Crazy Keystoning

Hey All,

I've got a theater show that I have to program in the next week (it starts thursday of next week) that requires some absolutely crazy keystone correction for a lot of cues.

The set consists of 6 giant boxes on wheels (16ft high, 8ft wide, 4ft deep) that move all around the stage during the course of the play. See the attached images, the lines represent the throw of the projectors.

I have one catalyst server running three projectors using a Matrox Triple Head 2 Go, so it is actually just one huge output. We have done a show using this setup and it works quite well, but I've never done keystone correction.

For a lot of the cues, the boxes are lined up pretty well with the projectors, but there are several where they are not, so I need to keystone all the layers separately to fit the images on to each box.

I was playing around with the keystone today but didn't get much time to figure things out. I was able to apply the keystone setup effect to the layer which got me a grid to work with. I was able to rotate and scale and move the corners of that grid to fit on to the surface that needed the image. However, when I switched back to the keystone effect, the image was huge, and stretched across all three projectors.

In playing a bit more, I found that when the keystone effect was applied, the image was coming out sidways, although I could rotate it, but adjusting the scale had no effect.

Some scenes use up all 14 layers (mostly images, not much video) and each layer needs to be individually fit on to the set pieces.

Is what I'm needing to do possible? If so, I need some pointers on how to make the keystone work for me. The directors going to be rather unhappy if I tell her it is impossible smile

I'm running Cat v4 m165, controlled via art-net by a magicq pc system.

Thanks for any help you can provide... this is going to make my crazy!
--
Landy Bible
LJB2of3 Lighting

Landy,

There are 2 ways to appraoch this, and they can be done separatley or both together.

The first thing you want to look at is using the "Mix Shape Control". This will allow you to Keystone each of your three Output Mixes separately directly via DMX. It only takes up 8 channels of DMX per Mix, and is patched in the Cat server the same way a layer is.

This looks like it will solve your problems in pictures 2 and 3.

In picture 1 if you need say 1 layer per set piece, then you will need to either keystone on the layers or do some serious prep of your content.

To Keystone on a layer you must select the proper Visual FX mode of "Movie on Keystone" to get the Keystone parameters to work on that layer.....and yes this Effect will change your scale.

Another thing that might help you is to use Scale to shrink your layer down some. Then use X and Y position to move it to where you need it. Followed by fine tuning with the layer Keystone.

So in short for you picture #1:
1 - Set your Mix Shape Control to line up the edges as best possible for all the set pieces covered by each mix
2 - Set Visual FX to "Movie on Keystone" for all the layers you need to use

Then layer by layer:
3 - Scale image down
4 - Move with X and Y Pos
5 - Adjust with Scale and X/Y Pos to get as close as possible
(You also may want to try adjusting either the Horizontal or Vertical Aspect ratio here as well)
6 - Use Layer Keystone to clean it all up

Hope this helps:)

dont use keystone on a layer- dont even touch it-

dont mess with the keystone visual fx layer parameters -

use keystone on sub-mix - then all perspectives and scales on layers stay aligned - and you can playback multiple layers on the same object - keeping everything aligned - just by routing a layer to an output mix - its much much easier.

use one sub-mix for each object on stage-

you will need an alignment image which allows for easy adjustment for every object on stage - probably matching the aspect ratio of the objects on stage.

Quote:

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Originally Posted by samsc

dont use keystone on a layer- dont even touch it-

dont mess with the keystone visual fx layer parameters -

use keystone on sub-mix - then all perspectives and scales on layers stay aligned - and you can playback multiple layers on the same object - keeping everything aligned - just by routing a layer to an output mix - its much much easier.

use one sub-mix for each object on stage-

you will need an alignment image which allows for easy adjustment for every object on stage - probably matching the aspect ratio of the objects on stage.

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Of course using Mixes is the ideal way to go....as long as you have a full PRO version server this should work well....otherwise you will run out of available Mixes fast.

So in this case, set up 6 Mixes, 2 per "output" of the Triple head that cover the entire raster of their respective "output", and then you can use the Mix Shape Control to adjust them to fit the set pieces.

If, for some reason, you need more than 8 Mixes at once to do this, you will get in to trouble, and have to use some of the steps I listed initially.

Quote:

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Originally Posted by Marty Postma

Of course using Mixes is the ideal way to go....as long as you have a full PRO version server this should work well....otherwise you will run out of available Mixes fast.

So in this case, set up 6 Mixes, 2 per "output" of the Triple head that cover the entire raster of their respective "output", and then you can use the Mix Shape Control to adjust them to fit the set pieces.

If, for some reason, you need more than 8 Mixes at once to do this, you will get in to trouble, and have to use some of the steps I listed initially.

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i have watched people setup these things and done them myself. its much easier setting up the mix.
i did a show at the royal opera house earlier in the year - chris wheeldon with this type of set arrangement -
lloyd newson of dv8 is also doing something similar on his current touring show. lots of little bits of set.
Leo is also doing this type of thing with 13 mixes on a touring show called 'alex'

i have increased number of mixes in all versions for exactly this type of thing.
pro has 10 mixes - dv 8 - express 6 - lite 4...

you can change the mix keystone over dmx.

you need to work out method for yourself of doing thing type of thing - its all in the setup slides you create for yourself you need a grid with lots of crosses to hit the objects on the set.
to set marks for the mix keystone.

Thanks for the replies, good information in there!

I like the idea of having a mix per object, but I'm wondering... is it possible to reroute layers to different mixes via dmx? We have our entire show mapped out in layers, but those layers serve different functions over the course of the show.

Looking at the ground plans, we have 22 different setups for all those boxes.

We do have a pro server, so we have access to all the features. I'm on my way up to the theater now so I can play with it again. Thanks for the help!

Quote:

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Originally Posted by ljb2of3

Thanks for the replies, good information in there!

I like the idea of having a mix per object, but I'm wondering... is it possible to reroute layers to different mixes via dmx? We have our entire show mapped out in layers, but those layers serve different functions over the course of the show.

Looking at the ground plans, we have 22 different setups for all those boxes.

We do have a pro server, so we have access to all the features. I'm on my way up to the theater now so I can play with it again. Thanks for the help!

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yes it is possible to reroute the mix via dmx.

the enormous advantage of running the mix per object is that once its setup - you can run any movie or layer on the mix, shift its position, and scale it in and out- and its all perspectively correct.

Ok, so I figured out how to patch the mix layer select and mix shape... where can I find a DMX chart for those? The manual in catalyst only has the dmx charts for layers.

I've figured out how to assign mixes to outputs, so I've set it up so that three mixes are on the left screen and three are on the right screen. Thats where I need the most keystone control... I've left the center screen without any mixes besides mix 2 (output 2 runs all this) so I think I should be able to use run some layers there like normal.

Maybe I'll know when I see a dmx chart, but can I also change where mixes are assigned? I most likely can get along with only three mixes per side projector, but I'd like to know if it possible just in case they throw something even more crazy at me.

Thanks!

Ahh, found what I needed in the "whats new" document. I'm slowly getting closer to figuring things out!

Ok... back to having issues... if I could adjust the mix "Keystone Geometry" parameters via DMX, it would rock... I'm still playing with it, but so far, it looks like I still may not be able to do what I need with this since every scene is different.

If the set pieces were static I could set the scale and such as needed and leave it, but since the set pieces move all over creation, it may not work out for me this time.

Quote:

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Originally Posted by ljb2of3

Ok... back to having issues... if I could adjust the mix "Keystone Geometry" parameters via DMX, it would rock... I'm still playing with it, but so far, it looks like I still may not be able to do what I need with this since every scene is different.

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you can - its called mix shape.

which software version do you have?

m165 I believe

I was able to patch a "fixture" that lets me skew the corners of the keystone... but I have not found an option to adjust the mix's scale, aspect ratio, center x/y, and such via dmx...

Quote:

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Originally Posted by ljb2of3

m165 I believe

I was able to patch a "fixture" that lets me skew the corners of the keystone... but I have not found an option to adjust the mix's scale, aspect ratio, center x/y, and such via dmx...

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all you adjust are the keystone points.
everything else then comes from the layer position and scale.

I'm beginning to see a way to do this... looking over the ground plans, most scenes are right on with the projector, there are only two spots where it is important to keystone.

If I'm understanding correctly, I need to adjust the scale and aspect ratio of one mix to hit all the boxes in the view of the projector, then keystone to lay flat on them (lucky for me, they are all at the same angle on stage) Then, I can scale my layers as normal to fix the boxes.

It would be nice if I could adjust the other parameters of my shape via DMX... the options are there, but I can only set them via the GUI. But, it looks like what I need right now is possible.

Thanks!

Quote:

---

Originally Posted by ljb2of3

I'm beginning to see a way to do this... looking over the ground plans, most scenes are right on with the projector, there are only two spots where it is important to keystone.

If I'm understanding correctly, I need to adjust the scale and aspect ratio of one mix to hit all the boxes in the view of the projector, then keystone to lay flat on them (lucky for me, they are all at the same angle on stage) Then, I can scale my layers as normal to fix the boxes.

It would be nice if I could adjust the other parameters of my shape via DMX... the options are there, but I can only set them via the GUI. But, it looks like what I need right now is possible.

Thanks!

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you got to keep these things as simple as you possibly can with as few parameters as possible- otherwise you will get horribly confused - there are an infinite number of ways to do this ( or get it wrong )

Working with a single mix at a time:
1. Create a still image alignment file with a rectangle/grid with the same aspect ratio as the real world box you need to map onto
2. load this image onto a layer - and then a mix -and adjust the mix keystone points so that this still image file fits onto the real world object- at all corners-
there are an infinite number of scaling options to do this - just start with one.

3. repeat this for each object with a new alignment image.

do this one small step at a time - until you get more of a feel for how projective geometry works.

oh and make sure you have lots and lots of time - it cannot be done in a hurry.