Production Switchers

Good morning- Our station has a Ross Vision and XPression. Our opens run via XPression as they key to reveal the camera at the end. I am noticing, however, when watching our program feed on a TV with 100% of the pixels displayed (zero overscan), that the bottom row or so of pixels doesn't key properly... as in, the open does not fully cover the bottom row or 2 of pixels, resulting in a visible camera cut underneath. Because of this any action occuring at the very bottom of the frame on the camera is technically visible (although this is largely unintelligible to the viewer and honestly not even going to be displayed on most TVs, it's something that we would like fixed if reasonably possible.) Has anybody else experienced this before and/or have a solution to this?

Thanks

Hi Mario, you should check the reference timings for both the XPression and the switcher. Your description sounds like a timing offset or simply that the graphic itself doesn't fill the screen.

If the key is full screen (with no timing offset) you will not see any part of the background.

Nigel

#Vision

This is an issue when your using say BB with and HD format. In the XPression hardware Config of the matrox board you have to adjust the Delay timing.

What is your Production Format and what is your Reference Format?

What Nigel is explaining is exactly correct -- but you fix it inside the XPression.

Les

#Vision

Hi Nigel and Les- we found the delay timing configuration within our XPression software... and we found that while adjusting the delay timing, we were able to shift the keyed graphics *upward* by adding timing delay, but could not bring the graphics *downward* by going into the negative values for vertical timing. Therefore, our problem is not able to be solved... Is there some operation we are missing?

Les- Our board is referencing at 1080i 59.94 and XPression is referencing at 1080i 29.97. There is no oprion available in the drop down box in XPression to change the reference to 1080*i* 59.94 (if that makes a difference), but it has an option for progressive 1080 59.94. Obviously the progressive format would not work for our congifuration.

Any further ideas or information I can provide to help?

Thanks

-Mario C.

#Vision

Mario -- your going to need to set it to 1024 Vertical lines or something like that. Correct the negative does nothing with the tri level sync.

Yes XPression reports that as 29.97 cause that is frames though interlaced format. The switcher will report as 59.94 because of fields which technically is the way it should be represented as per SMPTE.

Les

#Vision

Alright... We seem to be goign in the right direction? We're still tinkering... and we're going to be running tests right now (just waiting for Prod Cntrl to open up), but by adjusting the reference timing this far ahead, would it effect the actual timing between audio and video and response time of loading a graphic?

Thanks!

#Vision

Just made these modifications and ran some tests.... Problem= fixed! Set our vertical timing to 1130. We ran some opens with audio and it *appeared* to remain in sync- thanks all for your immense help!!

-Mario C.

#Vision

We're having the same issue, with a line or two at the bottom showing up underneath the key. Where did you find the setting to adjust the vertical timing to 1130?

#Vision

Joe -- It is in the Hardware configuration Menu. Then you click on the Matrox Card in your frame buffer settings. Then find the Reference Tab an you will have the H and V settings.

Les

#Vision

Thanks for getting back so quick, Les. Changing the vertical to 1130 like Mario did only moved the unkeyed gap up. However, changing the blackburst reference from auto-detect to 1080p 59.94 fixed the problem on the studio box, and the same setting with the vertical set at 2 fixed the blue box problem.

#Vision

Joe- interesting discovery. Additional note- for one reason or another, the value needed to achieve success with the method Les provided was a smaller number... vertical timing only needed to be changed to 600 something...

#Vision

XPression displays the frame rate in Frames Per Second (not fields per second), so 1080i29.97 is exactly the same as the switchers definition of 1080i59.94 (fields per second).

If you are feeding tri-level sync to the ref input of XPression, the vertical adjustment should be set to 1124.

If you are feeding 480i SD black to the reference input (and outputting 1080i) then the vertical adjustment should be set to "-2"

#Vision