Why poor display quality in all PDF readers except those from Adobe?

17

3

When I read PDF files with Adobe Reader or Adobe Acrobat Pro, the display quality is superb. However, for the same files, other PDF readers like Foxit Reader, Sumatra PDF Reader, etc show poor quality: quite timid and fuzzy display. At least in Windows. In Linux systems, any reader is not satisfactory even the Adobe Reader.

Why? Is it because the PDF format is created by Adobe?


EDIT: Here are some sample screenshots. All viewers are set to zoom to page width.

(1) Sumatra PDF

Sumatra PDF

(2) PDF X-Change

PDF X-Change

(3) Foxit Reader

Foxit Reader

(4) BlueBeam

BlueBeam

(5) Adobe Reader

Adobe

To me, Adobe Reader clearly is the best. Especially look at the italic capital T.

Here is the sample PDF file.

Chang

Posted 2011-07-22T22:12:09.090

Reputation: 1 133

This viewer is unable to discern any superiority in the Adobe Reader sample. – kreemoweet – 2016-02-23T10:30:08.603

To me they all look blurry. – becko – 2016-04-03T10:41:46.190

FYI, using subpixel rendering will cause any user of monitor with subpixel scheme different from what you used to create these screenshots to see terrible image. – Euri Pinhollow – 2018-10-27T16:53:04.873

Answers

15

Only Adobe and Foxit (of those 5) have subpixel rendering. This is seen by zooming way in on the screenshot and seeing color fringing. This is because each pixel on an LCD display is made of 3 subpixels: red, green, and blue. These can provide extra resolution. Foxit maybe just doesn't have as good of a rendering method. Hinting could play a part.

Buge

Posted 2011-07-22T22:12:09.090

Reputation: 402

1+1. Actually hinting plays a large part. Adobe's font look better than Foxit's because Adobe's hinting tries to "flatten" circular strokes (such as the top and bottom arcs of the capital "S", and the lower-case "o"). The flattening reduces the transition of stroke width (thickness) from the sub-pixel anti-aliased (vertical) strokes to the non-aliased horizontal strokes. – rwong – 2014-04-18T22:33:44.470

1

I finally figured it out and I'm not an IT person (I'm a lawyer and I'm stubborn). I have used PDF Converter Pro 5.11 for several years and I love it. I continue to use it with Windows 10 so don't let anyone tell you it is not compatible. I can solve your problem for this program (PDF Converter Pro) but cannot address the same problems with other pdf programs. You might get some ideas from my solution though. So, I noticed that sometimes, pdf scans barely showed the text in PDF Converter Pro while appearing very nicely in Adobe.

I FINALLY found the solution. When you have your pdf document open in PDF Converter Pro, select the Tools drop down menu, then optimize pdf. There are three tabs, General, Images, and Fonts. You can play with the setting here to change sampling and compression. In the General tab, select "leave compression unchanged" from drop down menu. In the Images tab, select "leave original sampling" from the Sampling drop down and "leave compression unchanged" from the Compression drop down menu. Voila! All the text comes through clearly. I never take time to help others when I find solutions.....very selfish of me. Here, I struggled so long and nobody had the answer. I had to help out. Hope someone finds this after all these years as this is a very old thread!

user562488

Posted 2011-07-22T22:12:09.090

Reputation: 11

1

I think am pretty sure now that it's one of the rendering/smoothing options in Preferences->Page Display. Try changing them (there's quite a few) and seeing if it makes a difference.

Specifically:

If you change the "Smooth Text: For Laptop/LCD Screens" to "For Monitor", you'll see that it'll look like other programs' smoothing.

user541686

Posted 2011-07-22T22:12:09.090

Reputation: 21 330

1

Actually, I think Adobe Reader seems to benefit from the fact that it knows well how to render non clearype fonts (fonts not hinted by utilising Microsoft technology). Most PDF's use professional fonts which are provided by type foundries not using cleartype compatible hinting. Since only Adobe implements the specific rendering for all such professional fonts, Adobe Reader is on top perfectly rendering the smoothing effect.

Rajeev

Posted 2011-07-22T22:12:09.090

Reputation: 11

0

It depends on the PDF.

I uses a variety of PDF readers myself because Acrobat can be a dog loading up on my laptop. I generally haven't seen the same fuzzyness, unless the scan was using a 200dpi. . .

surfasb

Posted 2011-07-22T22:12:09.090

Reputation: 21 453

I don't see how there could be any difference at all with bitmap scans, as you mentioned, while the rendering of the actual PDF typesetting could differ in regards to font rendering, kerning, line-spacing etc. I have not noticed any difference when using Sumatra, but I will start looking and comparing with Adobe Reader more closely. – paradroid – 2011-07-22T22:42:47.023

@paradroid I uploaded screenshots. – Chang – 2011-07-23T02:33:15.387

@Chang: From your screenshots, I can only see differences that may be related to ClearType settings. Have you tried tuning the settings using the Control Panel tool? If you are using XP, you need to install it: http://www.microsoft.com/typography/cleartype/tuner/step1.aspx. However I am not sure if it is possible to adjust how individual programs use ClearType.

– paradroid – 2011-07-23T03:01:15.870

Man, the other one suck pretty bad. Have you tried to force a different font on them? – surfasb – 2011-07-23T04:06:25.500

@paradroid: Are you sure that PDF viewers use ClearType on Windows? I am almost sure that ClearType is used only for Windows font system rendering and I think that no PDF viewer uses Windows font system rendering but I can be wrong. – pabouk – 2014-01-08T08:51:58.333