We give our authors a print copy plus 1 year digital subscription. The comment contributors get the digital copy plus 1 year digital subscription.
Edit: And of course, full and proper credit (Thanks, Peter). The author also gets to link to his/her websites/twitter account in the his/her biography.
I bought this up in comments two issues ago when one of the authors mentioned that they didn't know there was no free PDF issue any longer.
As I said at the time, you should pay contributors at least a token fee to remove any ambiguity about copyright ownership. There is just far too much that can go wrong with the current system, and you are exposing yourself to liability. Saying 'we do pay the writers for their copyright by giving them a free copy of their own content' is not an answer.
I remember when I used to write a monthly column in a computing magazine I would take a monthly salary of $1 simply to remove any ambiguity about ownership. It was company policy not to accept or publish any content that was free (because it never ended up being free).
You are only one pissed off author away from losing everything, or causing a fuss (they could decide to change their mind for the heck of it, a year later).
It would be very different if you were giving a free PDF edition away and charging for a print edition - that is how most open source works (ie. download for free, pay for a CD)
We give our authors a print copy plus 1 year digital subscription. The comment contributors get the digital copy plus 1 year digital subscription.
Edit: And of course, full and proper credit (Thanks, Peter). The author also gets to link to his/her websites/twitter account in the his/her biography.