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    printing with out dotgain

    Being a long-term reader, I can predict in advance that "Gordo" is going to say the plate linearization step is unnecessary.
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    printing with out dotgain

    Do NOT adjust press settings (packing, pressures) or materials (ink) to adjust dot gain to visually match an old/legacy proof or previously printed sample (target). Prepress calibration or plate tone curves achieve the match (accuracy). The press then tries to replicate and reproduce the same...
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    What is the maximum variation for a paper sheet width than can be processed by most offset presses.

    Grain direction on sheetfed press should be long, which is parallel to cylinders. It's also parallel to longest dimension of landscape orientation paper sheet. Grain direction is important for register fit (wavy edge fanout) and wet ink marking due to stiffness of sheet transfer/transport...
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    Understanding Trapping Concepts for Flexo and Offset Printing

    Trapping is a prepress technique to compensate for misregistration that occurs in printing from the materials or the process. Less dimensionally stable materials/media (thin+ vs thick-, paper- vs film+) will need more trap compensation. Narrow web flexo is usually in-line or...
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    Tricks for finding a low spot in ink train rollers?

    I suggest running a "Dry" and "Wet" solids test. A dry solids test shows how inking system is working. Set the ink fountain keys to all the same value, uniform, even, balanced. It should print the same way. Then run the wet solids test. You need an imaged solid plate for this, with a 1"...
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    Flaring on a Heidelberg CX102

    "Blanking" or "Dusting" applies pressure between paper on impression cylinder and blanket. Dry dusting uses no dampening solution, wet dusting uses a plate, no inking, and applies dampening fountain solution. I'm wondering of applying water will make it even worse? Still curious about outer...
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    Flaring on a Heidelberg CX102

    Well.....you know the importance of temperature and humidity controlled press room (even over the weekend) and keeping paper barrier wrapped until after temperature conditioned and between passes. Just curious, if you fold the outer edge of wave edge sheet to the center, how much longer is the...
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    Flaring on a Heidelberg CX102

    Are you trying to register fit 1st pass to 2nd pass same side or is 2nd pass backside not register fitting to itself? If it's a 5/c, can you use 1st unit under impression to flatten out paper? Is paper grain long? Is paper flat or is it wavy edged (outer length is longer than center)?
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    Balance of ink and water. Patches for control.

    The old GATF had a target of diagonal lines in front of a solid bar. Excess dampening (flooding, washout) would leave a low density "ghost" in the solid behind the diagonal lines.
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    PM Schedule for Halm Offset Press

    Some mfg user guides often include recommended PM schedule by daily, weekly, monthly, quarterly, yearly.
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    Dot splitting/pulling in 1 corner of the printed sheet (KBA Rapida)

    Microphotos were very helpful in explaining problem. Dot distortion looks more like a ghost double than an actual slur (elongation). It is directional, diagonal, but from top left to bottom right. I would guess paper distortion (wavy edge) would be from lower left to upper right) as it fans out...
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    XMF Plate Distortion Question

    Are the 4 out forms (files) all the same or are they different, a combo gang?
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    Colour Management - Flexo Corrugated

    Previous: "It's incorrect to say that the CMYK color gamut will not meet colour simulation for spot colours. some Pantone colours are easily reproducible using CMYK process inks, just not all PMS colours." It depends on your definition of "close-enough" or "good-enough" color match! For a...
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    Overtime: How was it printed? Part 2

    Letterpress will look very similar to flexo. Intaglio can also be identified by tactile touch, feel. It has a raised surface, but not the same as thermography or screen.
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    Improving the original

    Orange as a spot color is unique in that when you print at various ink film thickness (IFT) or solid ink density (SID), the color's hue changes. Thicker and darker is more red. Thinner and lighter is more yellow. I used to have all the ink draw down samples and spectral curves and CIE Lab...
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    multicolor press printing 2 and 3 colors

    Sorry, I don't understand the question? Are you asking where to position the spot colors on a 4/c process press? If only 4/c, I would put the spot color in the most similar color unit so wash up time doesn't require a longer "color" wash. Red's into Magenta. Blue's into Cyan. Orange's into...
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    Consistent colour

    Did you ever consider that if you idle the press between pulls, for that 2-3 min that you are adjusting ink keys, the oscillator/vibrator rollers are evening out the ink key settings. Then when you start back up it's taking time and sheets to show the actual ink setting from the fountain blade...
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    Consistent colour

    Variation is the result of change, either known (ink key adjustments) or unknown. Variation is the opposite of consistency or stability. All should define a duration or period between sheets. A common interval is every 500 shts. Any press stoppage will immediately cause color variation since...
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    Low Dot Gain. Again

    Just to rule out some software setting in the densitometer/spectro, are you using the same device to measure, not the brand or model but the same device?
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