Standard Finishing


No announcement yet.

Dot pattern?

  • Filter
  • Time
  • Show
Clear All
new posts

  • Dot pattern?

    What is everyone using?
    We're using screen/trueflow with what they call a square dot; it doesn't keep the roundness, it expands and contracts as needed.
    The pressman want to try an eliptical.
    Any thoughts?


  • #2
    Re: Dot pattern?

    Tell the pressman you'll give them what they get and they'll be happy to have it!

    Why the nerve of them ink monkeys.

    But seriously folks, chain (connecting squares in the midtone forming a chain, round in the sh and HL, or euclidean, with a round in their from time to time.

    Mostly in my past its been some form of euclidean.


    • #3
      Re: Dot pattern?

      We use a square dot screen from Harlequin/Fuji.

      Square dot will give the sharpest result (ctp helps to alleviate the need for that much sharpness).
      The drawback is in tone jump at the 50%, say a ship's hull where the 50% dot (checkerboard) occurs, you may/will get a visible 'tone jump' usually in one or two colors.
      Elliptical dots cause the joining of dots at something like 43% in one direction and 63% in the other, which smooths out the ship's hull but also smooths out everything else. It's great for cosmetic jobs and other 'softer' images.
      It is my opinion (only) that today's screening methods work well either way. Personal prefs for me is square dot



      • #4
        Re: Dot pattern?

        In a CTP environment the best AM/XM dot shape is round. By that I mean a non-transforming dot that is round in the highlights and simply increases in size to represent darker tones. Here are a few reasons why this is the "best" dot shape for CTP compared to Euclidean, Elliptical, Square, etc. dot shapes:
        1) Dot shape is the same for all screen angles - eliminates dot gain due to dot shape variables, reduces single channel moiré issues
        2) Dot is non directional, i.e. all screen angle dots are equally react the same to directional press issues such as slur and doubling
        3) The tone bump that occurs when dots touch occurs in the shadows at 75% so is much less visible in presswork (e.g. vignettes/skin tones) compared to Euclidean (50% bump where dots form a checkerboard) or Elliptical 40% & 60% bump.
        Round dot is not normally used in a film workflow because, with linear film, the dots touching in the 3/4 tones results in a loss of shadow detail.

        thx, gordo


        • #5
          Re: Dot pattern?

          If that's the case why aren't the majority of ctp users using round exclusively?

          (plus round is so 1985)



          • #6
            Re: Dot pattern?

            If that's the case why aren't the majority of ctp users using round exclusively?

            (plus round is so 1985)


            I have my suspicions as to why they don't.

            thx gordo


            • #7
              Re: Dot pattern?

              We use the round dots with good success. I've seen better screening with Artwork Systems' new screens they've had in the last 2-3 years, but we've stuck with round because our customers most likely wouldn't be able to tell the difference.



              • #8
                Re: Dot pattern?

                I agree with Gordon and Don. I think round dots are the best dot shape for AM (and hybrid) screening. If you are looking at the printed results from an unlinearized (no curve) plate, you will find that you can get roughly the same dot gain (at 50%) on press with 200 linescreen elliptical dots as you do with 240 linescreen round dots. So using round dots allows you to print at a higher linescreen without having to make a more radical linearization/calibration curve.

                Abe Hayhurst
                Director of Color and Technology
                We Do Graphics, Inc.


                CanonKBAAvantiSmartsoft (Presswise)DuploXerox4Over

                Canon Embellishment White Paper


                Print Embellishment Goes
                Straight To The Bottom Line

                InfoTrends reported that interviews with more than 100 print customers demonstrated an appetite and willingness to pay premiums of 24% to 89% for special effects, over CMYK-only printing. They also indicated embellishment could apply to a significant portion of their work. Embellishment options can include hot foil stamping, spot gloss UV, embossing, debossing, letterpress, diecut shapes, lamination, duplex, triplex, gold foil, silver foil, copper foil, white foil, black foil, clear foil, etching, and laser cutting techniques. Download The Free White Paper.

                CanonSmartsoft (Presswise)AvantiKBAXeroxChili publish4Over " "DuploAvanti

                What's Going On


                There are currently 7247 users online. 95 members and 7152 guests.

                Most users ever online was 14,674 at 05:29 AM on 10-30-2019.