Panasonic MX-50 Video Mixer Tips and Tricks

Where’s My “Zoom” and “Scroll”
In both the Panasonic product brochure and the service manual for the Panasonic WJ-MX50 video mixer, you’ll see the words “zoom” used to describe the compression capability and “scroll” to describe the Slide mode. No, “zoom” and “scroll” aren’t hidden features. Sorry.


Up On A Pedestal
NTSC broadcast standards dictates that a video signal, when displayed on a waveform monitor, fall within the range or 7.5 IRE for the color Black and 100 IRE for the color White. The Panasonic MX50 video mixer passes these standards perfectly when the video signal originates from an external source, however, the built-in color matte generator (background colors & color bars) are factory set at 0 IRE and 78 IRE for White. Panasonic states that this should not be a problem, even thought the Black level of 0 IRE is dangerously close to where the video sync signal resides (below 0 IRE).

NOTE: If you perform all of your editing in the “insert” model (video and/or audio) onto a “pre-blacked” tape with continuous control track, and you’re experiencing some top to bottom rainbow ripples on your inserted video, it may be from the Black being set at 0 IRE. I was getting that myself and so were a few others that I’ve talked to, however, since we started “pre-Bluing” our tapes with the MX-50’s solid Blue background color (no gradation), the problem has ceased.


Verifying Wipe Balance On the Panasonic WJ-MX50 Video Mixer
To verify if the wipe balance between the A and B busses are correctly set (symptoms would be obvious Auto-Take inconsistencies and the failure of a wipe completing itself when performed manually), hold the Event Number Buttons 1/5, 3/7 and the Memory button simultaneously while turning on the MX-50’s power. Press the WIPE button and the Auto-Take LED will start blinking. Bring the T-Bar (manual wipe lever) down to 8mm from the bottom of the B Buss position and you should see “255” Frames displayed in the Auto-Take Time window. Now move the T-Bar up to the A Buss position leaving 6mm of clearance from the top of the lever travel and you should see “000” Frames displayed in the Auto-Take Time window. Turn the MX-50 off, then back on again, and adjust both the Auto-Take transition knob and the Auto-Fade transition knob so that both indicate “200” Frames in their respective display window. These values should remain constant when moving the T-Bar manually from top to bottom. If your Panasonic MX50 video mixer failed either of these tests, a small adjustment of the MX-50’s internal switch board may be necessary. Check with your local Panasonic authorized service center.


Glitches In the Still
If you’re getting glitches or slight flagging at the edit points where you’re resuming a take of a Still or Freeze-Frame picture, it’s because the actual edit is taking place in the middle of a frame or field, instead of during the vertical blanking period. On the “pro-sumer” edit VCR’s, there’s not a whole lot that you can do about it other than repeating the edit a few times until the glitch goes away (when repeating the edit point, always start a frame or two prior to the previous edit point). If you’re using the high-end industrial decks with a dedicated controller try increasing the pre-roll time to seven or more seconds and make sure your Frame Servo switch is turned on. The longer pre-roll time will give the edit deck more time to lock up to the Horizontal Phase of the source deck, thus insuring the edit occurs between fields or frame, not on them. Even when the source deck is not being used (such as capturing freeze-frames of photos from your copy stand camera), the edit VCR still needs time to lock up it’s phasing. The nice thing about the Panasonic MX50 video mixer is that it puts out a strong and stable Still Mode picture for an editing VCR to synchronize to.


Creating The Film Look
You can give your videos a “film look” by using the first strobe setting on the MX-50 mixers. Add a slight orange/yellow tint, which will give the footage the look of an old 8mm movie. It’s a great effect for special openings and closing highlights.


Creating a Double Picture-In-Picture
With the Panasonic MX50 video mixer, you can create two Picture-In-Pictures (PIPs) on the screen at the same time. Simply recording one compressed PIP onto a submaster tape, then play that tape through the Panasonic MX50 video mixer a second time while creating another PIP.

To create two PIPs over a video background, record the double PIP over a blue background, then feed that tape through the mixer’s Chroma keyer. This time through, a third video picture will fill in the chroma key area. The end result is two PIPs over a video background.


Compression in the Still Mode
You can have a compressed still picture in a square wipe pattern by turning on the compression mode with the square wipe and use the T-Bar to size the P-I-P. Press the “still” button for whatever buss is compressed. The P-I-P will freeze, however, once it is pre-sized and frozen, you cannot change its size, but you can change its location with the positioner joystick. As a matter of fact, your can freeze both busses in square wipe compression mode. Just make sure that you use the T-Bar for transitions and not the Auto-Take button (which will dump the freeze). Also, realize that your freeze will be dumped anyway entering or exiting the compression mode.


Buss Switching in the Program Out Section
For straight cuts between the “A” and “B” busses, you can go directly from, let’s say, Source 1 on the “A” buss to Source 3 on the “B” buss by switching at the Program Out section in the upper right-hand corner of the Panasonic MX50 video mixer and you won’t get the slight digital freezing between cuts, either. This might be the easiest for some of you for live-switch, multiple camera venues. And, available on your “Preview” monitor is the video signal that emits from the “Effect” buss. Essentially, you could pull off a four-camera live-switch shoot with a total of just two monitors: a Preview and a Program. While sending your signal from the “A” buss, just bring down the T-Bar to the “B” buss and set up your next camera shot while viewing it on the Preview monitor.


Time Base Correctors and Video Mixers
If you are using a stand-alone time-base corrector with the Panasonic MX50 video mixer, the TBC should always follow the video output of a playback VCR, not after your digital mixer. If possible, connect the appropriate sync cables from the mixer to the “sync in” on the TBC and to the “external sync in” jacks on the playback VCR if it has one. This insures that all three pieces of equipment are “marching to the beat of the same drum.”


Creating Metallic Titles
Here’s a little recipe that’ll spice up an opening or closing title sequence. It is recommended using this effect only over a solid background.

Create your title using white lettering against a black background. This can be done best with an external dedicated keyer such as the Videonics Titlemaker (large display fonts are best), or with a camera pointing at a title card. Assign this titling source to both the A and B busses.

Turn on the digital effects section of your mixer and press the still and frame buttons for both busses. Press the negative button of the B buss only.

Engage the square wipe pattern with no compression, aspect ratio on, the one-way and the reverse buttons off. Press the soft button twice to give the softest wipe edge.

Turn the aspect ratio knob all the way to the right so that the wipe pattern will run the horizontal length of the screen. Starting with the T-Bar on the A buss, bring it down slightly to the B buss. This will create a thin and wide rectangular wipe. By using the positioner and/or multi-button, position this wipe so that it will run across your title, preferably down the middle of the title and just a portion of the height of the title.

This can be tweaked to personal taste. At this point you should be seeing the negatively effected portion of your B buss title (a grayish swath) overlaying a portion of your un-effected A buss title. We’re almost there.

Turn the DSK (Downstream Key) section on and press the A button and the fill matte button. Choose your matte color selection. For purposes of this tutorial choose black. Bring up the low-level slider (the right slider) until the matte color (in this example, black) completely fills the background up to the perimeter of your title.


Metallic Tweaking
To enhance the metallic effect turn on the video button in the fade control section of your mixer and choose the B buss (press the B button). Bring the slider down approximately 1/3 to 1/2. This will slightly darken the white portion of your title and should greatly enhance the metallic illusion. Again, season to taste.

How about creating different lighting angles on your lettering? This can be accomplished to great effect by pressing the multi button in the wipe effects section, five times. Bring the T-Bar down to the B buss and use it and your positioner to achieve various results.

Other matte colors can be used in your DSK section, some more effectively than others. Try blue and gradient blue. They seem to complement the metallic illusion nicely. By choosing black as your fill matte you can key your metallic titles over live video on a second pass using the luminance keyer. Simply, record your metallic creation to a sub-master, play it back on the B buss, turn on the luminance key button (make sure the T-Bar is resting fully on the B buss) and tweak with the slice control. I don’t recommend doing this because of obvious signal degradation in the second pass, but, you may find it useful in a pinch. One more hint. Use the joystick positioner to place the wipe pattern off-center for different looks and lighting angles. Just experiment.


The Panasonic MX-50 Video Mixer Missing Frame
A few Panasonic WJ-MX50 users have noticed an occasional “missing frame” of video on tapes that have been recorded through the Panasonic MX50 video mixer.

Not a disturbing alert, however, every now and then a frame of video will be dropped when the source signal is a playback VCR, typically a consumer-level VCR.

Why? Because the MX-50, like it’s other digital mixer cousins, grabs a frame at a time, processed it, and then spits our that processed frame at a speed determined by the MX50’s “timing clock” (the internal sync).

The trouble is that the Panasonic MX50 video mixer does such a good job of spitting out video at a constant rate, it can’t account for timing errors, and tape speed fluctuation from the playback VCR, especially if the VCR is “spitting out” it’s signal at a non-constant rate.

This phenomenon has been know to happen with time base correctors whose process speed is a constant 30 frames per second and the playback VCR’s process speed is varying from 29 to 31 frames per seconds.

Consequently, the time base corrector, or a digital frame synchronizer, cannot process what is supposed to be there during a certain time period and subsequently the frame may be lost. Or even, in some cases, the frame may be doubled.

So, how do you fix that?

Well, obviously you’re going to have to get the playback VCR and the digital mixer to march to the beat of the same drum. And fortunately, this can be done with a VCR that can receive a sync timing pulse from the digital mixer (or TBC).

And that’s why the Panasonic MX50 video mixer has both Reference Sync and Advanced Sync outputs to send it’s timing pulse to either a playback VCR with “external sync in” and/or to a TBC that has “external sync in” (the TBC passes it’s timing pulse on to the playback VCR).

Typically, you’re only going to find these “external sync inputs” on the higher-end industrial VCRs (i.e., AG-7650, BR-S611, BR-622, EVO-9850, etc.)

The good news is, you are really going to have to look hard to find this occasional “missing frame”

II mean, slowing down your edited tape and walking through it frame by frame with the jog dial. So, don’t worry about it that much. It doesn’t happen that often and if you have to search for it, your clients will never see it.


Create a “Trail” Effect With The Panasonic MX-50 Video Mixer
You can create a really cool effect with the Panasonic WJ-MX50’s “trail” function. This function allows you to fly-on a picture that leaves repeating “video footprints” of itself behind as it comes on the screen. Most of the time you will use this over a solid black background, however you perform this effect over another video image.

Here is how you do it. Assign your trail footage to the “B” buss on the Panasonic MX50 video mixer and assigning your full-screen footage to the “A” buss, turn on the Luminance Key mode and adjust the Slice control accordingly.

Press the Trail button. Your full-screen picture will fill in the solid black area underneath the incoming trail. This Luminance Key trick will also work with other effects within the Panasonic MX50 video mixer that introduce compressed pictures over a black background, such as the Multi mode.

A simultaneous “double trail” effect can be created by setting up a horizontal compressed split-screen with the dividing split in the center of the screen. Then press the Trail button for the “A” buss and then immediately press the Trail button for the “B” buss.

Remember, the actual trail will enter the screen from either the right or left side, depending on where you have your joystick placed (right or left).


The Panasonic MX-50 7.5 Video Mixer IRE Black
The Panasonic MX50 video mixer does not put out an NTSC standard “color black” in both the matte color section and the video fade section.

Normally, this does not pose any serious problems, however, every now and then some time base correctors will get a little flustered when trying to discern the color black at 0 IRE from the video sync information that resides in the 0 to -40 IRE neighborhood. (That’s why the color black is normally 7.5 IRE.)

You can, however, obtain 7.5 IRE black from your Panasonic MX50 video mixer simply by substituting the background color white with the color level knob set at that “9 o’clock” position.

So, if you need to fade to “Black”, just fade to “Matte” and select “9 o’clock white” in the matte generator. If you need black drop shadows on your titles when going through the Downstream Key Section, select “9 o’clock white” in the matte generator.

Like I said, under normal circumstances, the MX-50's 0 IRE black won’t upset your productions, but if you want to be on the safe side, try “9 o’clock white”. And if you were wondering where the “chroma” level knob in the color corrector section should be if your want “unity gain” (that’s where the knob should be if the color corrector is turned on and you don’t want to add or delete any chroma gain), try the “2 o’clock” position on that knob.

(The preceding levels were determined by feeding the Panasonic MX-50’s output into a waveform monitor and a vectorscope and then comparing the test signal’s level with and without the processing of the Panasonic MX50 video mixer.)


Another Way to Generate 7.5 Black
This is another, more accurate way, of obtaining a 7.5 IRE Black level out of Panasonic MX50 video mixer: use the background color Blue with the color level control turned all the way counter-clockwise, with the Gradation turned off, of course. (Sure enough this technique puts the black level right on the 7.5 IRE line.)


Up On A Pedestal
NTSC broadcast standards dictates that a video signal, when displayed on a waveform monitor (or the Studio 1 Video Level Meter), fall within the range or 7.5 IRE for the color Black and 100 IRE for the color White. The Panasonic MX50 video mixer passes these standards perfectly when the video signal originates from an external source, however, the built-in color matte generator (background colors & color bars) are factory set at 0 IRE and 78 IRE for White. Panasonic states that this should not be a problem, even thought the Black level of 0 IRE is dangerously close to where the video sync signal resides (below 0 IRE).

NNOTE: If you perform all of your editing in the “insert” model (video and/or audio) onto a “pre-blacked” tape with continuous control track, and you’re experiencing some top to bottom rainbow ripples on your inserted video, it may be from the Black being set at 0 IRE. I was getting that myself and so were a few others that I’ve talked to, however, since we started “pre-Bluing” our tapes with the Panasonic MX-50’s solid Blue background color (no gradation), the problem has ceased.


Freeze Frame Recovery
Have you ever dumped a video still from memory while stringing together a photo montage?

Here is a simple solution to that problem. You can recover the lost frame by removing the edit master from your editing VCR and place it in the playback VCR. Bring the tape up to the point where the still picture was last recorded and re-freeze it again into your digital mixer.

Take your edit master tape out of the playback VCR and put it back into the editing VCR. You can now resume your photo montage.

You shouldn’t have any shifting of the still picture or loss in resolution if your playback and editing VCR are the same make and model.