How to Time a Show

Hopefully, I'm not opening a can of worms with this, but I feel the need to add one important exception to John's response.

Most consumer VCR's and DVD players as well as most media file players have time-counters that count hours:min:sec where John's response would be completely correct. If, however, you are using a professional deck with SMPTE timecode, you are actually counting FRAMES and not time (despite what the misnomer "timecode" implies). Another important thing to remember is that the frame rate of NTSC video is not 30 frames per second. It is closer to 29.97 frames per second. What does this mean? It means SMPTE time code actually runs slightly slower than real-time.

So the standard gods created "drop-frame" timecode. The difference here is that once a minute (except every 10th minute) the system will "drop" two frame numbers. (not the frame, mind you, just the number). So the counter goes from 00:00:59:29 to 00:01:00:02.

Does it make a difference? About 4 seconds an hour.

So:

Time Counter = John G. is correct
Drop-Frame SMPTE Timecode = John G. is correct
Standard SMTPE Timecode = last video - cue time - (4sec/hour factor)

As a general rule, if you use smpte time code for show timing - always use drop-frame.

Jonathan Einarsen
Contract Video Specialists, Inc
(A Tightrope Dealer)
www.contractvideo.com

Thank you Both. The question was basically to clarify if cablecast did all the calculations or not. (It does not)

If cablecast were to do the calculations you would enter different numbers.

Actually most of our setup is now digital playback from a server. I kind of wish cablecast did the calc. Just to avoid the math and the occasional oops.

I just returned my Leightronix/Nexus unit after 6 months of use to buy a TRMS Cablecast.
Even the Nexus allowed me to set the new in and out points on a recorded mpeg file. the fact that my SXLE will not allow me to make those edits IN THE CABLECAST APP is really disappointing, B League.

Lance, it's very easy to use MPEG Streamclip for this function. Nice, free app that trims, cuts and appends MPEG files. To me, it's the same amount of time to trim the file in this way. Give it a try, you won't be disappointed!

Streamclip did allow me to trim heads and tails, but scrolling the video player to find the in and out points was typically low-res, hard to control with any accuracy. More importantly, the resulting new program duration does not display at first. One has to save/render the trimmed program, close it and open it back up again to see the new duration. Then, one has to enter that duration in the Cablecast schedule manually.

Another question about Streamclip: is it working in drop frame or ndf? In fact, which is the cablecast mpeg recorder using?

Tightrope needs to build a trimmer right into their software for video recorded on their mpeg recorder that automatically enters the new program length into the program database. (or license a viewer/editor from someone else.)

and they need to be able derive the length of imported mpeg files just by importing them and then insert them into database automatically. Nexus can automatically calculate length, insert in library, and trim heads and tails, although their video player controls were equally hard to scroll and scrub. I figured the TRMS viewer would be better. Imagine my surprise when I found they didn't even have one.
Lance