making a stage opaque

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Andy Dolph

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Feb 25, 2024, 1:26:48 PM2/25/24
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In Qlab 5 is there a way to make a stage opaque when something is displayed on it but only when something is displayed on it?

Here's the scenario - working on a very complex show (roughly 1900 QLab cues) with a projector covering the whole stage - in the middle of the stage is a free standing projection screen - most of the show I'm projecting full stage images that are meant to cover everything including the projection screen, but there are also a ton of places where I have a separate image on the center screen.  If I have to, I'll make all of those images the exact size and shape of that screen in pixels so they fill the whole thing - but it would save me a ton of time if there was a way to tell Qlab to blackout any parts of the that screen the current image doesn't fill.

As an example - the screen is 4:3, so if I'm projecting a 16:9 image on it I'd love Qlab to fill in above and below it with black bars.

But then when I fade and stop the image the black bars would need to fade and stop with it.

The more I'm describing this - the more I think I DO need to do this in each image file, but I'd love to be wrong.

thanks!

Andy

micpool

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Feb 25, 2024, 1:43:26 PM2/25/24
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You need 2 stages.
A Full projector resolution 16:9 ratio e.g 1920x1080
A Centre Screen Stage 4:3 ratio, approximately sized to the number of pixels that fall on this screen, perhaps 800x600?

Stages can have their layers set independently of cues, so you would set your Full Projector Stage to Bottom and Your Small Projection Screen to top.

Stages.jpg
Screen recording attached

Mic
2 Stages.mov

Andy Dolph

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Feb 25, 2024, 1:55:14 PM2/25/24
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Thanks Mic,  I've got that part working in just the way you describe - here's what I'm trying to add - to use the example in your video - when Small comes in, I want it to black out the parts of the 800x600 stage it's not filling so I don't see the image from the big stage coming through anywhere in that 800*600 box.

that's what I'm wondering if there's an easy way to do in Qlab...

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Ethan Eldred

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Feb 25, 2024, 2:18:01 PM2/25/24
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Adding a “blank black background” cue, sent to that smaller stage in the bottom layer behind any cue that doesn’t fill the 4:3 screen would accomplish what you’re looking for! 

E

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Ethan Eldred
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UCSD Department of Theatre and Dance
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Andy Dolph

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Feb 25, 2024, 2:30:58 PM2/25/24
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Thank you - That's what I was afraid of lol - but it's doable.



Andy Dolph

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Feb 25, 2024, 2:32:38 PM2/25/24
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Just want to make sure I understand this correctly - Each stage has a set of layers which is essentially isolated inside that stage, and then there's a totally separate, unrelated set of layers that controls the layering of the stages themselves?

On Sun, Feb 25, 2024 at 1:43 PM micpool <m...@micpool.com> wrote:
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micpool

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Feb 25, 2024, 2:34:39 PM2/25/24
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Correct

So a cue set to top layer to a stage set  bottom layer is behind a cue set to bottom layer sent to a stage set top layer

micpool

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Feb 25, 2024, 2:47:56 PM2/25/24
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On Sunday, February 25, 2024 at 7:30:58 PM UTC Andy Dolph wrote:
Thank you - That's what I was afraid of lol - but it's doable.

Why don't you just fade out the background image when you bring up the small screen image? 

Andy Dolph

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Feb 25, 2024, 2:54:41 PM2/25/24
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because I want the small screen image inset in the background - I just don't want the background to bleed onto the small physical screen the small images are projected on.

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Sam Kusnetz

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Feb 25, 2024, 3:05:58 PM2/25/24
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On Feb 25, 2024 at 2:32:22 PM, Andy Dolph <acd...@gmail.com> wrote:
Just want to make sure I understand this correctly - Each stage has a set of layers which is essentially isolated inside that stage, and then there's a totally separate, unrelated set of layers that controls the layering of the stages themselves?

Yes!

More detail here:


-sk
Sam Kusnetz (he/him) | Figure 53


micpool

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Feb 25, 2024, 3:07:39 PM2/25/24
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On Sunday, February 25, 2024 at 7:54:41 PM UTC Andy Dolph wrote:
because I want the small screen image inset in the background - I just don't want the background to bleed onto the small physical screen the small images are projected on.


Sorry, I don't understand why the  2 stage solution I outlined in my previous post doesn't achieve precisely that. 

Mic

Sam Kusnetz

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Feb 25, 2024, 4:19:53 PM2/25/24
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Andy

I agree that Mic’s two-stage method is best here. If you want to avoid using two images per cue (i.e. your image plus a black backdrop image) you could preemptively edit all your images to have a very wide black border.

That way, your images could be zoomed down while still filling the smaller surface with their black border.

Andy Dolph

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Feb 25, 2024, 8:02:08 PM2/25/24
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I’m using Mic’s 2 stage method already - totally agree that’s the way to do it.

And I think you are right that I’m going to use a photoshop action to batch the files and add the boarder as you describe.

On Feb 25, 2024, at 4:19 PM, Sam Kusnetz <s...@figure53.com> wrote:


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micpool

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Feb 26, 2024, 7:26:23 AM2/26/24
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You could use 3 stages layered

1. Full Background
2  Small Screen Background for black solid cue
3  Small screen content

That way, you have independent control of when the small screen is a screen, regardless of its content.

Bordering all the small screen content has one significant advantage, in that you can just set all images to the bottom layer and crossfade by starting them and fading and stopping the current image regardless of their mixed aspect ratios.

If you think about how QLab makes the desktop opaque when video content fades in, i.e the display snaps to black and then the video fades up, your original question " is there a way to make a stage opaque when something is displayed on it but only when something is displayed on it?" might not work that well in practice, even if it was an option.

Mic

Andy Dolph

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Feb 26, 2024, 10:32:16 AM2/26/24
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That makes sense - thanks very much!

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