My Parkland Plastics Portable Screen  

Hello everyone! For my first thread, after spending a couple months just reading and reading and absorbing and reading some more, I figured I should contribute to the forum by sharing the particular screen design I came up with. Who knows, maybe there's someone out there who might like this approach and find it useful?

My story is pretty common, I suppose. Always wanted a front projector... I recently bought a refurbished X1 and a Zenith 318, and along with a Cinemascope (actually, a French made Hypergonar) 2x projection lens I acquired a few years back, I've got a pretty decent (and low cost) near-HD image to project (or "enhanced definition", anyways). But I needed a screen... and preferably, a temporary and portable one that I could construct in my living room, break down on occasion, and take over to my friends' places and reconstruct in just a few minutes.

I was going to buy a $600 Da-lite Fast-fold portable screen, which I was familiar with, having rented it... but it would have cost as much as my projector and there would've been no dress kit included. But, as the trite expression goes, "necessity is the mother of invention"... and thanks to the minds gathered at this forum and a little ingenuity on my part, I think I've come up with a perfectly acceptable, low cost solution. So here goes...


Materials List:

(1) 60" x 60" Projection Screen w / tripod stand
(1) 8' x 4' Parkland Plastics sheet
(2) 4' lengths of 1" x 1/8" right angle aluminum
(2) 50" lengths of 1" x 1/8" right angle aluminum
(2) 48-1/2" lengths of 1/4" diameter threaded rod
(1) 1/4" coupling nut
(4) 1/4" nuts
(2) 6-32 self-tightening nuts
(1) 1" hinge
(6) 6-32 screws cut to various lengths
(3) #6, 1/2" sheet metal screws with 1/4" hex heads and drill points
(2) Heavy duty picture frame hooks
(1) Flat brass hook
(2) Boxes of 15’ sticky back 3/4" Velcro
(2) 28†– 48†extension type curtain rods
(1) Pair of 82†wide x 72†long black tab top curtains
(4) 51†lengths of 3-1/2†black fabric vertical blind material
(1) 10’ x 3’ heavy black Duvateen
(1) 1/4" aluminum screw (8-32 thread) & post (3/16†diameter)
(1) 8-1/2’ of 12 gauge black copper wire
(2) 1-1/4†wide binder clips
(2) 3/4" wide binder clips


Tools:

Drill & metal drill bits
5/16†& 1/4†nut drivers
Flat head screwdriver
Hacksaw with metal blade
Tap and Die set
Heavy duty hand tacker/staple gun with staples
Standard office stapler
High temp. glue gun & glue sticks
Roll of black electrical tape

***

Unfortunately, I did not document the actual fabricating process, but these pictures showing
how to put the portable screen together should give you enough to go by or to add your own
ideas to the overall design. Here we see all the various parts packed up and ready to be
either constructed or transported away.



http://home.earthlink.net/~particlew...-and-Parts.jpg

From the top down you can see the store bought projection screen, the hinged bottom aluminum
frame, the left and right side pieces, the threaded rods, and the 12 gauge wire that I use to
stretch the top of the screen taut and straight. (In the future I may substitute the wire with a
steel cable and turnbuckle for added strength and stability.)

The lower panel is a close-up of the various nuts and screws and the two heavy-duty picture
frame hooks that I contorted and rearranged in a vice to hold my curtain rods.



http://home.earthlink.net/~particlew...ame-Pieces.jpg

On the left panel is a better view of the hinged bottom aluminum frame. Notice how I’ve placed
the squares and rectangles of Velcro… those are used to hold the pleated Duvateen “skirtâ€
that I’ve made to frame the bottom of the screen down to the floor and hide the tripod legs. You
can just make out the long strips of Velcro on the adjacent sides that are used to hold the bottom
of the Parkland screen in place. Also, notice the two screws that will hold the side pieces.

In the middle panel are the left and right sides of the frame… you can’t see the Velcro on either,
but face down on both is a strip that runs nearly the entire length of the pieces.

On the right panel you can see the threaded rods with the coupler on one.



http://home.earthlink.net/~particlew...inge-Clasp.jpg

Here is a close-up of the hinge on the bottom frame. The hook isn’t very sturdy, but it doesn’t
really have to be.



http://home.earthlink.net/~particlew...ide-Pieces.jpg

These are the tops of the left and right side pieces. Notice I’ve drilled several holes and
notched out a gap with my hacksaw.



http://home.earthlink.net/~particlew...nd-Coupler.jpg

This is rather self explanatory… just joining the two threaded rods.



http://home.earthlink.net/~particlew...ing-Thread.jpg

1.) Set up the tripod projection screen.
2.) Adjust the bottom of the screen to a preset mark and lock it in place.
3.) Stretch the screen up a few feet and secure it (notice the Velcro along the top of the screen).
4.) Take the plastic end caps off (note the hole I drilled).
5.) Slide the joined threaded rods through the top of the screen.
6.) Slide the right end cap back on and align with a preset mark.
7.) Pull the rod through on the left and slide the end cap on.
8.) Align the left side of the rod with another mark.
9.) Extend the screen up so that the screen is 4 feet high.



http://home.earthlink.net/~particlew...ttom-Frame.jpg

Place the bottom frame on top of the projection screen’s spring loaded housing. Remove the two
top existing screws that hold the plastic end caps on the housing and replace them with your
self drilling sheet metal screws. Previously, I had drilled with a self drilling screw near the center
of the spring loaded housing so I could later secure it as well. Be careful not to drill into the screen
material.



http://home.earthlink.net/~particlew...ring-Sides.jpg

The left and right side pieces are held in place with the screws protruding from either side of
the bottom frame and secured with the self-tightening nuts.



http://home.earthlink.net/~particlew...rtain-Rods.jpg

1.) Place the heavy duty picture frame hooks on the top of either side piece.
2.) Get your curtain rods.*
3.) Slide the right curtain rod onto the right-side threaded rod.
4.) Put one nut on the end of the threaded rod about half an inch back.
5.) Secure the rod with another nut
6.) Place the curtain rod into the picture frame hook.
7.) This is the finished appearance.
8.) Do the same for the left side.
9.) Extend the 12 gauge wire across from either side for further stability.

* Notice I’ve placed some Velcro around both curtain rods and put zip ties on either side to
hold them in place. The Velcro is there to secure the top masking for 1.85 and 1.33 projection.
To make the curtain rods black, I’ve simply wrapped them in electrical tape. Initially I just
drilled holes in the curtain rods so I could slide them onto the threaded rods… but later I took a
hacksaw to the curtain rods and notched out a path to the hole so I didn’t have to take the nuts
off the running thread and remove the wire just to get the curtain rods on or off.



http://home.earthlink.net/~particlew...-and-Skirt.jpg

1.) Get your rolled-up Parkland Plastics screen (notice the Velcro around the back edge of the screen).
2.) Put the screen on the newly built frame (I use a center mark on the screen and frame to guide me).
3.) Take your pleated “skirtâ€.*
4.) Velcro it to the small ledge on the bottom frame.
5.) Here’s how it should look.
6.) Take your top and bottom masking (the vertical blind material).
7.) Stretch it across the bottom of the screen and secure it with the Velcro.
8.) This gives a nice, straight bottom frame.
9.) Do the same for the top and use a 3/4" wide binder clip to hold it to the screen at the
center.

* Use heavy-duty staples along with regular staples and hot glue as needed to pleat the Duvateen
and secure the Velcro.


***


Next up are the final pictures...

http://home.earthlink.net/~particlew...t-Curtains.jpg

Here is the 2.35:1 setup sans curtains. There should be 96†x 41†of the screen showing, or
about 105†diagonal. There should also be near-perfect right angles. My camera lens’ wide focal
length has distorted the screen slightly here.



http://home.earthlink.net/~particlew...reen/Scope.jpg

2.35:1 with the curtains. I have folded over and stapled the tab top loops on the curtains so the
curtains themselves don’t hang down so far.



http://home.earthlink.net/~particlew...creen/Flat.jpg

1.85:1. There should be about 85†x 46†showing, or about 97†diagonal. For me that’s two
curtain loops in from the curtain rod hook on either side. Notice the top masking is now held in
place by the Velcro I put on the curtain rods. I use a 1-1/4†binder clip to hold the strip in the
center. One of the binder clip’s silver handles is left in place to fit around the original projection
screen’s downward facing hook. I can provide a picture if that’s too confusing.



http://home.earthlink.net/~particlew...en/Academy.jpg

1.33:1. There should be about 61†x 46†showing, or about 76†diagonal. The curtain loops
are all on the screen side of the curtain rod hooks.


***


Well, that's about it. If anyone is interested and has questions about certain details or wants clarification on some things, don't be afraid to ask.

Thanks! I'm glad you liked it. As for the lens, the short throw range is partly why I use it. I'm about ten feet back from the screen at either 1.33:1 or 2.35:1. With my Zenith 318 set at 1080i, I use its vertical zoom to stretch the 2.35:1 image to 1.78:1... then I have the X1 set in 4:3 mode which compresses that 16x9 image horizontally. There is some pixel cropping on the Zenith, so the X1 displays about a 1.30:1 image.

As you can see in the picture below, I've taken the Anamorphic lens apart, cut the barrel down and brought the elements a bit closer together to cut down on vignetting (in this setup, its a very, very slight darkening of the image at the bottom corners, which I would have to point out to people for them to see it). I've also removed the plastic zoom and focus rings on the X1, to bring the Anamorphic closer to the projector's actual lens. By futzing around with the Anamorphic and having a short throw distance, my actual horizontal stretch is about 1.9x instead of 2x.

I've also turned the "tracking" down to zero in the X1's menu which compresses the image horizontally a bit further. I figure I'm getting between 2.44:1 - 2.47:1 on modern scope DVDs. The right and left sides of the image spills onto my curtains about 3 to 4 inches on either side. It's probably only about a 3% to 7% additional horizontal stretch. To my eyes, I can't perceive a difference.

The focus is good, the brightness is good, there's no objectionable color separation. There is a slight pincushioning effect from the anamorphic, but with the masking it's beyond the screen and only noticeable on straight horizontal lines near the bottom 4th of the screen.

I'll post an image later tonight of a 2.35:1 movie.

http://home.earthlink.net/~particlew...ector-lens.jpg

Thanks! That's very nice of you to say. I was hoping I came across clearly enough... sounds like I did.


Then again... :D


Thank you.

For 2.35:1, yes... I'm just masking on the top and bottom. But to tell you the truth, I'm not really doing the Constant Area concept justice, because I have a 2:1 screen underneath all that masking. For true Constant Area -- if that is what you are striving for -- you need a 1.78:1 screen (16x9).

http://home.earthlink.net/~particlew...stant-Area.jpg

This is true constant area, as I understand it.



http://home.earthlink.net/~particlew...stant-Area.jpg

This is what I'm getting. My 1.33:1 could in principle be a little bigger (and so could my 1.85:1 for
that matter), but in practice, I can't easily get my bottom masking down far enough because
of the material I'm using (the vertical blind material) and that little aluminum ledge on the bottom
frame piece.