M R410 e [PDF]

Zitiervorschau

Manual Color densitometer R 410 and R 410e

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TECHKON ManualWelcome

Welcome

TECHKON manuals, technical documentation and programs are copyrighted. Reproduction, translation or transfer to an electronic medium - in whole or in parts - is prohibited.

Welcome

Accompanying TECHKON software is the intellectual property of TECHKON GmbH. Purchase of the software grants the user a license for use on only one computer. Programs can only be copied for back-up purposes. TECHKON can not be held liable for any damages that may occur through use of the software.

Welcome to the circle of TECHKON users. We are glad that you have chosen to purchase a TECHKON Color Densitometer R 410/e. With this manual we want to present you an easy entry into use of your measuring device.

The TECHKON team used great care in producing this manual. Nevertheless, we cannot fully exclude mistakes. TECHKON GmbH and the authors cannot be held liable for any possibly incorrect statements nor their consequences. Products named that are not made by TECHKON are mentioned for information purposes exclusively and such statements do not represent trademark infringement. All registered trademarks are recognized.

Do you have suggestions for improvements or do you need information that goes beyond this manual? We would be glad to hear from you because your suggestions or questions are an important contribution to the continuous optimization of our manuals.

Visit us at: http://www.techkon.com Version 1.0 - 1998

Here’s how you can reach us: TECHKON GmbH Wiesbadener Str. 27 D-61462 Königstein Tel: ++49 - (0)6174 - 92 44 50 Fax: ++49 - (0)6174 - 92 44 99 http://www.techkon.com e-mail: [email protected]

Packing list •

Color densitometer R 410/e with •

Charger with A/C adapter

•

Manual - Brief review - Calibration chart - Registration card

•

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Case for device

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TECHKON ManualWelcome

About this manual

Product description

About this manual

The color densitometer R 410/e has diverse applications ranging from quality assurance in the proof and print sector to computer-to-plate to calibration of color copiers.

If the expressions mentioned are partially new to you, just look them up in the glossary or in the corresponding chapter. There you will find detailed explanations.

TECHKON color densitometers are marked by their exceptionally simple handling. The high measurement speed and the possibility of transferring measurement data directly to a computer (PC, Mac) are important characteristics, especially in production where the time factor plays a great role. Equally important is high measurement precision. Only this combination ensures reliable quality control.

If you are starting operation of the TECHKON color densitometer for the first time, we recommend starting with Chapter 1 - Set-Up -.

All TECHKON measurement devices boast these characteristics. The color densitometers R 410 and R 410e provide the following measurement data at this standard of quality: • • • • •

Density and density difference Gray and color balance Dot percentage and dot gain Print contrast Print plate measurement - to Yule-Nielsen with determination of n-factor

For experienced users who want a quick introduction into operation, we have developed an overview card. You will find it in the cover. Detailed, subject-related description of operation begins in Chapter 2 - Densitometric Measurements - .

You should have yourself registered in any case. Only this way are we able to inform you of current updates. The registration card is located as the last page in this manual and can be removed.

The color densitometer R 410e offers the following additional functions: • • •

Trapping Color tone error (hue) Grayness

Both devices feature a data cable port for communication with a PC. More on this topic in Chapter 5 - PC and Software -.

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TECHKON ManualWelcome

Table of contents

Table of contents Welcome .................................................................. 3 Packing list ............................................................. 3 Product description ................................................. 4 About this manual ................................................... 5

1 Set-up .................................................................. 9 Safety tips ............................................................... 9 Setting up the measurement device ..................... 10 Turning the measurement device on and off ......... 11 Charging the measurement device ....................... 12

2 Densitometric measurements ......................... 13 Calibration on paper white .................................... 14 Density measurements - D1-mode ....................... 15 Measuring gray balance - D2-mode ...................... 16 Measuring color balance - D2-mode ..................... 17 Measuring dot percentage - %1-mode ................. 18 Saving solid density in %1-mode ..................... 20 Dot percentage according to Yule-Nielsen ....... 21 Measuring dot gain - %2-mode ............................. 22 Saving solid density in %2-mode ..................... 25 Measuring print contrast - %2-mode ..................... 26 Deleting all measurement values .......................... 26

3 SELECT-mode ................................................... 27 Special functions of the R 410e model ................. 29 Measuring trapping 1 (according to Preucil) .... 29 Measuring trapping 2 (according to Ritz) ......... 32 Measuring color tone error (hue) ..................... 33 Measuring grayness ........................................ 34 Entering screen-percentage-values (%-REF) ....... 36 Entering density-reference-values (DEN-REF) ..... 38 Entering white-reference-values (CAL-REF) ......... 39 Entering the Yule-Nielsen faktor n ......................... 41

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Basic calibration of the densitometer (SLOPE) ..... 44 Entering calibration chart values ..................... 45 Measuring calibration chart values .................. 46 Data transfer (SEND-mode) ................................. 47 Selection of language ........................................... 48

4 Care and Maintenance ..................................... 49 Calibration chart ................................................... 50 Reset function ...................................................... 50 Troubleshooting .................................................... 50

5 PC and Software ............................................... 52 TECHKON EXChange .......................................... 52 TECHKON QS Pro ............................................... 53

Set-up

1 Set-up This chapter includes: • • • •

Safety tips Please pay attention to the following safety tips: •

6 Technical Data .................................................. 54 Glossary ................................................................. 55 Manufacturer´s certificate .................................... 61

• • •

Registration card Overview card

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Safety tips Set-up of measurement device Charging the measurement device Turning the measurement device on and off

•

Verify that the A/C current available corresponds to the type of current on the decal of the A/C adapter. Make sure no powder or dust accumulates in the lower area of the measurement channel. Prevent liquid or vapors from penetrating the device. Handle the supplied calibration chart with care and choose a dark, dust-free and room- temperature place for storage. Use only original TECHKON accessories (charging console, data cable, Mac adapter).

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TECHKON ManualWelcome

Set-up

Setting up the measurement device The device is operated by four function keys and a start key. The green key starts measurements, the remaining four function keys call up select measurement functions.

function keys

display

The menu functions are split into two operational levels, measurement mode and select mode. The individual functions for measurement mode are explained in Chapter 2 - Densitometric measurements - . The functions for select mode are explained in Chapter 3 - Select mode - .

measurement head

connection port for data cablel

Measurement mode is the default mode at start-up. start button

The patented construction principle of the measurement head assures exact positioning on the measurement patches of the print control strip. Positioning is kept under control even during measurement. This permits reliable measurements of even extremely thin measurement patches.

reset key serial number

charge contacts

Turning the measurement device on and off

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Turning on:

Depress the green start button on the reverse side of the device.

Turning off:

The device shuts off automatically after five minutes if it is not operated during this time.

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TECHKON ManualWelcome

Densitometric measurements

Charging the measurement device If the available A/C current corresponds to the current on the A/C adapter decal, then: • •

•

Plug the A/C adapter into the wall socket. Put the measurement device onto the charging console. Both gold contacts on the bottom side of the measurement device (see Figure Chapter 1 - Set-up of the measurement device-) must fit into both sockets on the charging console. The direction in which the measurement device points is irrelevant. Charge the R 410/e at least one half hour.

The R 410 and R 410e devices are powered by environmentally-friendly and rechargeable NiMH batteries. The charge process is electronically controlled so that differently charged batteries are charged optimally and gently. It takes 4 hours to fully charge the battery. Full-charge is indicated by C = 100% in the display. With fully charged batteries the device can conduct 10,000 measurements. If the battery charge surpasses a certain threshold level, the LOW-BATTERY signal appears in the display before each measurement. At this point you can carry out another 100 reliable measurements. We recommend charging the device as soon as the LOW-BATTERY signal appears. After charging for about 30 minutes the device is ready to use again.

During the charge process the device automatically turns on and remains on until the A/C adapter is removed from the current.

2 Densitometric measurements In this chapter you will learn about the following applications: • • • • • • • •

Calibration on paper white Density measurements Gray balance Color balance Dot percentage Dot gain Print contrast Deleting indicated measurement values

In measurement mode the individual keys have the following functions:

%1+%2

D1+D2

Selection key for choice of %1- and %2-mode

Selection key for choice of D1- and D2-mode

Call-up of SELECT-mode SELECT

CLEAR + CAL

Delete measurement values Calibration on paper white

Data transfer to computer SEND

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Densitometric measurements

Calibration on paper white

Density measurements - D1-mode

To exclude influences of paper coloring and surface during evaluation of the printed color layers, the device has to be calibrated to the corresponding paper white.

D1-mode measures the full tone densities of the individual process colors. Measuring density:

Calibration on paper white: 1 Position the device on an unprinted spot of the print sheet. 2 Press the CLEAR+CAL key twice (double-click).

1 Select D1-mode with the D1+D2 key. 2 Position the device on the measurement patch selected. 3 Start measuring with the green start key.

%1+%2 D1+D2 SELECT %1+%2 D1+D2 SELECT

CLEAR + CAL

SEND

CAL B0.00 C0.00 M0.00 Y0.00

CLEAR + CAL

SEND

D1 B..... C..... M..... Y..... Density measurement

White calibration

The first click of the key deletes the old measurement values. The second click of the key starts calibration. Calibration is confirmed by two signals. Calibration can be repeated any number of times.

The measurement value will automatically be linked to the proper process color. The index letter of the color measured last will blink. Old measurement values of the remaining process colors remain on the display until they are substituted by new measurement values or are deleted by CLEAR. Be advised:

Be advised: If reference values for a certain standard of white are saved in the device, these reference values will appear on the display instead of zero-values (refer to Chapter 3 Reference values of white - ).

If the density value is smaller than D = 0.04, the device automatically switches from D1-mode to D2-mode since automatic recognition of the measured color is not possible at low densities. The D2 sign will blink as an indication of automatic and temporary selection of D2-mode. Once higher density values are measured, the device automatically returns to D1-mode.

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TECHKON ManualWelcome

Densitometric measurements

Measuring gray balance - D2-mode

Measuring color balance - D2-mode

Layered printing of the process colors cyan, magenta and yellow should result in a neutral gray during colorization to a standardized color scale. Excess of any one color results in a color imbalance.

Measuring color balance is identical to measuring gray balance.

Using the measured values, gray balance measurement indicates which color is causing a color imbalance.

Color balance indicates divergences of the printed tone from a given color sample. For this measurement, it is important to consider all partial densities since the color achieved may consist of different shares of the basic colors CMYB.

Measuring gray balance: 1 Select D2-mode with the D1+D2 key. 2 Position the device on the gray balance field. 3 Start measuring with the green start key.

%1+%2 D1+D2 SELECT

CLEAR + CAL

SEND

D2 B 0.80 C 0.79 BL M 0.78 Y 0.80 Gray balance

%1+%2 D1+D2 SELECT

CLEAR + CAL

%1+%2 D1+D2 SELECT

SEND

D2 B 0.33 C 0.02 BL M 1.16 Y 1.37

SEND

D2 B 0.80 C 0.73 BL M 0.70 Y 0.87 Gray balance with a surplus of yellow

D2-mode measures all four partial color densities (CMYB) of a single control patch. The partial color densities of the process colors and the respective black density appear in the display after each measurement.

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CLEAR + CAL

Example: A “red” printed with the process colors magenta (M) and yellow (Y) and which serves as a reference sample.

%1+%2 D1+D2 SELECT

CLEAR + CAL

SEND

D2 B 0.33 C 0.02 BL M 1.04 Y 1.37 Divergence of magenta (M) on the print sample.

For definition and compliance of tolerance values, divergence can be measured directly as a density difference. For this the device needs to be calibrated on a reference sample and not on paper white.

Calibration on a reference sample is performed as described in Chapter 2 - Calibration on paper white -.

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TECHKON ManualWelcome

Measuring dot percentage - %1-mode The measurement procedures consists of two measurements that are made in sequence. For this a single color’s solid patch and the corresponding screen patch are measured. The result is the percentage dot percentage of the screen patch. Dot percentage is calculated according to the Murray-Davis formula and describes effective dot percentage to DIN standard. This measurement process is especially pertinent for recording copier index lines of print plates and of print index lines for print sheets. The color of the measurement patches is automatically recognized and displayed. In measuring on print plates, the very differentiated colorization of the print plates is automatically considered. This occurs by selecting the color channel with the highest density difference between the exposed and unexposed areas. This results in a high measurement accuracy on all print plates.

Densitometric measurements

After measuring, the measured density values and the index letter for the color will initially appear on the display. These figures are automatically followed by the measured dot percentage DP in percent.

%1+%2 D1+D2 SELECT

%1

CLEAR + CAL

SEND

SD 1.62M DD 0.94

Density values and index letter of the color

%1+%2 D1+D2 SELECT

%1

CLEAR + CAL

SEND

SD 1.62M DP 91%

Dot percentage

Upon termination of a measurement cycle, a new measurement can start immediately. It is not necessary to delete the old measurement. By displaying the solid density SD, the measurement process encompasses density measures in D1-mode and can thus be used as a universal measurement procedure.

Measuring dot percentage: 1 Select %1-mode with the %1+%2 key. 2 In sequence measure the solid density SD and the screen density DD of a color.

%1+%2 D1+D2 SELECT

%1

CLEAR + CAL

For further information on the topic of dot percentage, request our Application Note 5.

SEND

SD ..... DD .....

%1-mode

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TECHKON ManualWelcome

Densitometric measurements

Saving solid density in %1-mode

Dot percentage according to Yule-Nielsen

By saving solid density SD, the measurement cycle can be restricted to measurement of screen densities DD when measuring step wedges.

The effective dot percentage, which is measured by reflection according to Murray-Davis, consists of two shares: a geometric share and an optical share. The geometric share is the surface relation of screen dots to paper white. The optical share is created through light diffusion around the screen dot designated as “light capture” and the irregular coverage of the screen dots.

Saving solid density: 1 Measure solid density SD at the start of a measurement cycle. 2 Press the %1+%2 key until an asterisk (*) appears adjacent to SD and the color symbol is displayed.

%1+%2 D1+D2 SELECT

%1

CLEAR + CAL

SEND

SD* 1.62M DD .....

Saving solid density

The saved value of SD can be deleted with the CLEAR key or by white calibration.

The Yule-Nielsen factor n determines geometric dot percentage. This measurement procedure is used, e.g., for measurements on print plates. For print plates only the geometric share is of interest since only this share is colored and printed. The n-factor is displayed in %1-mode as soon as it is entered and effective. %2-mode always measures without n-factor.

For further details refer to Chapter 3 - Entry of YuleNielsen factor n - as well as the glossary. For further information about this topic request our Application Note 3.

You can now save a new value of SD or commence new measurements without saving.

Be advised: Only one value of SD can be saved. The saved value of SD is shown continuously on the display.

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Measuring dot gain - %2-mode Dot gain is one of the most important key numbers in print standardization. Due to mechanically induced dot gain in printing, color tones turn darker. Different factors play a role, e.g.: •

•

The printing color is absorbed by the paper and consequently dies a surface area larger than the corresponding screen dot. The rubber sheet is soiled and causes dot gain during transfer from rubber sheet to the print medium.

The measurement procedure consists of three measurements which are effected in sequence. First the solid patch and two screen patches of a color are measured. One screen patch is assigned to the range of deep tones (80%) and one to the range of medium tones (40%). The screen patches of the print control strip must correspond to the screen-percentage values saved in the device. Measuring dot gain: 1 Select %2-mode with the %1+%2 key. 2 In sequence measure solid density SD and the two screen densities DD (e.g. 80% and 40%) of a color.

Densitometric measurements

After measuring, the display initially shows the measured density values,

%1+%2 D1+D2 SELECT

CLEAR + CAL

SEND

%2 80%+40% SD 1.62 DD 0.94 DD 0.38 M

Density value screen patch

Density value solid patch

Index letter for color

Screen-percentage values

then automatically the values for dot percentage, dot gain and print contrast.

%1+%2 D1+D2 SELECT

CLEAR + CAL

SEND

%2 80%+40% C 0.42 11/91% 19/59% M

Print contrast

The order of measurements is irrelevant. Dot gain in %

Dot percentage in %

Upon termination of a measurement cycle, a new measurement can commence immediately. It is not necessary to delete the previous measurement values.

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If your print control strip displays different screen patches, you can adjust the screen-percentage values of the device in SELECT-mode to the screen patch of your print control strip (e.g. to 70% and 30%). The default adjustment of the shipped densitometer is 80% and 40%.

Densitometric measurements

Saving solid density in %2-mode Solid density SD can be saved as a reference value. This permits faster implementation of comparative measurements. Saving solid density:

Further details on adjusting the screen-percentage values are in Chapter 3 - Entry of screen-percentage values -. For further information on this topic request our Application Note 5.

1 Measure solid density SD at the start of a measurement cycle. 2 Press the %1+%2 key until an asterisk (*) appears to the right of SD.

%1+%2 D1+D2 SELECT

CLEAR + CAL

SEND

%2 80%+40% SD* 1.62 DD..... DD..... M Saving solid density

The saved value of SD can be deleted with the CLEAR key or by white calibration. Afterwards a new value of SD can be saved or a new measurement without saving function started.

Please be advised: Only one value of DV can be saved. The saved value of DV appears in the display during every measurement.

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SELECT-mode

Measuring print contrast - %2-mode A print-out should have a maximum of contrast, i.e. the solids achieve a high color density. The printed screen dots provide the corresponding contrast. An increase in the color density of the individual screen dots increases this contrast. When a given limit is surpassed, the screen dots tend towards fullness and thus the amount of paper white - contrast - diminishes. By controlling the screen dots via a measurement of print contrast, you can achieve an optimum of coloring. Print contrast is always linked to a measurement of dot gain and dot percentage. Correspondingly measurements of dot gain automatically furnish the related print contrast. The measurement process is described on page 21 - Measuring dot gain -.

3 SELECT-mode Select-mode provides a second operational level. The following measurements and adjustments are available:

%1+%2 D1+D2 SELECT

CLEAR + CAL

SEND

1 TRAPPING 1 2 TRAPPING 2 3 HUE

If you want to measure only print contrast, you need to measure the halftone patch of the deep tone area twice in order to complete the measurement. For further information on this topic please request our Application Note 5.

Special functions of the R 410e

4 GRAYNESS 5 %-REF-VALUES 6 DEN-REF-VALUES 7 CAL-REF-VALUES 8 YULE-NIELSEN

Deleting all measurement values In order to delete all measurement values or return an incomplete measurement cycle to the starting point, press the CLEAR+CAL key.

9 SLOPE-VALUES 10 SLOPE-MEASURE 11 TRANSMISSION 12 LANGUAGE

Switching to SELECT-mode requires the following simple steps: (refer to next page). 26

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•

Press both the %1+%2 and the D1+D2 keys (=SELECT) at the same time and keep pressing until the first menu function (TRAPPING 1) appears in the display after approximately 2 seconds.

SELECT-mode

Special functions of the R 410e model The R 410e densitometer features four special functions in comparison to the R 410 model, as mentioned at the beginning of Chapter 3 - SELECT-mode -.

Measuring trapping 1 (according to Preucil) %1+%2 D1+D2 SELECT

CLEAR + CAL

SEND

YES NO CONTINUE 1 TRAPPING 1 Function 1 in SELECT-MODE

• • • •

Press one of the two keys (CLEAR+CAL or SEND) above CONTINUE to select a function from the list. Press the %1+%2 key above YES to activate the indicated function. Press the two keys %1+%2 and D1+D2 (=SELECT), at the same time to leave the function. Press the D1+D2 key above NO to leave SELECTmode.

Be advised: You can switch an indefinite number of times between the individual menu function with one of the two keys above CONTINUE. Function 1 always follows the last function. If no key is depressed within 2 minutes in SELECT-mode, the device turns off automatically. Upon restarting with the start key, the device is once again in measurement mode.

By measuring trapping you can determine how two colors printed on top of each other relate. The trapping value TR (percent) indicates whether the subsequent second color was absorbed equally well by the first color (TR = 100%) or worse (TR smaller than 100%) in comparison to absorption on virgin paper. The result of the measurement is calculated according to the Preucil-formula (see glossary). Measuring trapping: 1 Switch to SELECT-mode via the two SELECT keys. Trapping 1 appears on the display. 2 Register Trapping 1 with the key above YES. The function selected will appear on the display for approximately 1 second and then the register for the measurement cycle.

%1+%2 D1+D2 SELECT

CLEAR + CAL

SEND

TR1-MEASUREMENT STOP WITH SELECT Function selected

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%1+%2 D1+D2 SELECT

TR1 C+M D2.....

CLEAR + CAL

SEND

D1..... D12....

Measurement cycle register

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TECHKON ManualWelcome

SELECT-mode

3 Select the desired color order with the key above C+M. The following color orders are possible: C+M, C+Y, M+C, M+Y, Y+C, Y+M 4 Measure in sequence the first-printed color D1, the second-printed color D2 and their layered print D12 with the green start key.

Please adhere to the order indicated for the individual measurements.

Please be advised: The measurements of a measurement cycle are implemented with the filter of the second-printed color. That is why very low density values will be measured for the first-printed color.

For further information on this topic request our Application Note 4.

5 To leave the function trapping 1: • Press both SELECT keys. • Press the key above NO. At the end of a measurement cycle the trapping value in % and the three density values D1, D2 and D12 appear in the display.

%1+%2 D1+D2 SELECT

CLEAR + CAL

SEND

TR1 C+M 73% 0.32 1.26 1.24 D1

D2

trapping TR

D12

Upon output of the measurement values, a new measurement cycle can start. It is not necessary to delete the previous values.

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SELECT-mode

Measuring trapping 2 (according to Ritz)

Measuring color tone error (hue)

The result of the measurement is calculated according to the Ritz-formula (see glossary).

The measurement function of color tone error (hue) is used in checking print colors. Hue measures the divergence of the printed, real color from an ideal, theoretical print color. Since there are no ideal print colors and hue accordingly will always exist, only the change of hue is judged.

The measurement process is identical to the measurement for trapping 1: 1 Switch to SELECT-mode via the two SELECT keys. 2 Select trapping 2 by depressing the key above CONTINUE. 3 Register trapping 2 with the key above YES. 4 Select the desired color combination with the key above C+M. 5 Measure in sequence the first-printed color D1, the second-printed color D2 and their layered print D12 with the green start key.

Please adhere to the order of the colors to be measured.

6 To leave the function trapping 2: • Press both SELECT keys. • Press the key above NO.

The hue of a measurement at the start of a printing process thus serves as a reference for further control measurements during the print run. For further information please refer to the glossary. Measuring hue: 1 2 3 4 5

Switch to SELECT-mode via the two SELECT keys. Select hue by depressing the key above CONTINUE. Register hue with the key above YES. Measure with the green start key. To leave the function hue: • Press both SELECT keys. • Press the key above NO.

The print color is measured at the start of the printing process and as a control during the print run. The change in color tone error (hue) indicates whether and how much the color tone of a color has changed.

Be advised: Only print colors with the same solid densities can be compared.

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SELECT-mode

Upon measurement the color tone error (HU-value) in % and the partial color densities (in order of size) of the color scale appear in the display.

The print color is measured at the start of the printing process and controlled during the print run. Upon measurement, the grayness (GR-value) in % as well as the largest and smallest value of the partial color densities of the colored process colors appear in the display.

%1+%2 D1+D2 SELECT

HU 41% Y 0.61

CLEAR + CAL

SEND

M 1.40 C 0.05

%1+%2 D1+D2 SELECT

HU 46% Y 0.66

CLEAR + CAL

SEND

M 1.41 C 0.03 %1+%2 D1+D2 SELECT

Example: Two colors magenta with different color tone errors in cause of different partial color density in yellow.

GR 4% Y 0.39

CLEAR + CAL

SEND

C 0.06

Grayness of yellow

Measuring grayness The sequential printing of the four colors cyan, magenta, yellow and black causes a color drag in the printing machine. With the measurement function of grayness, it is possible to check how “clean” the print colors are and confirm the extent of color drag in the printing machine.

This comparative measurement indicates whether color drag occurred during the printing process and indicates the corresponding counter measures, if any.

For further information please refer to the glossary. Measuring grayness: 1 2 3 4 5

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Switch to SELECT-mode via the two SELECT keys. Select grayness by pressing the key above CONTINUE. Register grayness with the key above YES. Measure with the green start key. To leave the function grayness: • Press both SELECT keys. • Press the key above NO.

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Entering screen-percentage-values (%-REF) For the measurements of dot gain and print contrast (%2-mode) the screen densities of the deep tone area and the medium tone area can be manually adjusted. This permits adjustment to the screen patches in the print control strip. This adjustment is necessary for a correct calculation of dot gain and print contrast.

SELECT-mode

Tips for entering: • You can enter %-reference values between 1 and 99. • Depressing the keys above the + sign automatically counts upwards. • The longer one of the keys is depressed, the faster numbers count upwards. • Depressing the green start key recalls the standard values (80% and 40%) to the display.

Entering halftone percentage values: 1 Switch to SELECT-mode with the two SELECT keys. 2 Select %-REF values by pressing the key above CONTINUE. 3 Register %-REF values with the key above YES. 4 Enter the screen-percentage values of the print control strip used with the two keys above the + sign.

%1+%2 D1+D2 SELECT

%-REF

CLEAR + CAL

SEND

+ + 80% 40%

Screen-percentage values

5 To leave the function %-REF values: • Press both SELECT keys. • Press the key above NO. For control purposes, select %2-measurement mode and confirm that the adjusted values appear in the display.

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Entering density-reference-values (DEN-REF) The R 410/e model automatically indicates differences in density values between a color patch with a given density and several color patches to be measured.

SELECT-mode

D1-mode indicates density-difference-values. This occurs by subtracting the reference values from the corresponding absolute density value measured

Please be advised: Reference values are only effective in D1-mode.

Entering density reference values: 1 Switch to SELECT-mode via the two SELECT keys. 2 Select DEN-REF values by depressing the key above CONTINUE. 3 Register DEN-REF values with the key above YES. 4 Enter density-reference-values with the keys above C, M, Y and B.

%1+%2 D1+D2 SELECT

C 150

M 152

CLEAR + CAL

SEND

Y 144

B 185

Density-reference-values

5 To leave the function DEN-REF values: • Press both SELECT keys. • Press the key above NO. Upon entry you can conduct density measurements in D1-mode. Density is measured as described in Chapter 2 Density measurements - D1-mode-. The letter R (for density-reference-value) will appear in the display below D1.

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Tips for entry: • You can adjust reference values of D = 0 until D = 2.50. Enter without the period. • Depressing the keys above the corresponding color automatically counts upwards. • The longer you depress one of the keys, the faster numbers count upwards. • Depressing the green start key resets the values to zero.

Entering white-reference-values (CAL-REF) Before measuring, densitometers need to be calibrated to zero on the corresponding paper white of the print sheet. This excludes influences from the paper coloring or surface in evaluating the color layers printed. For certain applications, however, it makes sense to enter white-reference-values in order to compensate for density divergences caused by the use of differing print mediums. If, for instance, one wants to print on an older print sheet, one way to do this is through a white calibration on the reference white (standard paper white) with the R 410/e model. Then it is possible to conduct a density measurement on the older print sheet. The indicated density values are entered in the CAL-REF menu. Upon calibrating the colors on the older print sheet, you can measure and receive the density values of the print color for the new print sheet.

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SELECT-mode

Entering the Yule-Nielsen factor n

Entering white reference values: 1 Switch to SELECT-mode via the two SELECT keys. 2 Select CAL-REF values by pressing the key above CONTINUE. 3 Register CAL-REF values with the key above YES. 4 Enter white-reference-values with the keys above C, M, Y and B. 5 To leave the function CAL-REF values: • Press both SELECT keys. • Press the key above NO.

%1+%2 D1+D2 SELECT

C 6

CLEAR + CAL

SEND

Y 12

B 8

M 4

Entered reference values

%1+%2 D1+D2 SELECT

CLEAR + CAL

The effective dot percentage, which is measured by reflection, consists of two shares: a geometric share and an optical share. The geometric sector is the surface relation of screen dots to paper white. The optical sector is created by light diffusion around the screen dot called “light capture” as well as the irregular coverage of the screen dots. By adjusting the Yule-Nielsen factor n, the optical sector can be calculated from the measured effective dot percentage so that only the geometric share is shown. This measurement process is used, for example, in measurements on print plates. For print plates only the geometric share is of interest since only this share is colored and printed.

SEND

CAL B 0.08 C 0.06 REF M 0.04 Y 0.12 Display during white calibration

For control purposes, you can select D1 or D2-mode to conduct a white calibration. REF (for reference value) will appear on the display below CAL and the entered white-reference-values.

Entering Yule-Nielsen factor n: 1 Switch to SELECT-mode via the two SELECT keys. 2 Select Yule-Nielsen by pressing the key above CONTINUE. 3 Register Yule-Nielsen with the key above YES. 4 Press the keys above CLEAR to bring up the register for measurement. At the same time the n-factor is reset to 1.00.

Tips for entry: • You can enter reference values of D = 0 up to D = 0.25. Enter without periods. • Depressing the keys above the respective color automatically counts upwards. • The longer you press one of the keys, the faster numbers count upwards. • Pressing the green start key resets the values back to zero.

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%1+%2 D1+D2 SELECT

CLEAR + CAL

CLEAR n 1.00 Resetting the n-factor

SEND

%1+%2 D1+D2 SELECT

SD .... n 1.00

CLEAR + CAL

SEND

DD ....

Register for measurement

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TECHKON ManualWelcome

SELECT-mode

5 Measure solid density SD and screen density DD.

Please be advised:

The screen patch DD to be measured should be made up, as much as accurately possible, of 50% geometric screen dots. The relation is best seen with rectangular screen dots. At a geometric dot percentage of 50%, when the picture is viewed with a magnifying glass, a chess-square pattern emerges where the tips of the screen dots just touch.

In entering the n-factor, the measured dot percentage values of DP must be between 10% and 90%. Otherwise the device will show that the DP-value is either too large (DP>>) or too small (DP