Am I crazy?

Catherder

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Joined
Jun 2, 2019
Location
Portland OR
Do I have a good plan or am I just being ridiculous? For my club’s fall show I’m playing with the idea of building a translucent “mega-flat”. Ideally we’ll have a 12’ x 8’ piece. My plan is to use 3 sheets of coroplast attached to a frame of 1x3. The idea is to backlight it with cutouts of various scenery (houses for the village, twisty trees for the deep dark woods, etc) as silhouette backdrops so I would prefer to keep the cross bracing to a minimum, if not eliminate it all together. We do have a grid that I can attach it to, and I’m planning to brace the sides and weigh them down with sandbags.

My concerns at this point are that the overall structure will be too flimsy due to lack of bracing, and that we’ll have to push it too far downstage for decent illumination. I’ve tested on a small sheet with an led flashlight and it works pretty well, but my light guy is working festivals all summer and we won’t get onstage for another few weeks.

Any advice is welcome. Failure points, things I’m not thinking of. All that.
 

RonHebbard

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Premium Member
Joined
Jun 12, 2004
Location
Waterdown, ON, CA
Do I have a good plan or am I just being ridiculous? For my club’s fall show I’m playing with the idea of building a translucent “mega-flat”. Ideally we’ll have a 12’ x 8’ piece. My plan is to use 3 sheets of coroplast attached to a frame of 1x3. The idea is to backlight it with cutouts of various scenery (houses for the village, twisty trees for the deep dark woods, etc) as silhouette backdrops so I would prefer to keep the cross bracing to a minimum, if not eliminate it all together. We do have a grid that I can attach it to, and I’m planning to brace the sides and weigh them down with sandbags.

My concerns at this point are that the overall structure will be too flimsy due to lack of bracing, and that we’ll have to push it too far downstage for decent illumination. I’ve tested on a small sheet with an led flashlight and it works pretty well, but my light guy is working festivals all summer and we won’t get onstage for another few weeks.

Any advice is welcome. Failure points, things I’m not thinking of. All that.
@Catherder My initial thought(s)???
My initial thoughts: Beg, borrow, buy or rent a CPE "Fast-Fold" rear projection screen, complete with supporting legs and whichever masking skirts and legs you feel you require. CPE is / are one brand of several brands readily available. If you're not intimately familiar with assembling, erecting, anchoring, disassembling, folding and repacking such screens solicit the aid of one or two friends who ARE very familiar with such screens.
(Otherwise they can become an EXPENSIVE pile of trash in mere seconds if / when handled by the great unwashed and unknowing; no matter how well intentioned) [I purchased my first two 'Fast-Folds in 1973 and both are still serviceable other than one pair of legs which were lost AND NEVER REPLACED by a FORMER close friend.]
Unless you're using the screen outside on a windy day in BRIGHT sunlight, you shouldn't have any problems.
Keeping the projection surface smooth and taught will be neither a problem nor a concern.
Compare the cost of rental, delivery, set-up, disassembly and return AGAINST the cost of materials, construction, masking and removal of dust and debris.
I suspect renting a Fast-Fold screen will win hands down.
If you look around, you MAY find a supplier with a BLACK rear screen in stock; BLACK screens can be startlingly dramatic when a full color image appears on a pitch black screen; somewhat akin to a full color image magically materializing on the spiffy flat panel display on your desk.
'Fast-Folds' are manufactured in a range of stock and custom sizes from table top to at least 9' x 27' feet and that was back in the 1970's. With today's aspect ratios I'd suspect similarly large sizes are readily available along with supporting legs and masking drapes, typically black masking but some suppliers will have other colors in stock for weddings, funerals, and various corporate clients.
Models intended for rear screen applications will have ZERO cross bracing behind to interfere / shadow your images.
Who rents Fast-Folds in your area? I don't know, I'm up here north of Donald's walls; you're in Portland, Oregon; let's put Control Booth's 'Bat Call' to work and summon someone more local for you. I'll post this now and EDIT in someone local for you in a few minutes once I've found the right person for you.
EDIT: @Van Would you mind advising @Catherder from your closer perspective?
With all best wishes.
Toodleoo!
Ron Hebbard
 

Catherder

Member
Joined
Jun 2, 2019
Location
Portland OR

Who rents Fast-Folds in your area? I don't know, I'm up here north of Donald's walls; you're in Portland, Oregon; let's put Control Booth's 'Bat Call' to work and summon someone more local for you. I'll post this now and EDIT in someone local for you in a few minutes once I've found the right person for you.
EDIT: @Van Would you mind advising @Catherder from your closer perspective?
With all best wishes.
Toodleoo!
Ron Hebbard
Thanks @RonHebbard. I’m sure @Van has some thoughts on that one.
 

RonHebbard

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Jun 12, 2004
Location
Waterdown, ON, CA
Thanks @RonHebbard. I’m sure @Van has some thoughts on that one.
@Catherder Depending upon your time zone, you MAY need to give @Van a few hours to wake up.
You surprised me; a great many posters post a query then vanish into the ether never to be seen again. Thanks for your swift reply.
Toodleoo!
Ron Hebbard
 

derekleffew

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Las Vegas, NV, USA
... The idea is to backlight it with cutouts of various scenery (houses for the village, twisty trees for the deep dark woods, etc) as silhouette backdrops ...
Sounds like a job for a few ERSs and a few $12.95 gobos and call it a day. Front project onto any backdrop.



Around here the favorite manufacturer is Apollo Design, but I was too lazy to search their catalog and used whatever google images found as examples. Interesting that none of the results are of Apollo gobos. Maybe they're not spending enough on google payola?


While I don't hate the idea of using a fast-fold RP screen, note that they're pretty ugly unless something is always projected on them. When front lit, they're kind of a greenish-gray, and have the texture of sort of a very thick condom. The 8x24, 9x27, and 10x30' are good sizes for theatre use, but this format, known as "one over two" was intended for three banks (LCR) of 35mm Ektagraphic slide projectors and as such were obsoleted by the AV rental houses many years ago. Today's 4:3 and 16:9 aspect ratios aren't as stage friendly.
 
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RonHebbard

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Location
Waterdown, ON, CA
Sounds like a job for a few ERSs and a few $12.95 gobos and call it a day. Front project onto any backdrop.



Around here the favorite manufacturer is Apollo Design, but I was too lazy to search their catalog and used whatever google images found as examples. Interesting that none of the results are of Apollo gobos. Maybe they're not spending enough on google payola?


While I don't hate the idea of using a Fast-Fold RP screen, note that they're pretty ugly unless something is always projected on them. When front lit, they're kind of a greenish-gray, and have the texture of sort of a very thick condom. The 8x24, 9x27, and 10x30' are good sizes for theatre use, but this format, known as "one over two" was intended for three banks (LCR) of 35mm Ektagraphic slide projectors and as such were obsoleted by the AV rental houses many years ago. Today's 4:3 and 16:9 aspect ratios aren't as stage friendly.
@derekleffew and @Catherder Mr. Herder was speaking of an 8' x 12' size.
Understood about the "very thick condom" appearance.
I found it tolerable in most instances (as long as it didn't look like a used condom, used for any of several purposes and / or points of entryl)
Personally I much preferred Rosco's Black rear projection material (For a screen surface.) as long as the venue would work with the appreciably reduced lateral viewing angle. In several instances I draped a piece of seamless black scrim over my Fast-Folds to lessen the condom colored appearance.
Front projecting a gobo is a possibility as long as performers in front of the screen neither create a shadowing problem on the screen's surface nor are distracting when lit by the gobo from the patrons' perspective.
Front projecting a gobo, or any front projection, requires having a suitable location available to locate, power and control the projector, ellipsoidal, whatever the projection source. Of course if / when rear projecting you need to have sufficient stage depth available up stage of your screen to accommodate your projector of choice along with lenses suitable for your available throw distance and possibly additional depth to allow for performers (and or crew) crossing over from side to side during projection.
Toodleoo!
Ron Hebbard
 

Colin

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Joined
Jan 23, 2015
Location
Eastern Massachusetts
With wood construction this objective can be achieved rather well and rather affordably by building a frame "hog's trough" style. With 1x6 material I've done up to 12'x18'. Ideally, route a roundover on the inside edge of the face of the frame before stretching and stapling muslin or poly silk to it. The rules for crisp shadow projection are first to use a single point source and second to have the distance between the cutout and the screen be short in comparison to the distance from the light source to the cutout. Playing with that ratio and with the lighting angle can yield different looks, movement & scale illusions.
 

Catherder

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Joined
Jun 2, 2019
Location
Portland OR
Thanks for all the quick responses and ideas. Definitely some things to chew on.

Because they say a picture is worth a thousand words here is the look I’m going for - with the acknowledgment that this is from a national ballet production and we are but a humble volunteer club working with kids ;). In other words, installing digitally printed full size backdrops that can fly in and out depending on the scene is right out.

Edit: also I don’t expect to replicate this drop either. Illustrative purposes only

C1899F2B-6B7A-45C7-BBA7-F34ACB2AED0E.jpeg
 
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kicknargel

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Joined
Aug 10, 2009
Location
Denver, CO
In general I think your idea is good. Coroplast backlights really well, and you could uplight it with any kind of cyc lights with just a few feet of stage depth. To avoid the seams, you could build a frame and use any number of fabrics (some mentioned above). Poly muslin / poly cyc is good for backlighting, or spandex, or rear projection material. Many people also use shower curtains.

Wait, are you putting the cutouts in front or behind the "cyc?" I'd suggest you'd get better results with them in front, so they can show black in front of color, rather than look like unlit coroplast surrounded by lit coroplast. But maybe you want them hidden for scene change purposes.

Another nice touch is to put a black scrim DS of the whole rig. That way when unlit it goes to black rather than dingy white. (Similar to the black RP screen Ron suggests.)
 

Catherder

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Jun 2, 2019
Location
Portland OR
@kicknargel - the original idea was to put them behind for a couple of reasons. Easier construction, and scene changes. But the more feedback I get and the more I play with designs the less I like it. Eh - when was the first idea ever the last idea? I think, really, what I need to do is convince the other club members to bite the bullet and buy a cyc instead of half assing something for almost as much money.
 

Van

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PjB

Member
Joined
Nov 12, 2015
Location
NH
Do I have a good plan or am I just being ridiculous? For my club’s fall show I’m playing with the idea of building a translucent “mega-flat”. Ideally we’ll have a 12’ x 8’ piece. My plan is to use 3 sheets of coroplast attached to a frame of 1x3. The idea is to backlight it with cutouts of various scenery (houses for the village, twisty trees for the deep dark woods, etc) as silhouette backdrops so I would prefer to keep the cross bracing to a minimum, if not eliminate it all together. We do have a grid that I can attach it to, and I’m planning to brace the sides and weigh them down with sandbags.

My concerns at this point are that the overall structure will be too flimsy due to lack of bracing, and that we’ll have to push it too far downstage for decent illumination. I’ve tested on a small sheet with an led flashlight and it works pretty well, but my light guy is working festivals all summer and we won’t get onstage for another few weeks.

Any advice is welcome. Failure points, things I’m not thinking of. All that.
I don't often get the chance to help out here, so I'm happy to finally be in a position to contribute from a shadow artist's perspective. The type of light source and distance behind the screen are going to be key variables. A single, small LED gives the best range of distance from light source to screen, allowing you to utilize smaller silhouettes and "grow" them by putting them closer to your light source and further from the screen. Of course small LEDs won't compete well with stage lights nor likely fill your screen. Larger LEDs will blur the shadow image as the silhouette gets close to the light. Any unfocused lamp with a long filament will give you blurred images. Multiple light sources will give you multiple images as we'll as opportunities for special effects by controlling the overlap of light. If you'd like to keep your silhouettes small and get a large shadow, the best solution is a single halogen lamp. The idea is to use a single, point source (small filament) lamp. Halogens run hot, so safety will need to be considered. Otherwise, your silhouettes will need to be close in size to what you want the shadow to be, and they'll need to reside close to the screen.
 

josh88

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The type of light source and distance behind the screen are going to be key variables. A single, small LED gives the best range of distance from light source to screen,
I agree with the first half, the second have I don't know that I agree with. I agree with a single fixture, but I've had issues with led's with multiple sources IN that fixture (light bright led fixtures like single color LED pars) Multi colored led's I've had less problems with, but have still had weird fringing if its a par with Multiple LED's. So an ERS gives you more versatility and a single source of light. There are a lot of factors, but the two ways I like to do it are a single high angle ERS which allows you room to maneuver and line up new puppets/scenery in the void under that light and then push them forward towards the "screen".

OR I like something like an RP overhead projector set up. Where the light source is bounced onto the screen with a mirror so that you're able to have 2 planes of shadow. On a simple small scale I have actually used an over head. It lets you set scenery pieces on the table that get projected large and then for depth you can build other pieces (or have puppets or whatever moveable pieces) to stage behind the screen at whatever point you'd like for size/sharpness. If you were actually doing puppetry and not scenery I'd recommend a par on a boom between the operate and the puppets, it most closely mimics the open flame origins of certain cultures, but all of that is another story.
 

Catherder

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Jun 2, 2019
Location
Portland OR
@PjB and @josh88 - Thanks for the feedback. I just don’t think I have the space upstage to get a decent amount of light coverage on the screen from a single source. I’ve got maybe 4’ tops. Our stage is TINY. I was thinking more of cutouts directly behind it and some led strips angled up from the floor. It’s a fairy tale so it’s fitting the feel if the shadows are ephemeral and “misty”.

Still noodling away.
 

josh88

Remarkably Tired.
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Location
Ypsilanti, Michigan
A S4 with a 90 degree barrel makes a 7 1/2' pool at 4 feet. A S4 Par with a WFL lens and the bottle spun right would probably fill a 12x8 screen pretty well. Especially with some diffusion gel in it.

Take the inventory you have and schedule a play day. Try different fixtures, different angles, single/multiple fixtures, different locations and just see what results you get and if any are what you're looking for. Even if it just casting your shadows on a wall with the distance measured out to match your space.
 

Colin

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Jan 23, 2015
Location
Eastern Massachusetts
@PjB and @josh88 - Thanks for the feedback. I just don’t think I have the space upstage to get a decent amount of light coverage on the screen from a single source. I’ve got maybe 4’ tops. Our stage is TINY. I was thinking more of cutouts directly behind it and some led strips angled up from the floor. It’s a fairy tale so it’s fitting the feel if the shadows are ephemeral and “misty”.

Still noodling away.
Find yourself a Linnebach projector!
 

Catherder

Member
Joined
Jun 2, 2019
Location
Portland OR
Ok Booth - what is this? Painted drop, cutouts in front and uplit from behind them, cutouts behind the drop and lit from behind, something else? This backdrop is the look I want. I also legitimately don’t know :(

Thanks again for all the input.

27D7B389-5993-4EDF-A977-3DB962FE7E17.png
 

RonHebbard

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Location
Waterdown, ON, CA
Ok Booth - what is this? Painted drop, cutouts in front and uplit from behind them, cutouts behind the drop and lit from behind, something else? This backdrop is the look I want. I also legitimately don’t know :(

Thanks again for all the input.

View attachment 18362
@Catherder O.K., since no one else is playing, I'll play the game.
My guess is: A rear lit cyc' or RP screen with a matte black cut-out either unlit in front OR behind. I also suspect they're lighting the drop from the floor behind and they've more than four feet of space.
Toodleoo!
Ron Hebbard