Live-feed Projection & Recording To miniDV Tape

A

andybiz_2005

Well-known member
Hi friends,

I'm shooting a 3-day Rotary International conference in a day's time, where I am the only videographer. It will be in a hotel's Grand Ballroom that can house about 210 tables, so it's a pretty huge ballroom.

They have asked me to record the three days on miniDV tape for editing later on as well as providing live video feed with my DVX100A camera unto two LCD projectors that will beam the images unto two large screens in front of the ballroom (on each end of the stage).

My question is, if I'm using the Composite connector on my DVX100A (via the RCA - BNC adapter) & connecting the RG-59U Standard Shield PVC Black or White coaxial BNC cable to each of the projectors, can I actually record to miniDV tape simultaneously while the video is live-fed to the two projectors? Do I have to go into the DVX100A's menu options to set up any of the settings to record to miniDV tape & provide live-feed simultaneously?

Since my DVX will be projecting live video footage at all times to the two projectors, does that mean that I cannot press the "REC CHECK" button to preview what I've recorded to miniDV tape? Else the few seconds of recorded footage would be also shown on the screen?

Does that also mean that whatever display options (battery remaining, tape duration, audio levels, zoom & focus settings) will show up on the screen if I don't hide it in my DVX?

I'm sorry to be asking so many questions here as it is the first time I'm recording live-feed. Also, the BNC cables & projectors will be provided. I only need toworry about recording & using my camera for live-feed.

Thanks in advance.

Andrew
 
There should be a menu option that controls whether what's on the viewfinder/LCD is sent out the video outputs. Other than that, I don't believe there's anything special you should have to do to send video and record at the same time.

As for the "REC CHECK" thing, I don't really know. You might want to test that by hooking your DVX up to a TV and trying it. My guess, though, is that yes, whatever you're seeing on the camera is going to be shown up on the screen, so there'd be an interruption in the live feed.
 
You could use the svideo out to the projectors it will look better. if you are feeding 2 projectors you will probably need to find a small DA (distribution Amp to split the signal unless you can loop ) In the manualyou will find the setting to tun off the info on the output. Get them to rent you a DSR45 or similar and that way you can use large format tapes and not end up swapping every 60 minutes together with your in camera vtr. Use the trigger feature in the camera that will allow you to start the second vtr whenyour incamera tape is about to run out. get a comfy chair.
 
thanks Captian & Murphy for your helpful comments. Murphy, what exactly do you mean by looping the signal? How do you do it? Thanks.

Andrew
 
Some projectors have both an input and an output; "looping" refers to running your signal out of the camera to the first projector's input, then running out of its output to the second projector. There aren't a lot of projectors with video outputs left, though--those were one of the first casualties of the drive to make projectors smaller & cheaper. :)

And, at least in my experience, composite video is easier to work with on long runs, if only because my shop doesn't stock a lot of long S-video cables. :D IMO, you don't gain much with S-video over composite once the signal is blown up to 9x12' or some other large screen size anyway...
 
Thanks for responding Captain. I was out shooting this evening. You are right re looping and s video, but sometimes every little bit helps.Andy find youself a cheap Dist Amp for comp and you will be fine.
 
I too would recomend Composite.
It's not so much the signal type that matters with these long runs, but the quality of the cables. And good composite cable (RG-59) is much easier ot come by than good S-video cables (two RG-59's running parallel is the only option for long runs)
Use Black cable, it's generally more flexible and "camera friendly" then the white stuff.

The Composite output on the camera will send out teh same video feed that yous ee on yoru LCD. Live any tiem the camera is on, or playback during VTR mode or a "Rec-check". Use your menu to turn off the on-screen data overlay off the composite outputs. - Test all this at home untill you understand it all with your eyes closed, it will be important in a live situation.

If at all possible, get a video mixer - anything, no matter how small - in between the camera and projectors so that you can fade/cut yrou feed to black. Before & after the event, during tape or battery changes, are all times that yoru audience does not need to (shouldn't!) see your camera feed. Maybe hook up a DVD player with a looping logo of the client's choosing to display when your camera is in black. Even if you have to walk back to the mixer yourself (if you are roaming), it will be worth it. Better yet, get a buddy on the end of a 2-way radio to hit the fade for you when you need it. Or if you are creative, use a RF remote control to a GPI input on a video mixer to hit the fade for you.

- Mikko
 
Thank all & esp. Mikko for pointing me in the right direction. Tomorrow I'm gonna get the RCA-Composite BNC connector before the shoot so that I can fit it to the composite port of my DVX. At least the BNC cable & projectors will be provided by another vendor. So I just need to provide the camera & cameraman (me ofcourse). Mikko, unfortunately, there will be no switcher around b.c. of the client's budget constraints. So whereever I shoot, I need to be concious of a steady hand & not pan too much. Sure, I'll be shooting from a tripod as much as possible.

But I don't know how to handle the tape change, as there is no switcher unit. So the screen will have to go blank momentarily while I switch tapes. Are there any settings in the camera's menus that I have to select so that I can record to miniDV tape what I shoot & simultaneously broadcast the video live to projectors? Or is it just as easy as pointing & pressing the record button to record to miniDV tape & broadcast live at the same time?
 
I don't think the screen will go blank while you change tapes--it'll just be on a static image, because you'll be too busy to do any panning or anything else. :) Something to keep in mind as your tape gets toward the end--you might want to pull out to a wider shot, so you don't lose the speaker if he's a wanderer.

And it should be just that easy.
 
OK thanks captain pierce, I'll keep that in mind while switching tapes. Hope all goes well, cause the shoot starts today evening.
 
Hope it goes (or by this point, went :) ) well.

Something to keep in mind for next time: a good (and fairly inexpensive) way to back up a long show like this, BTW, is a DVD recorder with a hard drive built in. You're already (hopefully) getting a feed from the sound board for the tapes, so all you have to do is take the S-video and audio outputs and plug them into the recorder. The only outputs on these units are typically analog, but with they right hardware, they can still capture into a computer at fairly good quality. Cheaper than a Firestore, and with longer record times as well (a 120GB unit can hold something like 30 hours at its highest quality setting).
 
I'm glad to let you know that the 3-day convention shoot went well with the live-feed to the 2 projectors a success. The IT guy who set up the projectors & provided the composite cables for the live feed told me that he used a small box the size of a ADSL modem that had 5 buttons on it. One button was connected to a DVD player where if he pressed it, there would be a looping logo, another button would show a multimedia powerpoint presentation from a laptop computer & the third button for the live feed from my camera. And yes Mikko, the composite cable used for the live-feed was the high-quality (RG-59) one you mentioned earlier.

What puzzled me was that the 2 LCD projectors at the convention could not produce a bright enough image on the screens, even though my camera's viewfinder showed me that exposure was just right (not to dark). I noted the brand of the projector to be a Sanyo. I doubt it was a DLP projector as I know that LCD projectors generally have higher ANSI contrast than DLP projectors. The projected images came out looking quite dark with the darker parts of the image being unable to hold it's resolution. It was just a blurry black image. Perhaps the projectors were put on low-contrast setting to extend the life of the bulb.
 
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Actually, Andy, it's the other way around--DLP typically has higher contrast (and FYI, it's not "ANSI contrast," just contrast) than LCD. What you're talking about is brightness, not contrast, which is measured in ANSI lumens. This is something where LCD and DLP are essentially equal, neither has a brightness edge--as long as you're willing to pay for the level of brightness that you need. :) More lumens = more money. It's possible that they were on a lower brightness setting to extend lamp life, but it's equally possible that they just didn't have enough horsepower for the gig: either the screens were too big, or there was too much ambient light in the room, or any combination of the above plus a couple of other possible factors.
 
Good to hear that the shoot went well.

Also good to hear that they had a switcher in line for you - you understand it's importance now. :)

The "dark" picture on the projectors could be a number of things.
The projectors may have been too weak, or improperly set up (as mentioned above)
The ambient light may have been too bright on the screen, which is related to the above.
It's possible that the signal was not distributed properly to the projectors. I don't know what the "little box" was doing in addition to switching, but if the video signal was split without amplification, it could have been double-terminated, resulting in a dark image.
- All of the above would probably have been equal for all the sources; DVD, PC and your camera.
It is also possible that your camera had "Setup" "Off". This makes for a slightly (7.5%) darker signal. The down side is that you should have Setup OFF for recording to DV, but On for a live output. Not much that can be done for this shoot.
The only correct solution would be to leave it off (so it records properly) and have a external TBC (another little black box) to add Setup to the signal.

Sounds like it was a success though! :thumbsup:

- Mikko
 
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