This might be a really dumb question, but why is it that my 8 gig cards always record only 28 minutes regardless of the recording quality setting? Why wouldn't the file sizes drop somewhat when I use the lowest quality setting on my EX1?

When using 1080/50i sp (25 mbs) my 8gb cards give me 39 mins.
Your 1080/60i sp should give you the same.
1080i sp is the only format which is 25mbs, all the rest are 35mbs, hence the lower recording times.

Paul.

Indeed, what Paul said. The 720p modes are all high quality, designated by the HQ next to the name. The 1080/60i and 1080/24p SP modes are the lower data rate settings.

Dave, I strongly suggest you obtain a PDF copy of Phil Hodgett's The HD Survival Handbook.

http://www.proappstips.com/HDSurvivalHandbook/

It is the most impressive run-down of all the whys and wherefors of HD video, written for the rest of us in clean but easy to understand terms with excellent illustrations and references to specific gear.

It's only $15.95, and 212 pages, 54 Megs. Please be advised that I have no financial stake in providing this information. It's simply a matter of spreading knowledge where it can be the most helpful.

The following is from the Foreword:

"The HD Survival Handbook was written to answer the myriad of questions that arise when a video professional moves from working in the Standard Definition world up to the more complex world of High Definition.

There is a companion blog site for this handbook at http://blog.proappstips.com/archives/category/hd-survival where updates and changes will be posted.

The Production section of the Handbook covers the reasons why you should be working in HD, how to interpret specifications, HD formats and a direct comparison of HD Cameras under US$10,000. The Post Production section has everything you need to know to deal with HD through a Final Cut Pro edit, including storage requirements and technologies, capture hardware, HD workflows, 24P pitfalls and workflows, and finishes with archiving file based media.

The Distribution section of the Handbook covers the issues of distributing HD when
the production is complete."

Or in handy DVD form, I humbly offer our training disc. :)

http://www.callboxlive.com/store/sony-guidebook-p-39.html

-Noah