Prepress quality steps (2)…..

16- We made a separated films for each color (CYMk) .we should make some tests on films like measure the film density by using Densitometer (which the standerd measure for solid black area should give density value typically 3.8, and 4.0 D)

17- Also we measure some tint in film like10%, 50% , 80% & 100%% for films using Densitometer to avoid Dot Gain in films.

18- In case we use films to make plate we should select the right expose by using tools like Ugra test to measure the right expose & right developing time (Good Developing time + right Expose = right plates)

19- If we send to CTP plate directly, we should calibrate the plate exposed first & check the accuracy of chemicals by using the digital files for calibration which sent with the CTP plate machine.

20- Now we have exposed plate from CTP or Conventional we have to check in this plate before we send to printing machine. So we use plate reader to check on the screens & fine line & text ,also we check on if there were any wrong assign in non-printing areas using corrector pen ,all this checks to prepare plate to be ready for printing .

21- Now we have a ready for print plates ,SO it is time to gumming this plate , in this step we have to use the suitable Gum for gumming operation . because the wrong Gum will effect badly on plates Emulsion & could damage it .So for thermal plate we should use in first gumming operation we use thermal Gum only to save plate . for Ctp plate we use synthetic Gum for gumming but in conventional plate we use Arabic Gum.

22- The majored point also help to save quality for plates Is the right chemicals developing & Dosage which suitable for plates.

23- Now the plate is ready to send to offset machine to print we have to save the exposed plate in save place & avoid any light or heat effect .
Next Article we will discuss about some difference between technology & recommendation when dealing for each one .

Quality assurance is the major point we will discuss in this articles. Beginning with artwork we should follow some recommendation & check in some point as the following:

1- We should calibrate the tools we use in prepress we mean to calibrate monitors by using monitor calibration tools like ( I1 instrument ) for example , calibrate printer & scanner by using (IT 8 ),calibration screen by using monitor calibration tools . This is the most important to keep the right color in prepress like the final result ,also it helps to make ( ICC profile ) for our instruments to achieve the quality .

2- Depending in our design in Panton color value not use visual to select colors.

3- Review each picture we use in design & make sure the resolution of it (should be 300 pixel / inch.

4- all text should assign in one color specially the small fonts to be sharp after printing .

5- We check in the number of color in artwork & replace any pantone color or other additive color .

6- Check in the right skim for imposition and the number of pages ,
7- We should check in the number of each Bounding book.
8- All fonts include the file we prepare or change the text into close text in order not to change after sending to color separation.
9- If the work is boxes, we should make 0.5 from each side from boxes to avoided cutting text after box cutting.

10- We should remove any color from box flab to avoided bad flap adhesion after in folding step in boxes.

11- Numbering: that mean add number for each box, to make it easy to figure out any problem in boxes during printing.

12- We should test the di-cutting for boxes to avoid any problems after cutting & creasing.

13- Now we finish the box artwork, we have to assign in each imposition the suitable margin for each plate & each printing machine we prepared the file for it .

14- Also not to forget to put the color strips, color bar & register marks.

15- Now we are ready to Send files to separation, we should send it as the right format like( PDF,TIFF .JDF,EPS,CIP3,CIP4 .…etc ) which is suitable format for workflow we use (Kodak , prinect , Esko ,…etc ) we deal with .

……………………………………………..The article will be continue in next Article .