QLAB Black Flash

[Roddy Armory Theatre]

I am setting up the projections of the Addams' Family using QLAB. I have a problem with auto-follow, though: several of the cues have a black flash when they begin. Here is a video of the problem (the flash happens at 8.2 seconds):

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[Roddy Armory Theatre]

Extra Information:

Running a mid-2010 21.5 inch iMac with a 3.6 GHz Intel Core i5, 4GB DDR3 RAM, and ATI Radeon HD 5670 graphics (512 MB)

QLAB Version 4.0.7

 

[ruinexplorer]

That looks like a dropped frame. Is the input (video clip) set to the same frame rate as the output?

 

[Amiers]

Does it happen outside of QLAB?

 

[NickVon]

Did you get the video components from Broadway Motion Design. It looks like there file naming convention. (Now called something different I think). I did a production of Marry Poppins using their video package. and had similar issues on just a couple of the cues. If I recall, I actually encountered it when linking a "static/looping" clip to one of there "Fade out clips." BMD should be your first call though, you should have an account rep for your 'rental' that should be able to address this. Let us know how you make out.

 

[Malabaristo]

You may want to try adjusting the start or end times of the cues by a frame or two. I had a similar problem with a video that I wanted to hold at the end: QLab didn't like the last frame in the file for some reason, but the next-to-last was fine (...possibly for a valid reason, I just didn't take the time to figure that out exactly since the quick fix worked). It's hard to tell whether what you're seeing is the end of the first cue or the start of the second.

 

[sk8rsdad]

Yet another trick is to layer each video on top of the last with an opacity of 100%, then delay the fade of the bottom layer to the cue following the active one. That way the outgoing cue doesn't contribute anything odd to the fade in of the incoming cue.

 

[Jay Ashworth]

Are you cutting from a static cue to a cue with a fade baked into it?

Adjust the relevant out and in points; you may be cutting too early (or late).

 

[Roddy Armory Theatre]

Thanks to all who replied. I have contacted BMD and they are supposed to have a technician call me. None of the video files have a black frame at their beginning or end. I have already tried adjusting the timing (as Malabaristo suggested), but the flash is still visible. Sk8rsdad, I will try your suggestion in the next few days and let you know if it works. Jay, the flash happens just as NickVon described his similar issue: in between loop and fade clips. ruinexplorer, I will also check the frame rate.

Thanks!

 

[Jay Ashworth]

Oh, you're coming out of a loop?

Yeah, that sounds like a bug.

 

[Tamas Nagy]

Could be a QLab bug too. Make sure you are running the latest version. Also worth to drop an e-mail to the QLab guys if you didn't already do.