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ljb2of3
11-10-2008, 03:58 PM
I am unable to scale a layer with the keystone visual effect applied to it. In keystone setup I can scale it, but not when I switch back to the normal keystone mode.

This problem exists in 132 and 165

samsc
11-10-2008, 04:40 PM
I am unable to scale a layer with the keystone visual effect applied to it. In keystone setup I can scale it, but not when I switch back to the normal keystone mode.

This problem exists in 132 and 165

(And don't tell me to use keystoned submixes either... that simply isn't working for this show, I've tried)

what do you mean 'i am unable to scale a layer...'?

what do you mean this simply isnt working for this show?

- this is the way to do this - im in spain right now - doing a show with exactly this-

you need to figure out how to do this - it is imperative - its the only way to be able to scale and move layers on object.

did you need to follow the steps i indicated?
Did you create a test image with the correct aspect ratio for the stage object?

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Practise...

you then practise - set up a projector by yourself in a room- and practise setting up the mixes so that they align onto various points corners or objects in a room.
get a feel for how you set up the mixes to project onto different objects or surfaces in a room.
try different walls or cupboards etc.
watch how perspective projection works.
watch what happens when you move an object on a keystoned mix-
get out of the theatre - and into a private room.

practise moving a white blob from one corner to another- or up and down a wall.
Ask yourself :
"Did i setup the corner points correctly?"
"How accurate does this need to be?"
check and double check.

study...

You should also study the nature of perspective-
and perspective drawing:
http://www.khulsey.com/perspective_basics.html

watch how the size of windows on a building changes as it recedes into the distance?
windows with the same dimensions are the most useful - then you can see how they change shape?

imagine each one of those windows is a surface onto which you have to project an image?
see what happens?
what happens if you only have a single projector- can you see how the shape changes?

perpective and perspective mapping - and its inverses - are non-linear - every single point in the world has a unique perspective and a unique projection.

ljb2of3
11-10-2008, 06:01 PM
Sorry for being annoying here... I was rather frustrated earlier and shouldn't have posted while frustrated.

I'll go slowly and calmly this time.

My bug report... maybe its intentional, but it seems like a bug. Ignoring the submixes for a bit, when I attempt to keystone a layer by itself, I set the visual effect channel to keystone. When in that mode, adjusting the scale of the layer doesn't have any effect. Position, rotation, and aspect ratio work, scale doesn't at all.

Ok, back to the submix discussion. I will preface this with saying that for the shot I was working on, the projector is about 70 degrees off center, I will admit that it is a crazy shot, but its what I have to work with.

The LD and director decided to cut a couple of the less important extreme shots. Doing this allowed me to dedicate a submix to that one box, and by using the GUI controls, I was able to make it work.

Since I do not have DMX control of the scale or position of the keystoned submix, I was having to set the scale to 8 to get the image big enough to hit all the various positions that the box in question moved to. When the scale is set that high, moving the corners via DMX won't go far enough to do what I needed. Using the GUI controls it would. In this instance, having 16 bit control of the corners so I could go further would have done what I needed.

Using a submix per box is a great idea, and I'd love to do that. But, since the boxes turn and move all over the place, and I don't have full dmx control of the mix, I am forced to use a preset submix for only particular things, and go without a submix for other cues.

Having 16 bit control of all the paramters of a mix in keystone mode, rather than 8 bit control of only the corners, would have made my life much easier, and I wouldn't have been posting frustrated rantings earlier. :)

(The stress doesn't help either... being a full time student with another unrelated part time job doesn't leave much time to try and get this show up in the next 4 days... again, sorry for being annoying, try to bear with me)

samsc
11-10-2008, 06:15 PM
My bug report... maybe its intentional, but it seems like a bug. Ignoring the submixes for a bit, when I attempt to keystone a layer by itself, I set the visual effect channel to keystone. When in that mode, adjusting the scale of the layer doesn't have any effect. Position, rotation, and aspect ratio work, scale doesn't at all.

scale works for me - aspect ratio has no effect?

are you sure this isnt something else?
have you checked your channel assignments?

visfx5 keystone
visfx9 keystone setup.

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but you cannot scale an image with keystone points and have the projection stay perspectively correct-

if you use submixes- you can scale an image - and it stays perspectively correct.

to use the building example again- if you set up a keystone mix to 4 corners of the facade of a building - you can move a layer around in xy and scale - and at every point it is perspectively correct.
the windows will line up.

what a keystone does is describe a plane- and how points are mapped from 2d space to projective 3d.

samsc
11-10-2008, 06:39 PM
But, since the boxes turn and move all over the place, and I don't have full dmx control of the mix, I am forced to use a preset submix for only particular things, and go without a submix for other cues.

moving and turning boxes too?

with live video as they move and turn?

ljb2of3
11-10-2008, 07:42 PM
visfx5 keystone

Amazing how much reading the manual *AND* checking the fixture profile on the board would have avoided this whole discussion.

Turns out, the fixture profile was setting the channel to 006, not 005, when I pressed "keystone". Manually setting it to 005 makes everything work the way I thought it should. Now I can go back to programming things the way we had planned to months ago.

The reason I thought it was a bug was that I remembered doing it a long time ago... I thought I was going crazy!

I know how keystone works, the concept makes perfect sense. I'm using scale on the layer to get it close to the size of the box, then using keystone to put the corners of the image where I need them.


moving and turning boxes too?

with live video as they move and turn?

Not quite, that would make this much harder. The boxes move in the dark between scenes, but are in different places every scene. Content consists of mostly static images, with the occasional fire burning or glass breaking from time to time.

I've attached a couple of pictures I just took a few minutes ago. The colored lines all over the floor indicate the positions of the boxes.

All is happy here again... thanks for putting up with me and helping me figuring out what was going on.

samsc
11-10-2008, 09:07 PM
Amazing how much reading the manual *AND* checking the fixture profile on the board would have avoided this whole discussion.

Turns out, the fixture profile was setting the channel to 006, not 005, when I pressed "keystone". Manually setting it to 005 makes everything work the way I thought it should. Now I can go back to programming things the way we had planned to months ago.

cool. glad we sorted it out.

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its much harder to track objects moving in 3d! they dont move in straight lines in 2d->3d mapping. you need a lot of points/cues