[quote="scottgfx"]Could DC offset be an issue?[/quote] No, not really. Any DC offset would be noticed as hum. I'd think you'd notice that straight away.

Could DC offset be an issue?

[quote="Perry my Cat"]Hi Dave If a producer ever tells you to put iso in a tele ask them when is the talent going to draw on something no one else will see. Also I'm curious were you usung a lum key? I was wondering why you would use a lum? M ichelle[/quote] Doing a lum key was not my best idea. I did a linear key tonight and it worked better. - Dave

If I am using something like a CODI where I get only 1 signal into the switcher, I map the fill signal as its own key. Not a true linear key but it effectively works like one. I find it makes for really clean edges. Rather than using crosspoint holds, in case of problems I map Black into the key side of the signal (3 and 4K) . If I am on a Kalypso I build Macros in the Source Patching Menu that patch the Tele "HOT" and "NOT". The best thing about the Macros is that i can instantly override talent if they are having problems clearing the tele. I can also easily clear the tele while running the open to prevent doodling by the color analyst who wants to "practice". As for tele being fed by the ISO router, I warn the production team before hand. If it fails on the air because the producer is hammering on the ISO router, they learn a valuable lesson. Happy punching! scott

Hi Dave If a producer ever tells you to put iso in a tele ask them when is the talent going to draw on something no one else will see. Also I'm curious were you usung a lum key? I was wondering why you would use a lum? M ichelle

Well there's your problem!! Unless the director was saying 'eh' after every command, the truck didn't know what to do!! [quote="Dave Armini"]This was a Dome truck by the way. Don't know which one. - DA[/quote]

This was a Dome truck by the way. Don't know which one. - DA

[quote="Mike Cumbo"]Dave, the only issue with telling the guys to put program in the tele is that some producers still will not listen to common sense and they insist on ISO being put in that thing. BTW, I have seen this also on a truck with a Sony 8000, 1080i, and a Pesa router. It is not a GVG only issue.[/quote] I know Mike. But if no one is around I'm going to suggest Program I guess. Also I think I'll avoid doing a luminance key if possible. I think Ed's point about luminace key black levels may be right on. - DA

Dave, the only issue with telling the guys to put program in the tele is that some producers still will not listen to common sense and they insist on ISO being put in that thing. BTW, I have seen this also on a truck with a Sony 8000, 1080i, and a Pesa router. It is not a GVG only issue.

I think you guys are on the right track. My first question is what kind of tele? Since this was a visit feed in the Rose Garden I'll assume it was a Mira truck. Last time I checked they had analog teles. If the tele input was being fed from the iso router, then every time there was a cut the input to the tele is going to have to relock, not only from the router cutting but also from the downconverter feeding the input to the tele having to reclock. Then, because it's an analog tele and you're in a digital truck (unless you had M-1, in which case you could chalk all this up to the layers of dust and 10+ year old cabling!) the key signal is going to have to be upconverted. You've now got three possible sources for the glitches (router, downconverter and upconverter). For this very reason I almost always feed program to the tele. -J

Dave: There are some other things that may cause hits. If you are doing a LUM key and the black levels change abruptly in the Tele this may cause it to take a hit. The switcher is, of course keying out the black of the Tele and sometimes, when the hit occurs, the black levels will spike past the threshold setting of the clip. So what actually happens is the switcher doesn?t key out the spiked blacks and a flash from the spiked black level can be seen (in this case it will be matte filled garbage). When doing a LUM key (which I thankfully don?t need to do any more) I try to set the clip (with a complicated drawing on the Tele ? more than just a line or two) and I run the clip completely through its range. I try to set the threshold (when it actually keys) so that if the black level does change then hopefully the switcher will still key it out. If you run the clip so the edges of the Tele get ragged then back off just enough this is usually pretty close to a good threshold. I?d be sure there are no special characters (which there shouldn?t be for an old-fashioned LUM key Tele) that may not key correctly, such as dotted lines etc. The real answer is what Mike was alluding to ? try to eliminate any potential hits due to bad cabling or ISO routers. Usually I?ve found the HD ISO routers to be the main culprit due to the timing issues Mike talked about. Sometimes putting a Frame Sync on the ISO output can help. If your Producer will let you switch the feed you can always use an Aux Bus from the switcher, that way there will be no timing issues. If all else fails you could give the Producer a remote Aux panel for the Kalypso ? if the truck has one. Hope this helps. Ed

Thanks for the reply Mike. The Iso Router feeding the tele may have been it. At least now that I know there is a chance for some hits to occur if Iso is feeding the tele, then when the camera guys come up front early in the day and ask me what should feed the tele.....Program or Iso.....I'm always going to say Program now. - DA

Dave, several thoughts. First, was a router feeding the tele or program? I have seen burps when an ISO router is used to feed the tele. Few trucks have all their sources timed in the router and the changing phase causes the burp. If the burp occurred as the producer was changing sources on the ISO router we may have your cause. BTW, I usually use my tele as a linear key, so I think we can cross out the lum key as the cause. The second possibility is connectors on the touch screen or the actual video cables that the utes and camera ops ran. There are few legs at the table before a game, maybe a bad cable that turned up when someone stepped on it?