Point Shape

Andrei83

Active member
Hello, the shape of the point on the plate is not smooth, the edges are torn with notches. Why is this happening and is it normal??? How will this affect the print run? Lineature 175. The resolution on our CTP is 2400-2540.
 

Attachments

  • IMG_20210612_223001.jpg
    IMG_20210612_223001.jpg
    237.4 KB · Views: 64
  • IMG_20210612_223016.jpg
    IMG_20210612_223016.jpg
    212.8 KB · Views: 63

gordo

Well-known member
Hello, the shape of the point on the plate is not smooth, the edges are torn with notches. Why is this happening and is it normal??? How will this affect the print run? Lineature 175. The resolution on our CTP is 2400-2540.
Looks normal. What RIP are you using?
 

gordo

Well-known member
Reminds me of the Harley Davidson logo :)
Perhaps Gordo was speaking to the sharpness of the dots and not the shape?
Those are odd indeed.
View attachment 290763

Yes, I was referring to the sharpness of the dots and not their shape. To me that rules out the CTP as a problem - assuming that there is in fact a problem.

Here's some dots straight out of a RIP.

1200.jpg


Download and look closely (at least 200%). Look familiar?

The job of the CtP is to image the dots that exit the RIP precisely. The dots on the plate should look almost identical to the dots that exit the RIP.
 
Last edited:

gordo

Well-known member
True, i just wondered if this shape is due to lower input resolution

The shape of the dot in a flat tone area is not much affected by the resolution of the input file nor the output device resolution.
The jaggedness of the dot's perimeter on the other hand will be more jagged when imaged at a lower output resolutuion. I.e. the dots of a 1200 dpi output bitmap will be more jagged than those of a 2400 dpi output dpi.

On the left is a 175 lpi round dot at 1200 dpi and on the right the same tone/lpi/round dot shape imaged at 2400 dpi:

Dotz.jpg
 

johnny_jay

Well-known member
I asked about shape to try and recreate. The attached is heavy elliptical saved out of Prinergy 2400 dpi, 175 line screen.
 

Attachments

  • file copy.png
    file copy.png
    18.9 KB · Views: 30
  • 25.png
    25.png
    3.5 KB · Views: 25
  • 75.png
    75.png
    3 KB · Views: 25

Canon Research

Canon
ENHANCING THE PRINT CUSTOMER CONNECTION
Delivering Client Experiences That
Build Competitive Ad-vantage


Download the White Paper

   
Top