First, don't worry about the preview settings. They're more for internal use so complex effects play back smoothly. You normally don't want to use them for exporting.
Second, right click on a clip and select New Sequence From Clip. You're good to go. If you still have issues, it may be your system just can't handle the material.
(On a side note, PP doesn't yet support DNxHD in the MXF wrapper, but only as MOV files.)
Thanks for the quick reply! I did as instructed and the playback is basically the same...maybe a 20% improvement, but I'm not even sure.
One thing that gives me pause is when I go to export the files "same as source," it tries to convert them to the codec that the timeline is in, as opposed to exporting them as their native codec. If I do chose DNxHD as the export setting, the render takes a really long time, which makes me think that it's re-compressing all the frames.
Does it seem to you that it might be my system that can't handle the files? That would be very troubling indeed. My 2006 iMac can play 1080p files pretty smoothly so I'm not sure why my PC, which is considerably more powerful, would have trouble with them. My motherboard is almost 6 years old but everything else is fairly new. Do I need to upgrade? More RAM?
when I go to export the files "same as source," it tries to convert them to the codec that the timeline is in
That's why we often recommend you never use that export setting.
With few exceptions, PP will transcode upon export. Everything QuickTime will be transcoded, regardless of changes made. This has to do with the 32 bit nature of the QuickTime API and the 'band-aid' Adobe has to implement to make them work in 64 bit Premiere Pro. (This is one reason I recommend against using anything QuickTime if you can avoid it.)
What are the hardware specs and drive setup of your system?
Motherboard is a Striker Extreme, CPU is an Intel Quad Core 2.4 GHz w/8GB DDR2 RAM. The media is on an internal 500G drive connected via SATA @ 3Gb/s. I'm 99% sure the drive is 7200RPM, but it's been years since I physically looked at it. It was expensive when I bought it 5 years ago, anyway. Video card is Nvidia GeForce GTX 460.
What model processor? For example, Q9660, or i7 920, etc.
Just one drive?
Not 100% sure on the model. I bought it in 2007. If I had to guess it's the Xeon E5-2609.
I have three internal drives: the 500GB I previously mentioned (from 2007), a 1TB purchased in 2010, and my boot/program drive, also from 2010. I believe it's 500GB (I'm not at home right now or I'd verify).
FWIW, I've been doing more tests this week. Moving the project & DNxHD files to the 1TB internal seems to have improved performance slightly, but it still won't play back smoothly in Premiere for longer than 2-3 seconds. The files actually play back considerably worse outside of Premiere (i.e., in the QuickTime player).
Meanwhile, 1080p ProRes422 files play back smoothly in Premiere and in QuickTime. These files are roughly the same size, data-wise, as the DNxHD files.
I'll be editing a feature film in ProRes this summer and I guess I just need to know if I should upgrade my older components.