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Introduction: Printing is widelyε©↕" used in daily life, and i''t is commonly used everywhere. In$∞' the process of printing, there are ≠&many factors that affect the printin↔α₩g effect, so when prinδλting, we will first print out♣↕≥ samples and compare them wi÷★th the sample sheets to prev&×ent errors and correct them ©₩in time to ensure the perfection ₽↑∞←of the printed matter. ≈♣We will share some reα∞&quirements that we should pay a←γβttention to when we look at the s™✘₹•amples for printing.σ€₽ The content is for you≠ €¶r reference: printing sample is the moλ↔>÷st common method used ✘ ±to check and control the printing quali∞£β✘ty in the process of printing oper £∑ations, whether it is monoc¶↕hrome printing or color printing,α" Operators must frequently use their$↕ own eyes to repeatedly compare the pri&γ↔εnted product with the sample§∑₩£, in order to identify the diσ←÷fferences between the printed produ∞¶₽÷ct and the sample, and promptly corre×↓≤φct them to ensure the quali↔™ty of the printed product.
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There is a difference εσbetween viewing samples undπππer colored light and und≠±÷¥er sunlight. In production pr™σ≤actice, most of the work is do✔€ε÷ne under the illumination ↕of a power source, and eac₹∞h light source has a certain <©¶color. This poses certain difficul↓"∞ties in correctly judging the co©£lor of the original &β☆manuscript or product. ±When viewing under co™↑∏™lored light, the color changes are gen®✔&erally the same color becoming lighter ♣©and the complementary color becoming dσ€↔←arker. For example, when vi™≈₽$ewing under red light, red beco₹ mes lighter and yellow becomes →orange& nbsp;& nbsp;& nbsp;♠↑ Green darkens, cyan da £rkens, and white turn♥"s red. Viewing colors under gree×✔δn light, green becomes lighte•≤'r, cyan becomes lighter, yellow be★↑≠comes greenish yellow, red becomes bσβ≠lack, and white becomes green. There is✘α≤≥ a difference between v< ±iewing samples under colo÷©γ¥red light and under sunlight. In pro↕±±duction practice, most of the work is d&one under the illumination o∞¥÷αf a power source, and each>≠ light source has a certain col ★or. This poses certain diffi≈✔culties in correctly judgin•₩'₩g the color of the original manuscript >>≤σor product. When viewing colors u ®₽&nder colored light, the color chaβ★λ±nges are generally the same colo•∏r becoming lighter and the compleπ♠mentary color becoming↓$ € darker& nbsp;& nbsp;÷>®& nbsp; For example, when ★≠♦viewing colors under red light, red→σ®∞ becomes lighter, yellow becγλomes orange, green becomes darker, cya₽♦n becomes darker, and white becomes∏↕ red. Viewing colors under green l♠Ωight, green becomes lγ↕ighter, cyan becomes lighter, ye★♣↕llow becomes greenish yellow, r ®&ed becomes black, and white§≈ becomes green.
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The intensity of light directl& ↓'y affects the judgment of the color♥' ≤ of the printed sample. The intensity ®< of light not only affects the ↑↔βbrightness of the color, but also chan ★ges the appearance of×φ↑ the color& nbsp;&¥§'; nbsp;& nbsp;& nbsp; Uδαsually, we observe a cylinder that re∑$•ceives light, with th×≠φ×e facing side being briσ>φ♦ght and the backlighting side bein♣≥↕ g dark. The combination of ligh£"t and dark is the middle tone. The same←←☆ object, under standard light source¥✔♠γs, is a positive col&π♦•or. If the light gradu≥© ∏ally becomes stronger, its co䀶€lor tone also changes to a bright π&hue, and the brightness increases to a ✘∞φcertain extent. Any colo♣↕♥"r can turn white. Bl'≤✔ ack porcelain also has white÷≤ reflective points, as the light at t&πφ•he reflective points is conce<§✘☆ntrated and strongly≠☆×¥ reflected.
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Why is there a sequential co≥≠lor contrast reaction? This is becauπ'$se the color you first look at excite≠®σs the colored nerve fibers of that co&>₹ lor, and then immediately looks a•'♠•t another color. Othπ"×er colored nerves quickly excite and c₩≠€ause color sensation↕₽♠, while the colored nerve that first∏≥λ↓ looks at the color €Ω↓€is in a state of inhibition after £₩Ωexcitation, and then the exci€ ↑tation is slower, causing a negative ↓±₽color response. This reactio≤↕σγn, combined with the new hue of the col≠₽or, forms a new color, so t★'βhe color is changed after vi←β♠®ewing. Moreover, there is still a regu<☆lar pattern of color ←£↕changes, which focus ↑ on the complementary aspe€♥≤ct of looking at the•☆× color first. Understa₽ ≤nding the above three as☆☆pects and mastering their cha≠πnging patterns, we should pay γ"₹σattention to them when actually vie §wing samples, in order to ensure th'σ©e stability and improvement of pri♠&γnting product quality. Printed materia↔÷'ls are divided into mo' γnochrome printing and colo∑σ λr printing. Monochrome printing is a p£™rinting method that §±¶is limited to one coloφ r. Color printing ca÷"←n print full-color pictu←res.
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In grayscale monochr♣☆λome printing, the deepestλ¥ solid base is 100%; White is 0↕&$≥%, and different sha♥ &des of gray are made by using diff£≈ ♥erent dots, that is, using percentπ↕☆age control. For ease of reading,σ ≈£ reversed white characters are usuall≥₽↕λy applied on a dark gray tone o∏☆≥f 50% to 100%, while black chaα★®racters are used bet♥∞<ween 50% and 0%. However, it sho×∞✘uld also be considered according to the§≠¥∞ different monochromes.
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