Poor quality LO pattern fill in pdf export


#1

Hi,

I’m using LO pattern fill for hatching cross sections. Whilst this looks fine in LO, when exporting toExample.pdf (2.2 MB) pdf the pattern fill linework becomes broken and wiggly, giving a poor quality appearance (see diagonal hatching on top of walls on section cuts in attached file).

I have all quality settings turned on high in SU and LO. I’ve also tried all permutations of settings in Bluebeam, my pdf viewer.

The problem occurs when viewing with Bluebeam, Acrobat and Mac Preview and prints are also affected. However, when viewed on an iPad the drawings are perfect! It seems as if the quality is there, but there’s a viewing problem with pdf output. This only occurs with the LO pattern fill, all hatches, lines and textures brought in with the SU model reproduce fine on the pdf.

Any solutions would be gratefully received as the drawings don’t look professional as they are.

Cheers

David


#2

To me it looks like your PDF viewer is downsampling raster patterns to gain speed.

Anssi


#3

how are your PDF viewing ‘Preferences’ set in ‘Preview.app’?
john


#4

They appear to be ok. I’ve tried adjusting and it doesn’t help. There is a lot more adjustability and options in the Bluebeam preferences but they don’t appear to help either.

D


#5

Hi David-

I’d like to do some investigation on your file, if it’s something that you can share? I’ll send you my email in a PM if you’d like to keep the file more private.

Thanks,
Marc


#6

Here is a screenshot of your wall viewed at 690% in Adobe Acrobat Pro 9.0:


To me it looks good despite the magnification. Of course, the patterns are raster images, so if you look near enough, it will always start to show.

Anssi


#7

Hi Anssi,

I agree that looks fine. It looks like what I see when I view the drawings on an iPad, but unfortunately not on any of the other pdf viewers Ive tried.

I’ve sent some files through to Mark and I gather the matter is being looked into. I’ll update this thread when I hear back.

Thanks for your help.

David


#8

Update - Did anything ever come of the investigation into this problem, that I was advised was a bug in Layout? I assume not as I’ve just upgraded to 2016 and the problem remains - see attached pdf file, which is supposed to be a straight diagonal ‘steel’ hatch, output to high quality pdf.

Shortly after last years dialogue we switched to using Skalp for all our section/hatching work, which has solved the problem for us. However, its disappointing that what appears to us to be a fundamental problem with Layout hatches still remains.layout.pdf (2.1 KB)


#9

I would say that the problem lies rather with PDF viewers and modern monitors than with LayOut by itself. Black and white raster graphics just don’t scale well on a computer screen, you get moiré and other artifacts. Like the file you posted. I admit the hatching looks pretty awful when viewed in a full page view, but look at the enlarged screenshot:

As you see, lack of resolution is clearly not the problem here, and if you print this to paper the result will probably look quite OK.

It is a lesson I learned quite early: If you do things that are to be shown on a computer screen, or, worse, through a projector, avoid black and white linework, and create images that are presized for the intended resolution. Photoshop can downsample an image much better than your garphics card, a PDF viewer or PowerPoint.

Anssi


#10

Hi Anssi, thank you for the reply - I think we’re in danger of going round in circles though.

The sample I attached in my previous post was an A3 sheet and if it’s printed it comes out as it looks on screen, broken wiggly lines and totally unacceptable for construction drawing use. That was the reason I originally raised the issue. We find layout hatches with straight line elements unusable, hence we switched to Skalp, which works fine.

We reproduced the effect last year on 3 different machines with different layout licences and 3 different pdf viewers (Adobe/Bluebeam/Preview) and the results were the same on all.

We were told it was a bug and all our files were submitted for investigation last year. Nothing has happened and the problem still occurs in SU2016 hence I’m raising it again now.

Regards

David


#11

This is still a problem in Layout 2017. Will the line hatching capabilities be improved in Layout?


#12

Try Foxit Phantom PDF. I viewed the “example” with a zoom of 600% and all looked great .
BTW
It also printed good.


#13

Thanks for the suggestion, but the reality is that Foxit Phantom PDF is of no use. The industry standard for sharing construction documents in the construction industry is Bluebeam, so if Layout hatches don’t work in Bluebeam, they don’t work at all.


#14

Hi Donald,

As far as we’re concerned you’re right, they are unuseable and we have to use Skalp to get acceptable quality hatching.

We made the case as clearly as we could in this thread and verified it on multiple platforms/software. Unfortunately the responses don’t indicate any acceptance that there is in fact a problem. So after 2 1/2 years don’t hold your breath for a solution.