Building an outdoor 'cinema' screen - Page 1
Forum section: electronics / general

author: Halcyon
author_rank: Unknown
timestamp: May 29, 2016, 01:43:08 am
content: I have quite a bit of bushland at the rear of my property and I thought It'd be nice to turn it into an outdoor cinema in the summer (or even winter, around a campfire).It need not be permenant, I figured some eye bolts in the trees to clip the screen in place when needed and some outdoor power outlets for the equipment. The screen itself, speakers and the projector can be brought out when required and packed away the rest of the time.I figured, since trees grow and move around, the screen would attach at each corner using rubber straps to allow for a taut viewing area but still has a bit of give in it.Has anyone done anything like this before? What sort of materials would be suitable for a projection screen? Ideally it should be something that can be rolled up and won't need ironing to get creases out.

author: tautech
author_rank: Super Contributor
timestamp: May 29, 2016, 01:54:55 am
content: Sounds like a fun project.Do you get much wind where you are as that might dictate the material you'll need to use.How big do you want it and will it be 16:9 or 4:3 ?I'm thinking one of the sunshade sail materials like they use at preschools, that's probably the toughest that comes to mind.For the bungees the rubber sealing rings that are used inside the collars of concrete pipes are pretty strong and often used for holding down truck tarps, they might br the go.

author: Ian.M
author_rank: Super Contributor
timestamp: May 29, 2016, 02:55:54 am
content: It will be very hard to avoid tension creases in a canvas or similar fabric screen tensioned entirely from the corners. You may well do better to have a scaffold pole frame guyed to the trees or pegs in the ground, with a good quality canvas sheet laced to it, and an off-the-shelf rollup projector screen hung from the top pole approx 4" in front of the canvas. The canvas would be a wind shield for the actual screen. Better yet, make a box frame with canvas sides and top so the wind cant get in at the edge of the screen so easily, and with the screen rolled up, it would be rain (but not storm) proof.If you *really* want to DIY the actual screen, I'd go to a canvas shop (marine, or auto trade) and ask them if they can either let you have some light coloured scraps to test projecting onto or lend you a sample book overnight. I suspect aluminised canvas would work quite well. However storing such a screen without creasing, or marking it or it getting mildew will be a royal PITA.

author: Halcyon
author_rank: Unknown
timestamp: May 29, 2016, 03:10:26 am
content: Quote from: tautech on May 29, 2016, 01:54:55 amWe can get windy days but more often than not, it's perfectly still or very light breeze. I'd be going 16:9, it wouldn't really matter if the screen was a bit bigger than the image.

author: LabSpokane
author_rank: Super Contributor
timestamp: May 29, 2016, 04:12:06 am
content: Inflatable screens are a thing now:http://www.target.com/p/airblown-inflatable-movie-screen-with-storage-bag-12-5/-/A-10866023?ref=tgt_adv_XS000000&AFID=google_pla_df&CPNG=PLA_Sports%2BShopping&adgroup=Inflatable+Projector+Screens_SC&LID=700000001170770pgs&network=g&device=t&location=9033784&gclid=CO6A59Sz_swCFQUFaQodLooKag&gclsrc=aw.ds

author: amspire
author_rank: Super Contributor
timestamp: May 29, 2016, 04:30:55 am
content: A cheap screen is white blockout curtain liner.Definitely will not be as bright as a reflective screen, but you can get it in pretty huge sizes. It is a white fabric often coated to block most of the sunlight. The coated liners can have a pretty good surface for use as a screen. Comes on rolls about 2.3 meters wide.The best way to make a screen is to build a wooden frame and stretch the liner over it.Here is an example:http://www.slendermorris.com/index.php/page/shop/flypage/product_id/1412/category_id/0a4f34b192632a05bc78926bc09093ba/offset/0?

author: Marco
author_rank: Super Contributor
timestamp: May 29, 2016, 06:17:41 am
content: Quote from: Ian.M on May 29, 2016, 02:55:54 amMight not be enough, but for the sunshade sails they stitch a strengthened band in concave sides. So when you pull hard on the corners you put force all along the sides trying to pull them straight, and the sail taught.

author: sony mavica
author_rank: Frequent Contributor
timestamp: May 29, 2016, 06:31:01 am
content: Quote from: amspire on May 29, 2016, 04:30:55 amthose things are not bad they use them at the park that is over the road from my house when the council puts on movies in the park once a year

author: Rick Law
author_rank: Super Contributor
timestamp: May 29, 2016, 07:57:25 pm
content: Quote from: Marco on May 29, 2016, 06:17:41 amRather than fight Physics, consider using a stiff horizontal "pole". Rather like theshower curtain rodwith the shower curtain - but fix mounted at closed-position instead of on rings to allow the curtain to open. With that stiff horizontal pole/rod,it will not have a center-sag. The rope's tension is just the weight of the screen+rod. You don't have to apply any additional force to stretch the screen as that is taken care of by the stiffness of the rod. Even better is to add a rod at the bottom as well keeping the bottom in equally firm shape.Depending on the weight of your screen (I am thinking 8 feet wide due to sizes of USA building supply material) .You need very thick PVC to avoid center-sag at 8 feet; but 1/8 thickness 1 inch diameter aluminum tube could be strong enough. The ends of the rod(s) ties to a rope with bungee-cord to the trees to give it some degree of freedom against the wind. If bungee-cord is not your choice, light (20-40lb) garage-door spring can work too.Best in my mind is wood! With wood, you can make an entire frame - taking center sagging or screen unevenness entirely out of the equation (of the tension needed to hang it). In the USA, we have the two-by-four wood which is 2inches x 4 inches x 8 feet (2x4 is at-cutting, pre polished). It is about 1.5" x3" x 8 feet (post trimmed) at the store. A couple of sizes down is even better. Around 1"x2"x8feet should be strong enough to hold the weight of a not-too-heavy screen. With a full wood frame, even just a staple every inch will stretch it nicely with each staple sharing just a small amount for force.Hey show us some pictures of your screen when you got it done!

author: JacobPilsen
author_rank: Regular Contributor
timestamp: May 29, 2016, 08:02:45 pm
content: Use white leatherette (imitation leather).For frame, Duraluminium alloy is best.

author: Marco
author_rank: Super Contributor
timestamp: May 29, 2016, 09:03:26 pm
content: Quote from: Rick Law on May 29, 2016, 07:57:25 pmWithout a full frame you kind of do. If you only tension the top and bottom with free sidesthisis what happens. Even with a top and bottom rod it still makes sense to have concave sides left and right with some non stretchy band stitched in. Then pulling on the bottom rod will apply sideways pressure across the entire screen. Easier to store and/or setup than a full frame tensioned screen.

author: Brumby
author_rank: Unknown
timestamp: May 30, 2016, 02:32:42 am
content: I did a free-standing outdoor screen about 25 years ago. It was a bolt-together setup with timber frame and white-painted plywood about 10' x 8'. It was a pain to wrangle and it needed to have some seriously heavy ballast to stop it from blowing around in the slightest breeze. Don't travel down this path unless you want to make it a permanent fixture.As for the anchors into the trees - you won't have to worry about the eye bolts moving. They will stay at the same height and position - the tree will just grow around them, eventually swallowing them up as it grows thicker.

author: ajb
author_rank: Super Contributor
timestamp: May 30, 2016, 04:04:31 pm
content: Tendo or spandex take projection very well, and being stretchy you don't have to worry about stretching out wrinkles. That said, with a straight-on projection and a straight-on viewing angle you won't really be much bothered by wrinkles, and a heavyweight muslin or canvas will be a good, inexpensive option as well.Look for a stage and studio supplier, they'll have a wide range of options, and you'll be able to get a number of fabrics in seamless widths far wider than what you'll find anywhere else. You'll also be able to order a piece sewn and finished to your specifications if you want to go the easy way. Spandex stretch shapes are commonly used in event decoration, so you might find something like that ready made that will work.In the US,Rose BrandoriWeisswould be the place to go. Googling for "stage and studio fabric Australia" produces some promising links that may be easier for you to deal with.

author: ez24
author_rank: Super Contributor
timestamp: May 30, 2016, 08:05:51 pm
content: Quote from: LabSpokane on May 29, 2016, 04:12:06 amDid not know about these before. Here is an Amazon link that has a lot of comments and questions. I think you might learn something from reading themhttp://www.amazon.com/Gemmy-39127-32-Outdoor-Inflatable-Widescreen/dp/B00DH5FS3Y/ref=sr_1_1?ie=UTF8&qid=1464638346&sr=8-1&keywords=Inflatable+Movie+ScreenInteresting that the fans run continuously