You can use your four downloads at any time up to a year from purchase. Your initial download does not count toward the four allowed. As time goes by the book will be updated, so you can choose which updates you retrieve and which you ignore. I'll be sending out emails to people who have links that are about to expire so you can get the most up to date edition at that time.

Aperture 2.0 has been released. The current book is no longer available. Existing customers can download the third edition that includes the final articles I wrote about Aperture 1.5 When I have enough material for a Get Your head Around Aperture 2.0 book, current customers will get it for free.

Email me and I'll fix it.

I plan on updating the book every month or two, roughly. I will roll up all the material added to the blog over that month and update the ZIPped package of PDFs. You'll know that an update has occurred in one of three ways:

• I'll announce it on the blog
• The publication history page will be updated with details
• I'll send an email to everyone who has purchased the book

At the very end of the book is a colophon. In the colophon is a table of publication history. Yours is the latest listed in the table in your book. For example, here is how the publication history looked after the first edition was published:
You can find out what the current edition is, and what has been changed by looking at the publication history page.

When you buy the book you get your own personal download link and a code. You click on the download link to retrieve later editions of the book -- up to four -- over a one year period. The code plays no part in the download process. The code is your proof of purchase and may be used in the future.

Mark your calendar! I will be emailing people in advance of the expiration of their year to let them know that they may want to get the latest edition soon.

When you originally purchased the book and completed the purchase it was downloaded automatically. You also received an email with a download link and a code. To download an update to the book, click on the link again. Each click counts toward your four allowed updates, so be careful. The code is your proof of purchase.

Email me. I don't have an automated way of giving this information.

Not at this time. If there is enough demand I may offer a printed version. But a printed version will cost more, will take longer to deliver, and will have to be bought all over again in order to include newer articles.

You can print the PDFs you receive on your own printer. Two of the PDFs in the package are optimized for printing, one on A4 paper and one on US Letter paper.

Select the edition you want to print according to the paper size you are using (both an A4 and a US Letter edition are provided in the download) and open it with a PDF reader. Print it as you would any other document. You may want to avoid printing the cover page because it will use up a great deal of black ink or toner.

I do not recommend uploading it to a print-on-demand service like Lulu. I have never tried this. I also know that the PDF output by Pages is not suitable for the printing systems used by these services because of the way it handles transparency and fonts.