Problems with DTS 70mm Playback

[Michael Zarits]

Did I dream that even/odd pattern with older players or was that actually a thing?

I'd be interested in that as well.

[Marco Giustini]

The "excessive timecode" relates more to Brad's input an memory that there were a handful of modern 70mm prints where Fotokem was doing unusual or inconsistent things with timecode on the tails. Perhaps there is some out of bounds behavior when a print is unusual like this that is specific to the XD20s, it would require Jerry reporting on the presence of non-presence of timecode all the way out through the tails on his testing print.

I didn't meant to sound harsh, Ryan. Learning on whether timecode was printed on the tails might be a data point - what I meant to say was that the system is supposed to work with or without timecode on the tails. As Mike confirmed, the DTS system will start accepting timecode from the following reel regardless. Even if no head or tail leaders were spliced, the system would have the time in between the TC reader and the gate to process the new TC and start playing the new reel. Considering that DTS has 4.5 seconds of "flywheeling" when TC is lost, that is really a non-issue.

We're all looking forward to Jerry's feedback now

[Ryan Gallagher]

I didn't meant to sound harsh, Ryan. Learning on whether timecode was printed on the tails might be a data point - what I meant to say was that the system is supposed to work with or without timecode on the tails. As Mike confirmed, the DTS system will start accepting timecode from the following reel regardless. Even if no head or tail leaders were spliced, the system would have the time in between the TC reader and the gate to process the new TC and start playing the new reel. Considering that DTS has 4.5 seconds of "flywheeling" when TC is lost, that is really a non-issue.

We're all looking forward to Jerry's feedback now

Did not read it as harsh, no worries. In my head I just keep circling back to the fact Jerry is only experiencing this on “some” but not all 70mm prints, and that variation in printing practice combined with maybe an unusual XD20 only behavior (perhaps due to a non patched version), could be the compounding factors.

[Marco Giustini]

Speaking of 70mm, I’ve stumbled into a 70mm DTS head which would show a green LED even when no film is loaded.

is that a known behaviour? I remember that LED is driven by the player and basically matching the ‘time code’ light on the front panel.

A ‘always green’ head would mean the inability to diagnose time code issues.

is this an isolated case or maybe due to some specific HW version?

[Steve Guttag]

Check the wiring of the cable. If pin 9 of the reader has any short to ground/reference, the LED will light. So, anything to cause that line to go low, even a leaky optoisolator (if they're using them) would do it.

[Marco Giustini]

Thanks - so you confirm that the behaviour I have in mind (following the Timecode status) is the expected one?