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weak video assist signal-inline gain unit?


Thomas English

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pop an sr2 on... put a little t-bar bnc to split the signal from the dusty video assist (one to TX and one to sled). let AC screw the aperture down and hey presto--- dark monitor (panasonic lcd) real dark... then the film rolls and well your steadicaming blind. frantically try and turn the gain to maximum.. open up the assist aperture... no joy.. both wide. where are the mice?....

 

apart from battling with mild stupidness... am i also missing something?

 

can anybody recomend an inline 12v gain unit i could pop before the monitor? can anybody recomend a 12v signal booster for before the t-bar? im sure these are things that are built into the Marell etc monitors but i cant afford em so i reckon i should be able to get seperate units.............

 

i mean a high gain CRT monitor... is a normall CRT monitor with a good gain module before it?.................. i want a gain module........

 

do i? :ph34r:

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Video Accessory Corp. (vac-brick.com) makes video DAs that work off 12-32v power. They also make 12v only versions. They have about 30 variations in different sizes, some with multiple outputs (2,4 or 8) and options for individual gain control per output (less for your monitor, more for your transmitter, etc.), plus some simple economy models and some slimmed down units that you could squeeze into your junction box or electronics base. Try vac-brick.com or call 800-821-0426. Markertek.com is a distributor.

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I had the same experience with an SL, the other day. Not that it´s video-assist is so bad, but when they start shooting on 500ASA and push one stop, there is just not enough to work with......

So I quickly put together a +30Db video amplifier between the assist and the video-input of the sled ( I happened to have one print ready (?25))(not between the sled and the LCD because you will overload it with the framelinegenerator that is always 100%) and I could see at least where my actors were. But forget about other stuff, like stands or coffeecups in the background, no way you can see them in this case.

 

Rob van Gelder, Bangkok, Thailand

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I had a simillar problem recently with two Panavision 16mm camera that had a terible video assist. When we were shooting WFO, video assist gain boosted to the top, all detail was gone once the film was rolling, only basic shapes were visible. Even with Greg's fantastic TB-6 adjusted the best I could I still had difficulty. What is out there to help alieviate this problem besides more light?

Ari Gertler

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25 euro DistributionAmp? cool, is that bought in thailand though?

 

putting the amp before the sled... is that because a little signal gets lost in the sled? if i don have a frameline gen it should be fine? oooooo i see... is your frameline generator inside your sled?...... must be. so signal boost before and frameline generator or xcs level indicator or anything else that puts a signal on.

 

i guesse the problem is in the cheap ccd s ... my next sr2 shoot is on saturday and is at 120fps ... so i reckon the problem will be loads worse? seeing as the shutter shutting is half the dark problem.... hopefully one of these 120ukpound units mitch recomended me will do the trick

 

30db ey? thats loads.............

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No, the amp is bought and made in Holland, as a DIY board, with 1 input and 5 outputs and realy heats up the video signal.

That, said, it also heats up all the noise fron the camera motor so it doesn´t always work as expected.

I just looked back on my little DV recorder and it´s amazing that I managed to make the shots: in a blackened dockyard at night.

 

 

Rob van Gelder, Bangkok, Thailand

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Dear everybody,

 

I read this post and thought about the next option?

Didn't anyone think of the consumer option on a DVcamera to switch it to NIGHT SHOT mode? Must be a way to make a video assist unit work with the same feature? (E.G. Lenses stopped down with ND polafilters, low light levels, high speed camera's )

 

Kind regards,

 

 

Patrick van Weeren

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Not onlu the beamsplitter could make things worse, also the frame rate on most cameras goes down, in order to create a higher sensitivity. So You can have something like 15 FPSlooking ar a groundglass of a 24/25/30 fps camera

I´m not sure that is good and it will also introduce streaks and faded edges on moving objects. A least that is wat my very small Canon MV5 makes of it in low light or night mode.

But I will give it a try on of these days.

 

Rob van Gelder, Bangkok, Thailand

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