Film-Tech Forum ARCHIVE: DA20 reverting to SR because of edge cue?

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Posted by Bernie Anderson Jr (Member # 410) on 04-15-2012, 11:33 PM:

Hi guys,

This is something I'm running into at home with my DA20/CP65/Cat 702 setup. I'm using edge cue foil for 2 proj. changeover automation and it seems that the cue is making the DA20 revert to analog for about 1 sec. Its a standard precut edge foil cue that came from Strong, so it measures about 3-4 inches long.

Some my thought would be, to just swap inboard and outboard cues (since the other cue is for curtain control, which is really only used at the end of the feature and can be cut shorter to cue the relay).

Any thoughts?

Thanks

Bernie

Posted by Ken Lackner (Member # 1002) on 04-16-2012, 12:42 PM:

Chances are, yes, it is the cue that is causing the reversion. If you place it on the film such that it covers the SRD track, 3-4 inches is plenty long to cause a drop out. If you are folding the cue over the edge of the print, that will likely cause just enough of a shift when that part of the film goes through the reader that the track will drop out.

What type of cue detector are you using? If a proximity type, the cue should not have to be longer than half an inch; even shorter should work just fine. There are the older type of readers that require the foil to make contact between two rollers, but I am not personally familair with those and don't know how long the cues need to be for those to work. But I would think 4 inches is way more than enough.

Posted by Bernie Anderson Jr (Member # 410) on 04-16-2012, 05:25 PM:

The cue readers are the old Kelmar contact cue readers with an inboard and outboard cue. The foil works as a switch to complete the circuit.

I swapped inboard for outboard and vise versa, so the shut down cue is on inboard cue. I ran a test film from machine 2 to machine 1 and it didn't revert, but when I ran from machine 1 to machine 2, it sounded as if it reverted. I will have to check again and watch the light instead of listening for it.

Bernie

Posted by Marco Giustini (Member # 4544) on 04-18-2012, 02:23 PM:

You have reversion after 4 unreadable blocks. Keep in mind that the foil will make other blocks unreadable because the print won't bend as usual on the drum where the foil is applied.

But if you apply the foil at the end of a reel, the caching system of the DA20 should kick in and prevent the reversion (you should see "0" as error rate for a moment). How far from the end of the reel do you place the foil? Do you put it on emulsion side or base side?

Posted by Bernie Anderson Jr (Member # 410) on 04-18-2012, 06:18 PM:

The cue is placed 14 feet from the changeover cue dots and it is folded over the edge of the film.

Posted by Monte L Fullmer (Member # 2797) on 04-19-2012, 11:16 AM:

Use thinner cue tape, or when you lay the tape on the film, just don't cover the SRD track but lay over the SDDS track only and trim off the excess - don't fold over.

Posted by Marco Giustini (Member # 4544) on 04-19-2012, 11:18 AM:

unfortunately the cache should cover only up to 4.1 feet of film before the LFOA (66 frames).
You may want to try smaller cues, not folded around the film. I used to place 8 perforations cues; eventually found that a very thin 4 perfs cue - not folded - was perfectly fine for my automation.

Posted by Tony Bandiera Jr (Member # 2365) on 04-19-2012, 12:47 PM:

Guys, you are not paying attention to one thing: Bernie's got the old cue detectors where the foil must bridge two rollers to make contact. Shorter cues are NOT possible with them, and if you don't wrap them around they may not have enough continuity (electrically) to work reliably.

Bernie, you need to get a set of FM-35's or other non-contact cue detector and you can then use either side of the film with a single frame cue that will hit every time. I am positive that with a little looking in the "Equipment For Sale" section you can find someone selling them..or put up a "wanted" post.

Problem solved.

Posted by Bernie Anderson Jr (Member # 410) on 04-19-2012, 01:32 PM:

Thanks guys,

What I've done to date is swap the inboard and outboard cue wires, so this way C/O and shutdown cues are on inboard side, plus the automation works on a 2 inch cue instead of the 4 inch cue. I've only ran one changeover and so far it seems to hold in Digital on the DA 20. The only thing I think I heard was a faint static pop at the point of changeover. I have to listen to it again to be sure.

Bernie

Posted by Marco Giustini (Member # 4544) on 04-19-2012, 02:34 PM:

thanks Tony for sharing that with us.

Posted by Monte L Fullmer (Member # 2797) on 04-19-2012, 04:13 PM:

Congrats on the find and hope the issue is resolved for you then.

Reason why I made the mention of the trim is that I worked in a 4plex booth with V5's and had the Xetron dry grounding roller contact type failsafes where a good length of cue tape had to make them work.

We were having sensing problems, thus I tried the one side and trim trick, and this procedure really did help-why I suggested it for the OP here.

thx-Monte

Posted by Tony Bandiera Jr (Member # 2365) on 04-19-2012, 11:27 PM:

Marco and Monte: I do apologize if the tone of my post did not read well...I typed it in a hurry and only now, looking back realized it sounded harsh.

Monte: I am really surprised that worked for you..my past experience with that style cue detector had only a long, wrapped cue working reliably for my setups. The exception was the copper foil cues (I think Kelmar made them) that were about 3" long and fit nicely between the perfs and outer edge of the film..they even came with a nifty block so they would be aligned perfectly. Alas, like all really good things, they got discontinued.