Time for a fresh look
Last March we reviewed a crop of free PDF readers available for Windows. This time, we add a new contender to the list (Nitro’s PDF Reader) and check for updates to the software reviewed in our previous survey.
Bloatware? Really?
It’s a sad fact that the quality of PDF files varies widely. The original specification (the PDF Reference) was published in 1993, and left a lot to the imagination. The Reference has matured enormously since then, but a lot of PDF creation and manipulation software was written when the Reference was less specific than it is today.
Aggravating the problem, developers have no independent validator for PDF, so many took the easy way out. If their software was able to make PDF files “good enough for Adobe Reader”, then it was “good enough”.
Low-quality software means broken, huge or slow PDFs that clog computers, drives and software.
If a Reader (any Reader) is taking a long time or chokes when opening a PDF, there’s usually something wrong with the file, not with your software.
Demand “ISO 32000 conformance”
Poorly constructed, inefficient PDF is here now, and it won’t go away until consumers demand PDF creation software that meets the latest International Standard for PDF, specifically, ISO 32000-1:2008 (and the forthcoming ISO 32000-2).
The big news, of course, is the release of Adobe’s Reader X, the 10th generation PDF viewer from the company that started it all. Reader X is a significant improvement, including new (from Adobe) features previously reserved for the paid Adobe Acrobat. It’s not an idle move on Adobe’s part – the competition is accelerating.
I’ve discussed this issue of “bloatware” before, and thus won’t dwell on it too much this time. Simply put, one need not worry whether ABC software has a 5 MB or a 50 MB installer, or takes 20 or 200 MB of HD space, or consumes 30 or 50 or 100 MB of RAM when running.
Safari and Netscape readily soak up 500 MB of RAM at the drop of a hat, 5x more memory than the ‘heaviest’ PDF Reader on its worst day. Bottom line: the only thing worth ranting about is performance.
I’m happy if it’s just fast, safe and reliable. Aren’t you?
How we reviewed, what we looked for
The selection of Readers is not intended to be definitive. We are open to adding new PDF viewers as they become available. If you feel we’re missing an important new option, please feel free to leave a comment, and we’ll consider it for the next review.
As in the previous round-up, we’re not focusing on marquee features decorating various marketing materials. This review focuses on real-world performance in key line-of-business functions. The point is to find out whether or not these applications were ready for prime time, comparing them to the application that remains the de facto standard for PDF viewing: Adobe’s Reader.
All tests were performed on Windows XP. This may seem slightly “retro”, but the reality is that Windows XP is still far-and-away the most commonplace desktop operating system right now – and performance in the real-world is what this review is all about.
Let’s meet the contestants
Adobe Reader X: Now in version 10, the latest user interface is minimalist, almost muted, maximizing the space dedicated to the document. A new “Read Mode” makes it even more so. Adobe Reader’s strength remains, as ever, in the “under the hood” capabilities and attention to detail. The new Protected Mode (“Sandbox”) will appeal to any IT department. One certainly hopes this new security architecture will mean fewer encounters with the dreaded Adobe Updater and atrocious Download Manager. Why is it that companies three orders of magnitude smaller than Adobe can get a simple installer done right, but Adobe cannot? Download Adobe Reader X
Foxit Reader: Determined to be the lightweight alternative to Adobe, the latest update to Foxit’s Reader does indeed “weigh” the least; under 6 MB to download and consuming less than 20 MB of RAM when running. Foxit’s Reader has improved significantly since we last reviewed it in March, 2010, especially in support for forms and annotations. It seems more stable as well, even if it still can’t handle some broken PDF files the way Adobe Reader can. This software earns the prize for most improved since the last review. Download Foxit Reader
Tracker’s PDF-XChange Viewer: The draw with Tracker’s Viewer are lots and lots of annotation tools, even links. The only exception in terms of annotations are file attachments, which requires the paid Pro version, and the audio commenting tool, which doesn’t appear to be available at all. After applying annotations or images, the user can flatten the file. One problem that definitely needs an early fix – the Viewer reported a certified PDF as valid after I’d just finished carefully invalidating it! Oops! On the other hand, Tracker is making strides with their support for XFA forms. Download Tracker Software’s PDF-XChange Viewer
Nuance’s PDF Reader: The Nuance Reader offers a number of capabilities that stand out from the rest of the non-Adobe crowd, differences intended to appeal to corporate users. For one thing, Nuance has the best support for Acrobat Forms, JavaScript and XFA forms outside of Adobe’s own Reader. The app includes SharePoint integration and once started, opens PDF files about as fast as Adobe’s Reader. On the down side, support for annotations is limited, the application has no onboard facility to export document text, gets digital signatures wrong and like the other non-Adobe apps, seems entirely unaware of both PDF/A and tags. Download Nuance’s PDF Reader
Nitro Software’s PDF Reader: This software sports an easy-to-read user-interface inspired by Microsoft’s “ribbon”. Nitro is well-rounded, with important features in several areas, the stamp signature tool is especially functional and intuitive. Most users are (understandably) intimidated by real digital signatures, so if stamping an image onto the page works for you instead, you’ll like Nitro. When it comes to copying text for extraction, Nitro’s Reader doesn’t accept PDF reading order as gospel (as do the others), but actively interprets each page. Support for tags would be better, but at least they are thinking about it. Download Nitro Software’s PDF Reader
While free, Apple’s Preview is not covered here. Yes, Preview can display (most) PDFs. Yes, it’s already on your Mac and it’s the default PDF viewer on that platform. Obviously, it’s less of a “hassle” – from that perspective, anyhow. So why isn’t it in this round-up?
- Preview is so profoundly broken when it comes to saving PDF files that I refuse to review it until Apple bothers to download, read and at least begin to implement ISO 32000. Unlike the relatively tiny companies offering most of the Adobe-alternative PDF readers, Apple can afford to do the right thing at any time, but chooses not to. Don’t Mac users deserve software that doesn’t trash a PDF? Read this article if you want to learn more.
- For now, we’re covering only 32-bit Windows software because that’s what the vast majority of the world uses. We’ll consider expanding the scope to other operating systems when issue (1), above, goes away.
A Fistful of Readers
Notes on each feature reviewed follow the table.
Basic Statistics
Intentionally blank | Adobe Systems | Foxit | Tracker Software | Nuance | Nitro Software |
---|---|---|---|---|---|
Available OS | Win / Mac / Linux | Windows only | Windows only | Windows only | Windows only |
Release tested | v10.0 | v4.3.0.1110 | v2.5.188 | v6.0 | v1.3.1.1 |
Download | 47 MB | 5.6 MB | 13.8 MB | 18.6 MB | 26 MB |
Installed | 106 MB | 13 MB | 31 MB | 44 MB | 61 MB |
RAM | 38 MB | 19 MB | 35 MB | 40 MB | 78 MB |
Performance
Intentionally blank | Adobe Systems | Foxit | Tracker Software | Nuance | Nitro Software |
---|---|---|---|---|---|
Cold start | 2.3 secs | 3.1 secs | 9.1 secs | 11.3 secs | 7.4 secs |
Warm start | 1.9 secs | 2.7 secs | 3.7 secs | 6.4 secs | 3.9 secs |
Open file | 0.6 secs | 0.9 secs | 1.3 secs | 0.6 secs | 1.0 secs |
Open big file | 1.6 secs | 1.8 secs | 2.2 secs | 0.9 secs | 4.3 secs |
Core Functions (selected)
Intentionally blank | Adobe Systems | Foxit | Tracker Software | Nuance | Nitro Software |
---|---|---|---|---|---|
Open options | Correct | Correct | Errors | Correct | Error |
Digital signatures | Full support | Errors | Errors | Errors | No verification |
PDF/A awareness | Conforming | Unaware | Unaware | Unaware | Unaware |
Annotations & Stamping
Intentionally blank | Adobe Systems | Foxit | Tracker Software | Nuance | Nitro Software |
---|---|---|---|---|---|
Annotations | Add 2 types | Most types | Most types | Add 3 types | Add 3 types |
Functionality | Incomplete* | All | All | Incomplete* | All |
Stamping | – | – | Flattener | – | Image stamper |
Fillable Forms
Intentionally blank | Adobe Systems | Foxit | Tracker Software | Nuance | Nitro Software |
---|---|---|---|---|---|
Simple Form | Ok | Almost there!** | Fail | Ok | Ok |
Complex Form | Ok | Almost there!** | Fail | Almost there! | Fail |
Save Form | Need Extensions | Yes! | Yes! | Yes! | Yes! |
XFA support | Static & Dynamic | No | Improving! | Almost there! | No |
Acrobat JS | Complete | Incomplete | Incomplete | Incomplete | Incomplete |
Reuse and Accessibility
Intentionally blank | Adobe Systems | Foxit | Tracker Software | Nuance | Nitro Software |
---|---|---|---|---|---|
Reads Tags | Yes | No | No | No | No |
Export Text | Tags | Interprets page | – | -*** | Interprets page |
Copy Text | Interprets page | “Reading Order” | “Reading Order” | “Reading Order” | Interprets page |
Review Notes: Size Matters, or Does It?
To put the question of “bloatware” in context, we recorded typical “bloat” metrics for all applications, specifically:
- The installer size for each application as downloaded.
- The installed size of each application (ie, the total size of the files installed into the /Program Files folder)
- The RAM consumed by each application (each app had the same PDF open for this test).
Look over these numbers, then compare with application performance.
You be the judge. Does size really matter?
Performance
This 1018 page PDF (one version of the US House’s Health Care Reform legislation) was used for the main speed tests. Default settings did not include thumbnails (since they add a lot of time). The timekeeping was manual; your mileage may vary.
The cold start speed is the average of three trials following a system restart. This speed will typically be encountered only the first time an application is opened after a system restart.
The warm start speed is the average of nine trials (actually, ten trials with the outlier eliminated before averaging). This approximates the performance encountered when re-opening the application between restarts.
For the open file speed test, the application is already running, so we can focus on the time required to simply open the PDF. This figure is also the average of nine trials (after one outlier result was rejected).
The “open big file” test was conducted on a press-ready PDF, in this case, a 525 MB, 244 page file created in Quark. The file includes tons of fonts, vectors, images, you name it. This figure is the average of four trials, after one outlier was rejected. For obvious reasons, I’m NOT posting the file – you’ll just have to trust me!
Open Options
Not all viewers respect every possible setting in PDF files with respect to the display of bookmarks, thumbnails, magnification, initial page number, toolbar display and other so-called “open file options” that may be set by a document author.
A PDF viewer must be able to display the document as the author intended. Bookmarks and thumbnails are vital usability features for longer documents, and other file option options (2-up display, or initial zoom level, for example) are important as well. These settings aren’t new to PDF; this is a fairly basic area of functionality, and all prime-time PDF readers should get this right.
We tested each Reader in this survey to find out if they respected five possible non-default settings. Two Readers showed one error apiece: Tracker’s Viewer failed to display the bookmarks and Nitro’s Reader failed to hide its toolbar. We will probably perform an exhaustive test of the Open Options features in the next survey, so developers are hereby warned!
Signed and Certified PDFs
Using each Reader in turn, we attempted to open this PDF file (the US Budget for 2011, 7.7 MB), a GPO-certified (ie, digitally signed and secured) PDF. We then noted the differences in behavior.
“Full Support” means that the reader notified the user of a digital signature, accurately reported its status and provided a means to validate the signature (or certificate).
“No verification” means that the reader was aware the PDF was signed, knew the signature was valid or invalid, but was unable to verify an otherwise verifiable signature.
“Error(s)” means that the reader stated that a valid and verifiable (by Adobe Reader) certificate was nonetheless invalid and/or reported an invalid certificate as valid. This is most certainly not the desired result.
Support for PDF/A
The archive subset of PDF is ISO 19005, better known as PDF/A, is the standard for long-term preservation of electronic documents. Published in 2005, PDF/A is being adopted by governments, courts and businesses around the world as a key part of their information retention strategy.
PDF/A includes “conforming viewer” requirements, which Adobe presently over-interprets to mean “read only”. Quibbles about how to implement “PDF/A mode” are one thing, but only one application (Adobe’s) appeared to even notice when a PDF/A-flagged file is opened!
Software developers should be sure to follow best practice when implementing any International Standard, and PDF/A is no exception. This article offers guidance on developing software to work with PDF/A files.
At this point, it’s fairly inexcusable for desktop PDF readers to simply ignore the PDF/A flag, but all the Adobe-alternatives still do precisely that. C’mon, developers; you can at least read the XMP and show a flag, even if you aren’t validating for PDF/A compliance!
Annotations & Stamping
The test file is a simple PDF that includes one example of each type of standard PDF annotation.
While there are many powerful annotation features in Acrobat and Adobe Reader, a competing PDF Reader, minimally, must be able to properly display standard annotations added by other software.
To gain an advantage over the 800 pound gorilla, Adobe’s competition has spent a lot of time and effort on providing annotation creation features in their free Readers. In Reader X, Adobe strikes back, for the first time adding Notes and Highlighter tools to Reader without requiring Reader Extensions.
Inexplicably, however, Adobe chose to drop some of the standard functionality for Notes created in Reader X; you can’t reply to a Note in Reader unless (you guessed it) the PDF is Reader Extensions-enabled! This earns Adobe an “Incomplete”.
Only two applications in the review, Tracker’s Viewer and Nitro’s Reader, offered any type of stamping – the addition of text or images directly to the PDF page. This is a powerful feature, and we expect to see it cleverly implemented in future versions of these increasingly assertive “Readers”.
* – Only two applications, Adobe’s Reader X (as noted above) and Nuance’s Reader, are unable to reply to an annotation. On the other hand, Nuance’s Reader was the only non-Adobe application to successfully play an audio annotation (my personal favorite).
Forms
We attempted to open a few of our customer’s forms with each viewer and noted the results.
“Simple” forms – standard Acrobat forms (Acroforms) including only basic calculations and validation.
“Complex” forms – standard Acrobat forms including field-properties formatting and other advanced Acrobat JavaScript methods and techniques.
Both static and dynamic XFA forms were tested. Adobe’s Reader handled the XFA with aplomb (as expected). Nuance’s Reader did a credible job on XFA forms of both types. Tracker’s been working on XFA as well; while we saw problems we also saw a lot of progress.
** – Of the non-Adobe PDF Readers, Foxit showed promise in terms of improved support for advanced PDF forms and Acrobat JavaScript functionality. BUT – we still (as in the previous review of this software) saw some errors when rendering (displaying) forms including blacked-out form-fields.
Reuse (exporting text & accessibility)
There’s something a lot of people want “out of” PDF files, and that thing is text. PDF are internally complex, and most lack the structure (known as “tags”) necessary for reliable results when exporting text. Worse still, few Readers even bother with tags.
For this test, we extract text from a PDF using two different methods. In one case, we export the entire document; in the other, we select some text on a page with the mouse, copy, then paste into Notepad. The document is correctly tagged, but the content stream’s reading order differs from the tag order, allowing us to determine how each Reader goes about generating usable text.
Reads Tags: Users who rely on assistive technology require properly tagged files in order to read. Only PDF Readers capable of reading PDF tags can comply with Section 508 regulations regarding accessibility.
Export Text: Only Adobe Reader uses tags when exporting text. Two competing Readers (Foxit and Nitro) ignored the tags but include software that interprets the page, attempting, in effect, to tag it “on the fly”. Results are guaranteed to vary.
Copy & Paste: None of the applications use tags to support copy and paste; and Adobe and Nitro add some some interpretation to the raw “reading order”. Page interpretation will give better results than blindly following the content-stream in many cases, but both are poor substitutes for tags.
*** – The Nuance Reader does not include an option to export document text. It requires the user to upload their file to Nuance’s servers for processing, which involves providing an email address. I dutifully tried this, only to learn that their servers “couldn’t convert” the same file the other free Readers were converting right there on my desktop – that’s a #fail!