The above Ad will no longer appear after you Sign Up for Free!

200' or more, from camera to projector...What's my best option?

Discussion in 'Multimedia, Projection, and Show Control' started by SjonRokz4u, Apr 23, 2009.

  1. SjonRokz4u

    SjonRokz4u Member

    Messages:
    26
    Likes Received:
    0
    Thanks in advance everyone.
    Im supplying a PA system for this show already. Now theyve asked for an 8x8 screen (rear projetion) a projector and live 1 cam to the projector for the length of the show. My problem is this could easily be 200' or more. How should I get my video back to the projector. Cam is an old JVC GYDV500 it has composite bnc and firewire outs. I dont know if its possible but there will be an audio (xlr) snake there with a couple of extra returns available. Otherwise Im looking for my best cost effective methodusing cables and adaptors. Also B and H suggested something called a banus or like word. This will be my 1st show with a projector and screen so Im open to any and all suggestions. If it helds, the projector is a Hitachi cx417 I believe, has allconnections but BNC...............Thanks!!
     
  2. derekleffew

    derekleffew Resident Curmudgeon Senior Team Premium Member

    Messages:
    4,506
    Likes Received:
    2,926
    Location:
    Las Vegas, NV, USA
  3. doctrjohn

    doctrjohn Active Member

    Messages:
    178
    Likes Received:
    24
    Occupation:
    Theater Technician
    Location:
    Madison WI
    B&H probably suggested video baluns. They are either active or passive devices to allow you to send video (or audio, or USB,etc...) down a piece of CAT5 wire. This is one example for composite video. These can be incredibly useful devices, but keep in mind that CAT5 cable is very fragile and you probably wouldn't want to run it/treat it like an audio snake cable. There are manufacturers who make robust CAT5 cable, but it is not cheap.

    Good luck with your show.

    Best,
    John
     
  4. NickJones

    NickJones Active Member

    Messages:
    950
    Likes Received:
    59
    Location:
    Somewhere far far away, Vic, Aus
    Yeah, as John said, you can run it through Cat5/6, you can also run it through your audio cables with a XLR - RCA lead, as long as you amp it it should work,
    Nick
     
  5. waynehoskins

    waynehoskins Active Member

    Messages:
    782
    Likes Received:
    49
    Location:
    Arlington, TX
    Sometimes works, sometimes doesn't work. Me, I wouldn't rely on it for an important input, though I'd have no problem using it for something non-critical like a confidence screen.

    At a couple hundred feet, I'd be looking at something along the lines of Belden 8281, maybe 8241 or 1505A, or somebody else's equivalent. You want a cable that's flat and low-loss from DC to 6 MHz, which regular RG59/U isn't quite -- it's reasonably low-loss down there but not flat. You may experience some chroma loss since the chroma subcarrier is up at 3.58 MHz (while the luma "carrier" is effectively at DC).
     
  6. NickJones

    NickJones Active Member

    Messages:
    950
    Likes Received:
    59
    Location:
    Somewhere far far away, Vic, Aus
    Yeah, alternatley, see if your venue owns the wireless units, they don't work for me (dispite the fact we own 6 of them....) as I just get a fuzzy picture for a number of reasons, but outside, could work....
    Just an idea,
    Nick
     
  7. ruinexplorer

    ruinexplorer Minion CB Mods Premium Member Fight Leukemia

    Messages:
    4,411
    Likes Received:
    826
    Occupation:
    Projectionist
    Location:
    Las Vegas
    I fully support Derek. Audio and Video cables have different impedance levels. While you can send video down an audio line using suitable adapters, that does not make it a good practice. Analog signals will already have some degredation over long lengths of cable (the amount varies on the quality of the cable and the strength of the signal). If you send a signal down a long cable that is not intended to pass the video signal, you will experience degredation at much shorter lengths.

    The same thing happens to lighting guys who use audio cables to connect their dmx devices. Over short lengths, no errors will probably occur. However, when longer lengths are involved, random things start to happen like stutters on moving lights or nodes that don't behave properly. This is due to data corruption. It was enough to drive me nuts to have to specify XLR data cable for my movers and inform the rental house that audio cable was not sufficient.
     
  8. NickJones

    NickJones Active Member

    Messages:
    950
    Likes Received:
    59
    Location:
    Somewhere far far away, Vic, Aus
    Yeah, this has been a problem for me, especially when you get cheap LED PARs that only take 3pin, I find it easier just to run a few meters of audio XLR then convert it strait back to 5 pin. Where it belongs :)

    And now back on topic:
    Considered the Cat5 route. It can be a lot cheaper alternative, especially if you make your own adapter. Can give you more info if you chose the route. You will still loose (some) signal due to the difference in cables, but I have worked on shows with huge budgets that chose this route, unless its HD you won't notice much difference. You can get signal reflection, due to a difference in impedance. But this shouldn't effect you too much.

    Nick
     
    Last edited: Apr 25, 2009
  9. SjonRokz4u

    SjonRokz4u Member

    Messages:
    26
    Likes Received:
    0
    Great Advice Guys!! Thank you. It turns out to be more like 300ish feet now. I think the bnc with adaptor seems to be my best route. Ive found some here that I can get. Although the cat5 thing sounds interesting. What are it fragility problems? Just breakage inside or ends? Also, with the cat5 can I break it down to 50' runs and use couplers to get my desired distance?
     
  10. gafftapegreenia

    gafftapegreenia CBMod CB Mods

    Messages:
    4,415
    Likes Received:
    576
    Occupation:
    Screw gun for hire
    Location:
    Chicago
    Keep in mind that the cable itself is not "BNC cable", merely those are the connectors that have been put on the ends of a length of coaxial cable. Coaxial cable is the same type of cable used to connect cable tv service. Coaxial cable can also be terminated in F and RCA type connectors. And of course, there are numerous types of adapters and couplers for each type of connector. Roughly speaking, BNC is more of the industrial standard, being more robust, while the F connector is more the consumer grade standard.

    As the guys have been saying, there are different types of coax cable. I'm still learning about that so I won't go any further.

    Also for further clarification. "XLR" is a type of connector, not a type of cable. Audio mic cable, color scroller cable, dmx cable - they all use an XLR type connector, just with different counts of pins. Due to common uses, the phrases "XLR cable" and "DMX cable" have come to mean a cable with a 3 pin connector for the former and a cable with a 5 pin connector for the latter. Not saying we all have to change how we speak, just making sure everyone is aware.

    The problem with standard Cat5 is two fold. First, the standard crimp connectors are fragile, and thus are prone to breakage. Nuetrik solved this problem with their EtherCon connector, an XLR style housing for the Cat5 connector. The other problem is the cable itself. The thin jacket doesn't protect the cable as well in stage use. For touring shows and other heavy duty use where the cable will be subject to wear, LEX products, and likely others, make a heavy duty Cat5 cable. (Complete with EtherCon connectors). I don't think you would need such a cable for this application.


    I think Derek has it right. Your rental house will have the coax cable and adapters you need. Radio Shack also carries the adapters, but they mark up their prices at least 5x. The internet is a great source for finding adapters and connectors and reasonable prices.


    Now CB, for a run of 300', might signal loss be a problem? Isn't there a signal booster he could use if that occurs? I ask this question for his sake and for my own.
     
  11. ruinexplorer

    ruinexplorer Minion CB Mods Premium Member Fight Leukemia

    Messages:
    4,411
    Likes Received:
    826
    Occupation:
    Projectionist
    Location:
    Las Vegas
    300' is still within the realms of good quality transmission for RG59 cable. I recommend using long runs with as few connectors as possible. Make sure that you use all of the same cable (don't mix RG59 with RG6 and keep away from RG58).

    Cat5 should be cheap enough to go with a single run. I recommend using an active balun for the best signal transmission. Again, you will get the best signal with the fewest connections between your source and projector. Every connection will cause a certain amount of signal loss.
     
  12. NickJones

    NickJones Active Member

    Messages:
    950
    Likes Received:
    59
    Location:
    Somewhere far far away, Vic, Aus
    Yes you can signal boosters,
    I simply amplify the signal with a TV. We have an old TV, sits halfway between the stage and the vison mixer, it means the actors can see what's going on onstage, but more importantly, it amplifies the signal. I picked up a cheap TV, with in & out, and on occasions it has sat coverd up & turned on, simply to amplify the signal. Still, this is only when I do really long runs.

    As for Gaffatapegreenia's comments, Cat5 is meant to sit in an office with bearded computer technicians, not supposed to come an play with us. However, Neutrik EtherCon RJ45's are Cat5's in XLR housing,
    [​IMG]
    [​IMG]
    These can be very useful. You can buy the carrier shells for $2.09 from Markertek. But this doesn't mean you can treat them like real lead.

    Nick
     
  13. gafftapegreenia

    gafftapegreenia CBMod CB Mods

    Messages:
    4,415
    Likes Received:
    576
    Occupation:
    Screw gun for hire
    Location:
    Chicago
    But the good people at LEX products knew Cat5 wanted to come and play with us, so they gave us this.
     
  14. NickJones

    NickJones Active Member

    Messages:
    950
    Likes Received:
    59
    Location:
    Somewhere far far away, Vic, Aus
    Very nice, but it kindof defeats the object of using normal, cheap, easy to get cabling, still, I am just talking about doing this for one time use, I'm sure this would be better long term.
     
  15. gafftapegreenia

    gafftapegreenia CBMod CB Mods

    Messages:
    4,415
    Likes Received:
    576
    Occupation:
    Screw gun for hire
    Location:
    Chicago
    Well right for this job you could get away using cheap standard Cat5. My ETC nodes are connected with standard Cat5 cable, but they rarely move and the cable is out of harms way. But the big touring shows, the LEX Cat5 is for them.
     
  16. ruinexplorer

    ruinexplorer Minion CB Mods Premium Member Fight Leukemia

    Messages:
    4,411
    Likes Received:
    826
    Occupation:
    Projectionist
    Location:
    Las Vegas
    The Ethercon connectors are especially nice in knowing that you have a good connection that will stay put and protected. The Lex cable is especially good for (as [user]gafftapegreenia[/user] suggested) repeated use for touring or staging companies. For temporary and occasional use, try to get stranded cable. If you are installing the cable, solid cable is better. The reason for this is that stranded cable will handle frequent bending without breaking, and has better tolerance for tighter bends.

    For this application, I don't think that you need to convert your signal to run over Cat5. I think that you would be adding a level of difficulty that is completely unnecessary.
     
  17. waynehoskins

    waynehoskins Active Member

    Messages:
    782
    Likes Received:
    49
    Location:
    Arlington, TX

    I agree. Added cost, added complexity, negligible benefit.

    I've got a 1000-foot length of RG-59/U cable at the shop that came out of TV, from one of the field shops probably. If composite video magically stopped at 50 feet, I don't think these guys would have built that. They also fire cameras down upwards of a mile of triax and somehow it works (and it's higher bandwidth than composite too).

    Run the coax. It'll work.
     
  18. NickJones

    NickJones Active Member

    Messages:
    950
    Likes Received:
    59
    Location:
    Somewhere far far away, Vic, Aus
    Yeah how do they do that? Fiber?
     
  19. ruinexplorer

    ruinexplorer Minion CB Mods Premium Member Fight Leukemia

    Messages:
    4,411
    Likes Received:
    826
    Occupation:
    Projectionist
    Location:
    Las Vegas
    While I'm not sure that you can go a mile with triax, you can easily get 1/4 of a mile. If you want to get some good info on this type of cable you can go here. Basically, a triax is similar to coaxial cable, but with the addition of an extra layer of insulation and a second conducting sheath. It allows a camera and the camera control unit (CCU) to communicate with more than just the transmission of the video and audio signal. For distances of about a mile, they most likely will be using fiber. Some of the new broadcast cameras have a fiber based "triax" cable. It's pretty cool, actually.
     

    Attached Files:

  20. Chris15

    Chris15 CBMod CB Mods Premium Member

    Messages:
    4,142
    Likes Received:
    422
    Location:
    Sydney, Australia
    Consider another is user of coax these days (though rapidly moving to Cat 5 and ethernet) - CCTV. A run of 60 odd metres that you are talking about is not a whole lot for a CCTV run and they are using the same cables we are talking about here.

    Now onto the side threads...
    2km is easily doable on 14mm Triax. The triax multiplexing is well designed. As distance goes up and you start pushing your bandwidth (which by the way is up around 600 MHz for HD, NOTHING like the couple of MHz of composite), you in order lose teleprompter, intercom, data, return viewfinder. The core video is at the lowest frequencies. The other thing about triax is that you are sending a not insubstantial amount of power back to the camera to run it. The CCU normally will up the voltage as much as needed to keep the camera, up to about 190 volts. It will also switch between AC and DC as needed. The double shielding helps keep up the bandwidth and RF rejection.

    The fibre "triax" cable ruinexplorer is talking about would be the SMPTE spec hybrid fibre cable. 2 strands of single mode 9mic fibre and 4 copper wires for power mostly. Good for 3km at least. MUCH MUCH harder to field repair than triax.:mrgreen:

    Composite video behaves like a good analog signal should. It doesn't magically stop like digital, it just degrades.

    I don't see what the issues is with mixing RG6 and RG59 unless there are propagation constant issues. They are both 75 ohm coaxes and you'll probably get more loss at the connectors than through cable mismatch. RG58 and RG8 are 50 ohm coaxes, I don't feel like going into the differences again - search it. the impedance mismatch from 50 to 75 and back again will only be a dB at each point but it also has the ability to produce reflections which can do nasty things to the image. RG6 will have less loss than RG59 (There also tend to be different grades of 59 - from those with an actual braided shield to those that have a marginal bit of copper for shielding.) If you need a really long run of coax you could step up to RG11, but I don't think it is needed for this.

    There are also the newer grades of coax - Belden and co make em. I know some of what I've wired in recent months has 4.5 GHz bandwidth. These are also an option and generally a smaller coax than 59, but you'd have to check the specs for loss per length comparisons.

    I would always favour the use of a single run of any cable from A - B especially if it is running anywhere close to the punters - less think for people to fiddle with and barrels will up the cable diameter and play silly buggers with any mats that might be covering it.

    I'm curious what Nick is talking about with making one's own Cat 5 adapter - are you talking about a proper balun or just connecting 2 wires together?

    DMX cabling = AES cable = the actually look at what impedance it's coming out as and keep it reasonably close to 110 ohm rather than anywhere between say 90 and 200 for an analog cable. Very acceptable to run analog on a digital grade cable, reverse may or may not work depending on how it's feeling.

    Cat 5 - rugged stuff is all well and nice - use with Ethercon (one will note however that Ethercon are only rated to 1000 mating cycles). The beauty of Cat 5 is that you can leave it behind rather than spend the time pulling it out... Solid is best for this - better bandwidth and easier to crimp than stranded. Now if Aviom would redesign their pods to take Ethercon... Another story for another thread.

    It's not designed for bearded computer boffins - it's designed to go in walls and stay there... Stranded is designed for patch leads.
    Basically for one off events, install solid core, terminate it at required length. If it ever gets back to the shop great, if not no great loss.

    Wireless - Nick only touched onto it - are we talking consumer 2G4 units? Avoid like the plague. 2G4 is a fickle beast and attenuated nicely by bodies which won't be there in testing but will show up for the gig. Also affected by WiFi and Bluetooth potentially.

    Oops, looks like this turned into a Shipesque post...
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice