Is 720 50P more prone to error????

[Chris Harding]

Hi Guys
I just had a harrowing issue with Vegas 10e crashing on project load only to eventually find that I had a faulty video clip!!! (it took a LONG process of elimination to find the problem as it has never cropped up before now!! I shot this commercial project at 720 50P  (60P for you USA guys!!) I copied the file from the card a second time and the project now loads without an error but I'm not yet sure if it is a poor card write or just a copy to drive problem??
Does anyone know if double frame rate progressive footage has a higher corruption or copy error rate than interlaced footage ... I have a wedding shoot in the morning here and don't really want to chance something that might do the same thing especially with a wedding where a re-shoot is impossible!!!  All my other weddings were shot in 1080i as well as all my Realty shoots too and never a problem!!! Does the camera card have to work a lot harder when recording in a double frame rate at 24 mbps or does shooting in 1080i have a "lower" write speed and less likely to have an error???
Chris

[Digidave]

Hi Chris,

I think you answered your own question, double the frame rate = double the amount of data so yes, the card does have to work a lot harder.

Dave

[Chris Harding]

Hey Dave
That's what I was figuring too!! I didn't actually have a bad card write it just didn't copy across to the drive correctly!!!
Chris

[Guy Bruner]

Let's look at this more closely.  If the frame rate actually doubles, the data rate doubles as well.  However, in PH mode the data rate stays the same at 21 Mbps average no matter if you are shooting interlaced or progressive.  It is the data rate that is important to the card speed and, if higher than the card can accommodate, the clips on the card can become corrupted.

Remember, we are storing the same amount of data in interlaced and progressive modes.  One complete frame is still 1920x1080 or 1080x720...same amount of bits in both interlaced and progressive modes...only split into two fields in interlaced mode.

Chris, if you copied the clip and it was okay a second time, the likelihood of it being corrupted on the card are low.  Something happened during capture.  In my experience, Vegas is pretty robust and very seldom crashes.  I'd suspect something going on outside of the program.

[Chris Harding]

Thanks Guy
I was actually very surprised that a bad media file would crash Vegas 10!!!  One would expect the program to reject the media as unsuitable/not able to import etc etc but it actually creates a kernal error in Windows and Vegas stops dead!!!  I wonder if the older versions would also crash with bad media or even wrong media?
Chris
 

[Guy Bruner]

I don't recall getting a lot of crashes in Vegas.  Back when we were importing DV from tape, sometimes I would get dropouts, but Vegas chugged right on.  It would sometimes stop if there was a gap between two clips, but it never crashed as I recall.

[Chris Harding]

Hi Guy
It was most definately a bad copy from card to drive. As nothing was affected until Vegas attempted to play the clip in the time and it was a kernal error seems to point to a codec crash which would indeed occur within the kernal system when faced with a corrupt file!!  I always keep the cards intact until an edit is complete simply as a backup!!  It's all good now and I learnt something too!!!
I actually shot yesterday's wedding at 1080i and not 720 50P and I truly cannot see what the big deal about 720 50P is all about. The footage at 1080i looks just as good to me and if the difference is there it must be technical and not visual!!! 
Hope the nasty weather is not affecting anyone here too much!!!
Chris

[Guy Bruner]

Yes, continuing to learn is a good thing!  Progressive footage is particularly useful for fast motion shooting.  Usually, there is not much of that in a wedding until the bride and groom exit the ceremony.  Also, progressive frames can be turned into pretty good still photos...