printing.)

False

Which of the following statement about offset plate is correct?

Finely grained plate with lower roughness produce image with high resolution.

A color is designed to be printed by such combination of inks: C 50%, M 10%, Y 30%. During the color separation, which process is the more cost effective to reproduce this color?

GCR

A color swatch has such CMY values: C 40%, M 70%, Y 80%. You are going to choose UCR and GCR to process this color for printing. Which process is the more cost effective?

GCR.

If you are tasked to output personalized invitations for a local fitness club, that will be sent to all its 1,000 members, what printing process would be the worst choice in terms of cost-effectiveness?

Gravure

On a sheet-fed offset press, the print sequence is K, C, M, Y. Which overprint color will have the best trapping?

Green

Which of the following statement about trapping is NOT true?

Green always has the best trapping for offset printing.

During a 2-sided, 4-color offset job, after the side A is printed, there is set-off ink on the back side (unprinted side) of sheets, which of the following would help to alleviate this problem? Choose all that apply.

IR dryer hot air spray drying powder

Which of the following statement about mis-feeding is NOT true?

If crooked sheet is detected, the feeding action will stop.

Which of the following statement about offset is NOT correct?

Image and non-image areas have the same property of accepting water

For processless plates, which which area get exposed?

Image area

While expose the processless plate, which area is exposed?

Image area

Black is used in printing to ____________. Choose ALL that apply.

Improve density Reduce cost of color ink Improve details of shadow area

Which one of the following statement about coating unit is NOT true?

In order to achieve good adhesion, coating unit has higher pressure than printing unit.

Which of the following statement about ink density is NOT true?

Ink density has no correlation with ink film thickness

Which of the following statements about "in-line finishing" is true? Choose ALL that apply.

It has faster turnaround compared to offline finishing It includes inline perforating, embossing, scoring and varnishing. It offers better quality control with less labor cost

A color swatch has such CMY values: C 40%, M 70%, Y 80%, if UCR is applied with 15% of black, what are K, C, M, Y value after this process?

K15, C25, M55, Y65

Which of the following L*a*b* values represents a neutral color?

L*= 78, a*=1, b*= -2

How is the dot gain compensated during the prepress?

Make the file with lower dot coverage (tint) according to the dot gain curve

The text in the blue background are the ghost images. What type of ghosting is this?

Mechanical ghosting

Which of the following statement is true?

Mechanical ghosting is caused by ink rollers didn't re-pick up enough ink.

After a processless (CTP) plate is exposed, what areas on the plate are removed during the developing process?

Non-image areas.

Which surface finish process will yellow over time?

Oil-based varnish

Pantone swatch books are not suitable for all types of printing processes. Why?

Pantone swatch book cannot match colors printed on different substrates other than the exact substrate it is printed on.

Which of the following statement about print contrast is NOT true?

Print contrast tells how well the midtone details are reproduced

To minimize problem in the previous question, which of the following approach is the best solution?

Print on the press with four form rollers instead one.

Which one of the following statement about gray balance is NOT true?

Realistic gray for offset print can be achieved by mixing C 50%, M 50% and Y 50%

Which of the following statement about registration is NOT true?

Registration is achieved by one front stop and two side guides

Which of the following can be used to measure the roller pressure on press?

Roller pressure indicator

Following the previous question, which side will be more likely to have mis-registration on the offset press?

Side A

The picture shows the printed papers by a sheet-fed press. Which side the gripper side?

Side B

Non image area of a waterless plate is on

Silicone rubber

Which one of the following statement is NOT true?

Slurring and doubling are causes for dot gain.

Which of the following statement about slurring is NOT true?

Slurring is caused by the blanket is under-packed or form rollers pressure too low.

Which of the following statement is NOT true?

Smooth blanket printing on cast coated paper will have good solid density.

Perceptual non-uniform means human eyes have different tolerance and sensitivity to different colors in the visible spectrum: they are most sensitive to blue, and lease sensitive to green.

True

Scumming is a printing problem that can be corrected by adding more water on plate.

True

Scumming on offset prints can be fixed by applying more water on the plate.

True

Slurring may appear when printing on cast coated paper with smooth blanket.

True

The colorimetric tools and CIE Lab color system meet the need of communicating colors with precise numeric expressions.

True

The contact line between ink form roller and the plate cylinder is a nip.

True

The ellipses in this graph represent the color discrimination threshold of human eyes across different colors in the spectrum.

True

To check if the colors on press sheet are matching with the original design, the Delta E76 should be less than 5.

True

If a package is printed with spot color that requires high gloss finish, what is the best coating option for it?

UV coating

In CIEL*a*b* color system, a neutral color

a* and b* values are close to zero

When packing blanket cylinder, packing gauge is zeroed on _______

bearer

Which of the following is NOT additive color?

black

If the double sheet detector failed, it can cause _________

blanket damage

Aqueous coating and varnish will have better results if it is applied on

coated paper

This is an offset plate. If the non-image area dissolves upon light exposure, what type is this plate?

contact plate

When expose a plate with film, such plate is called ______________

contact plate

Which printing process needs to control two fluids on the plate simultaneously?

conventional offset

Which of the following will cause OPTICAL dot gain? Choose ALL that apply.

laminations clear coating or varnish

What are possible causes for optical dot gain?

laminations varnish clear coating

The graphs show the pH values measured on 2 offset press. Which one is more likely to produce high quality prints?

left one

Spectrophotometer is a color metric tool that _____________

measures multiple specifications used for printing quality control

Which unit are used to describe FM screen?

micron

After the processless plate is exposed, which area is removed in the developing process?

non-image

Scumming happens on

non-image area

Which coating option may yellow overtime?

oil-based varnish

A spectrophotometer measures

physical dot gain optical dot gain

Three cylinders that are common to all sheet-fed offset presses are

plate, impression, and blanket

The print quality of a press sheet is determined by ___________. Choose ALL that apply.

prepress software inks and substrates of choice conditions such as printing pressure, speed during production

If the early or late sheet detector failed, it will result in _____________

print on impression cylinder

Which of the following factors reversely affect dot gain ? (meaning the dot gain decreases when the factor increases).

printing speed

A color is designed as such combination of inks: C 70%, M 60%, Y 50%. If neither GCR nor UCR is applied during the color separation, which of the following will be likely to happen during the offset printing? Choose ALL that apply.

the image contrast between shadow and highlight area is poor the detail of shadow area is lost the CMY ink consumption is high the ink drying is prolonged

After litho plate is exposed and developed, a layer of gum is placed on the surface of plate. The purpose of doing this is

to prevent the non-image areas to be oxidized

Each sheet fed to the press is aligned at feeder. It is aligned by .

two front guides and one side guide

Based on question #7-9, if the ideal total packing height between plate and blanket cylinder is 0.008", the current packing condition is ______________

underpacked

Based on the results from Question #12-14. If the ideal total packing height of this press is 0.003", based on the results of the current total packing you calculated from Question #14, it is _________.

underpacked

Compare the ideal packing and the current packing, what consequences could be expected on this press?

wash-out prints with low density

For a print job, the stock size is 19"X25", trim size is 18"X22", which sheet reversal option is better?

work and turn

How to describe the resolution of FM screen?

µm