Many software programs can produce pdf files these days. The Portable Document Format, invented by Adobe, is now so ubiquitous that there’s an ISO standard for it.

The best-known standalone Pdf-creation program is Adobe Acrobat, but coming up fast is Nuance’s PDF Converter Professional, just released in version 4. The program is wisely named, as it converts documents into and from pdfs.

It automatically adds extra toolbars to many popular office programs, such as Word, Outlook, Excel and WordPerfect. Pdf files can then be created from any open document.

An existing pdf file can also be loaded into PDF Converter 4 Professional and converted directly into an editable Word, Excel or WordPerfect document.

This is nothing new, as earlier versions could do the same, but Nuance has reworked its two Assistants – one for pdf creation and the other for conversion – and improved their interfaces.

They're intended for use when dealing with multiple files, which can combine several documents into one.

Two new file formats are supported; the 1.6 version of Adobe's pdf standard and the new PDF/A standard for archival documents.

While working on new formats, Nuance has improved pdf-generation with a new optimiser to reduce file sizes.

To test this, we took an 844K Word file with embedded colour photos and tables and made pdfs using Acrobat Distiller 6, PDF Converter 2 and PDF Converter 4. The resulting files sizes were 802K, 836K and 753K respectively, so PDF Converter 4 wins that one.

The program can read a pdf file to you using RealSpeak, Nuance’s text-to-speech technology. This could be useful for visually impaired owners, but RealSpeak only has one, very American, voice and pays little attention to line breaks or the numbers in numbered lists.

It even managed to pronounce screenshot with an ‘i’ where the ‘o’ should have been.

Improvements in PDF Converter 4 Professional are mostly evolutionary, but they still make it a better product.

The viewer and editor interfaces are compatible and styled for Vista, but some simple editing tasks can still be fiddly.

What should be remembered, though, is that PDF Converter 4 Professional is half the price of Acrobat.

Also consider:
Abbyy PDF Transformer Pro 2
Overall: A good, cheap package for anyone dealing regularly with Pdfs.
Rating: 3/5
Price: £60

Expert PDF Pro 4
Overall: Does the job well and is very cheap compared to others
Rating: 4/5
Price: £40

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